In the crystal, molecules are associated into inversion dimers via short Cl⋯Cl contacts [3.3763 (9) Å]. A Hirshfeld surface analysis indicates that the most important contact percentages for the different types of interactions are H⋯H (43.9%), Cl⋯H/H⋯Cl (22.9%), C⋯H/H⋯C (20.8%) and N⋯H/H⋯N (8.0%).In the title compound, C In order to continue our work in this direction, we now describe the synthesis and structure of the title compound, CDatabase survey.The title compound has a non-planar molecular conformation Fig. 1; the dihvia short halogen⋯halogen contacts  compared to the van der Waals radius sum of 3.50 Å. No other directional contacts could be identified and the shortest aromatic-ring-centroid separation is greater than 5.25 Å. The packing for (I)In the crystal, molecules of (I)et al., 2007CrystalExplorer17 The Hirshfeld surface (McKinnon a) and those delineated into H⋯H, Cl⋯H/H⋯Cl and C⋯H/H⋯C contacts . The pair of characteristic wings in the fingerprint plot delineated into C⋯H/H⋯C contacts , have the tips at de + di ≃ 2.80 Å. The remaining contributions from the other different interatomic contacts to the Hirshfeld surfaces are listed in Table 1et al., 2015The overall two-dimensional fingerprint plot Fig. 4a and thce Fig. 4c. The pet al., 2016E)-1--2-phenyldiazene unit resulted in 25 hits. Six compounds are closely related to the title compound, viz. 1-(4-bromophenyl)-2-diazene , C—H⋯Cl and C—Cl⋯π interactions into sheets parallel to the ab plane. Additional van der Waals interactions consolidate the three-dimensional packing. In the crystal of HODQAV, the planes of the benzene rings make a dihedral angle of 56.13 (13)°. Molecules are stacked in columns along the a-axis direction via weak C—H⋯Cl hydrogen bonds and face-to-face π–π stacking interactions. The crystal packing is further consolidated by short Cl⋯Cl contacts. In XIZREG, the benzene rings form a dihedral angle of 63.29 (8)°. Molecules are linked by C—H⋯O hydrogen bonds into zigzag chains running along the c-axis direction. The crystal packing also features C—Cl⋯π, C—F⋯π and N—O⋯π interactions. In the crystals of LEQXIR and LEQXOX, the dihedral angles between the aromatic rings are 56.18 (12) and 60.31 (14)°, respectively. In LEQXIR, C—H⋯N and C—H⋯O hydrogen bonds and short Cl⋯O contacts occur and in LEQXOX C—H⋯N and short Cl⋯Cl contacts are observed.In the crystals of HONBOE and HONBUK, the aromatic rings form dihedral angles of 60.9 (2) and 64.1 (2)°, respectively. Molecules are linked through weak Z)-4-{[2-hydrazineylidene]methyl}-N,N-dimethylaniline , tetramethylethylenediamine (TMEDA) , CuCl  and CCl4 . After 1–3 h  the reaction mixture was poured into ∼0.01 M solution of HCl  and extracted with dichloromethane (3 × 20 ml). The combined organic phase was washed with water (3 × 50 ml), brine (30 ml), dried over anhydrous Na2SO4 and concentrated in vacuo using a rotary evaporator. The residue was purified by column chromatography on silica gel using appropriate mixtures of hexane and dichloromethane (3:1–1:1) to form a red solid in 85% yield (m.p. 429 K). Orange plates of (I)18H19Cl2N3: C 62.08, H 5.50, N 12.07; found: C 62.01, H 5.48, N 12.03%. 1H NMR  δ 2.38 , 3.05 , 6.88–7.43 . 13C NMR  δ 155.57, 153.15, 151.94, 147.03, 142.69, 138.64, 137.97, 133.14, 131.20, 127.08, 121.02, 21.20. ESI–MS: m/z: 349.18 [M+H]+.A 20 ml screw-neck vial was charged with DMSO (10 ml), (Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C) was applied in all cases.Crystal data, data collection and structure refinement details are summarized in Table 210.1107/S2056989020009202/hb7912sup1.cifCrystal structure: contains datablock(s) I. DOI: 10.1107/S2056989020009202/hb7912Isup2.hklStructure factors: contains datablock(s) I. DOI: 2014419CCDC reference:  crystallographic information; 3D view; checkCIF reportAdditional supporting information:


The phenol ring makes a dihedral angle of 36.56 (3)° with the nitrobenzene ring. In the crystal, molecules are linked by C—H⋯O interactions, forming chains along the  15H14N2O3, was prepared by condensation of 2-hydroxy-5-methyl-benzaldehyde and 2-methyl-3-nitro-phenylamine in ethanol. The configuration of the C=N bond is E. An intramolecular O—H⋯N hydrogen bond is present, forming an S(6) ring motif and inducing the phenol ring and the Schiff base to be nearly coplanar [C—C—N—C torsion angle of 178.53 (13)°]. In the crystal, molecules are linked by C—H⋯O interactions, forming chains along the b-axis direction. The Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (37.2%), C⋯H (30.7%) and O⋯H (24.9%) interactions. The gas phase density functional theory (DFT) optimized structure at the B3LYP/ 6–311 G level is compared to the experimentally determined molecular structure in the solid state. The HOMO–LUMO behaviour was elucidated to determine the energy gap.The title compound, C Depending on the tautomers, two types of intramolecular hydrogen bonds are generally observed in ortho-hydroxy Schiff bases, namely, O—H⋯N in enol–imine and N—H⋯O in keto–amine tautomers  ring motif and also induces the phenol ring and the Schiff base to be nearly coplanar, as indicated by the C3—C8—N1—C9 torsion angle of 178.53 (13)°. An intramolecular C15—H15B⋯O2 interaction is also observed. The phenol ring (C1–C8/O1) is inclined to the tolyl ring (C9–C14) by 37.57 (3)°, and the nitro group (N2/O2/O3) is inclined to the tolyl ring (C9—C14) by 35.05 (2)°. The configuration of the C8=N1 bond is E. The C4—O1 distance is 1.3455 (18) Å, which is close to normal values reported for single C—O bonds in phenols and salicylideneamines i and C7—H7C⋯O1i, resulting in the formation of an infinite chain along the b-axis direction . The two-dimensional fingerprint plots  provide information about the percentage contributions of the various interatomic contacts. The most important are H⋯H interactions, which contribute 37.2% to the total Hirshfeld surface. Other contributions are from C⋯H (30.7%), O⋯H (24.9%), N⋯H (2.0%) and C⋯O (1.8%) contacts. There are also smaller contributions  using the standard B3LYP functional and 6-311G basis-set calculations , the ionization potential (I = −ELUMO), HOMO–LUMO energy gap (ΔE), the chemical hardness (η) and softness (S) of the title compound were predicted based on the EHOMO and ELUMO energies. As a result of the large ΔE and η values (Table 3E)-2-{[(3-chlorophenyl)imino]methyl}-6-methylphenol -2-[(2-hydroxy-5-methoxybenzylidene)amino]benzonitrile -4-methyl-2-[(2-methyl-3-nitro-phenylimino)methyl]phenol moiety resulted in no hits when both methyl groups were included in the search. Without the methyl groups, seven related compounds were found. Out of these, few are very similar to the title compound and some are metal complexes such as diazido-}bis(4-methylphenolato)]manganese amino]-4,5-dinitrophenyl}imino)methyl]-4,6-di-t-butylphenolato}iron(III) methanol solvate hemihydrate amino]-4,5-dinitrophenyl}imino)methyl]phenolato}iron(III) bis]nickel(II) methanol solvate -4,5-dinitrophenyl]azanediyl}bis(methylene)]bis}methanolcobalt(III) methanol solvate -3-nitroaniline  in ethanol (15 ml) and 2-methyl-3-nitro-phenylamine  in ethanol (15 ml). The reaction mixture was stirred for 5 h under reflux. Single crystals of the title compound suitable for X-ray analysis were obtained by slow evaporation of an ethanol solution .Uiso(H) = 1.5Ueq(O). Other H atoms were fixed geometrically and treated as riding with C—H = 0.96 Å (methyl) or 0.93 Å (aromatic), Uiso(H) = 1.2Ueq(C) or 1.5Ueq(Cmethyl).Crystal data, data collection and structure refinement details are summarized in Table 410.1107/S2056989020011652/zl2794sup1.cifCrystal structure: contains datablock(s) I. DOI: 10.1107/S2056989020011652/zl2794Isup2.hklStructure factors: contains datablock(s) I. DOI: Click here for additional data file.10.1107/S2056989020011652/zl2794Isup3.cmlSupporting information file. DOI: 2025323CCDC reference:  crystallographic information; 3D view; checkCIF reportAdditional supporting information:


CENP‐A‐containing nucleosomes. To preserve centromere identity, CENP‐A must be escorted to centromeres by a CENP‐A‐specific chaperone for deposition. Despite this essential requirement, many eukaryotes differ in the composition of players involved in centromere maintenance, highlighting the plasticity of this process. In humans, CENP‐A recognition and centromere targeting are achieved by HJURP and the Mis18 complex, respectively. Using X‐ray crystallography, we here show how Drosophila CAL1, an evolutionarily distinct CENP‐A histone chaperone, binds both CENP‐A and the centromere receptor CENP‐C without the requirement for the Mis18 complex. While an N‐terminal CAL1 fragment wraps around CENP‐A/H4 through multiple physical contacts, a C‐terminal CAL1 fragment directly binds a CENP‐C cupin domain dimer. Although divergent at the primary structure level, CAL1 thus binds CENP‐A/H4 using evolutionarily conserved and adaptive structural principles. The CAL1 binding site on CENP‐C is strategically positioned near the cupin dimerisation interface, restricting binding to just one CAL1 molecule per CENP‐C dimer. Overall, by demonstrating how CAL1 binds CENP‐A/H4 and CENP‐C, we provide key insights into the minimalistic principles underlying centromere maintenance.Centromeres are microtubule attachment sites on chromosomes defined by the enrichment of histone variant  CAL1 binds both pre‐nucleosomal CENP‐A/H4 histone dimers and the centromere receptor CENP‐C, thus combining the activities of mammalian counterparts HJURP and Mis18 complex.X‐ray crystallography reveals how the evolutionary distinct histone chaperone  Centromeres are specialised chromosomal regions that act as a platform for the assembly of kinetochores, the microtubule anchoring sites essential for chromosome segregation during mitosis and meiosis , but lack clear homologues of HJURP and the subunits of the Mis18 complex. Instead, fly‐specific CAL1 appears to combine the roles of both HJURP and the Mis18 complex: pre‐nucleosomal CENP‐A recognition and its targeting to the centromere for deposition, respectively   is sufficient to interact with CAL1 and H4. Subsequently, using CAL11–160, CENP‐A144–255 and H4, we reconstituted a truncated protein complex (His‐CAL11–160–CENP‐A144–225–H4). The molecular weights (MW) measured for His‐CAL11–160–CENP‐A101–225–H4 and His‐CAL11–160–CENP‐A144–225–H4 using size‐exclusion chromatography combined multi‐angle light scattering (SEC‐MALS) are 47.0 ± 0.9 and 43.4 ± 0.8 kDa, respectively  residues 1–200 predicted to fold into α helices Fig A and B. vely Fig C. These 1–160–CENP‐A101–225–H4 and CAL11–160–CENP‐A144–225–H4 yielded two different crystal forms: form I that diffracted X‐rays to about 3.5 Å and form II that diffracted anisotropically to about 4.4 Å (Table Drosophila melanogaster (dm) H3/H4 heterodimer  . Purified recombinant CAL11–160–CENP‐A101–225–H4 complex was cross‐linked using EDC (solid lines), a zero‐length cross‐linker that covalently links carboxylate groups of Asp or Glu residues with primary amines of Lys and N‐terminus, or hydroxyl group of Ser, Thr and Tyr, or BS3 (dashed lines), a cross‐linker that covalently links amine to amine or hydroxyl group of Ser, Thr and Tyr. The cross‐linked peptides were analysed by mass spectrometry to identify intra‐ and intermolecular contacts  is very similar to human CENP‐A/H4 (PDB: 3NQJ)  and hydrophobic (involving CAL1 L11 and M14) interactions, the C‐terminal half, mainly aa W22 and F29, is sandwiched between CENP‐A α2 and H4 α3    and without α helical elements (CAL11–50) to bind CENP‐A/H4 did not show a noticeable difference under the conditions (buffer containing at least 1M NaCl) needed for CENP‐A/H4 solubility. We speculate that in a cellular context post‐translational regulation such as phosphorylation or/and other intermolecular interaction involving the downstream helical segments of CAL1 might modulate CENP‐A/H4 binding dynamics required for correct CENP‐A recruitment at centromeres. This may be a possible explanation for why CAL11–50 is not sufficient for CENP‐A recruitment in cells  and tested their ability to interact with His‐CAL11–160 in a nickel‐NTA pull‐down assay    and a four‐stranded (β4‐β9‐β6‐β7)  and analysed their oligomeric structure by measuring the MW using SEC‐MALS  , the overall fold conferring the β barrel structure is conserved. However, two loop regions  show striking conformational variation as compared with their equivalent regions in budding yeast CENP‐C, Mif2p . The structure reported here and PDB: 6O2K are nearly identical and superpose well with an RMSD of 0.27 Å  . Next, samples comprising a SEC purified untagged complex were analysed. Both the mass and sedimentation coefficient are consistent with a 2:1 complex, but not with a 2:2 complex . Thus, the AUC together with the crystal structure shows that CENP‐C cupin dimer binds just one copy of CAL1 at any given time.Although CAL1 binding by CENP‐C involves just a cupin monomer, only one of the two cupin monomers was observed to interact with CAL1, while the equivalent CAL1 binding site of the dimeric counterpart was empty in the crystal structure. We speculate that the other binding site might be sterically hindered by the remaining residues of CAL1 not seen in the crystal structure, thus not allowing a second monomer of CAL1 to bind. This agrees with our previous observation that CAL1AUC) Fig C demonst101–225 and H4 in a similar manner to CAL11–160. The resulting folded complex was analysed by SEC on its own and mixed with 1.2 molar excess of His‐CENP‐C1264–1411  compared to His‐CAL11–160‐LL‐841–979/CENP‐A101–225/H4 (14.62 ml) and His‐CENP‐C1264–1411 (16.05 ml) on their own  results in genome instability, often leading to cell death. To maintain centromere identity defined by the enrichment of CENP‐A containing nucleosome, the CENP‐A‐specific chaperone (HJURP in humans and Scm3 in yeast) escorts CENP‐A until its incorporation into the centromeric chromatin  and Schizosaccharomyces pombe (Cnp3) CENP‐C cupin domains, with striking differences in the mode of dimerisation  and used directly in ligation‐independent cloning (LIC) into bacterial expression vectors. Smaller fragments were amplified using PCR and then used for LIC. CAL11–160‐LL‐841–979 was produced using homologous PCR.Codon optimised All mammalian expression vectors used in this study were constructed in a pN2‐CMV vector.101–225 was generated in  Gold (Agilent) grown in 2XTY media. His‐CENP‐C1264–1411 was expressed in Rosetta (DE3) (Novagen) cells, using 2XTY. His‐SUMO‐CAL1841–979 was expressed in BL21 (DE3) Gold in LB. After reaching O.D ~ 0.6 at 37°C, cultures were induced at 18°C using 0.3 mM IPTG before being purified under native and denaturing conditions. Under native conditions for all protein, pellets were resuspended in a buffer containing 20 mM Tris–HCl pH 8.0, 100 mM NaCl, 35 mM imidazole and 2 mM βME and supplemented with 1 mM PMSF and cOmplete EDTA‐free (Sigma) before lysing by sonication. Clarified lysates were applied onto a HisTrap® HP column. For His‐CAL11–160, His‐CAL11–50 and His‐CAL11–160‐LL‐841–979, HisTrap® HP columns were then washed with 60 CV of lysis buffer, 20 CV of 20 mM Tris–HCl pH 8.0, 1 M NaCl, 35 mM imidazole, 50 mM KCl, 10 mM MgCl2, 2 mM ATP and 2 mM βME and then 10 CV of lysis buffer. Proteins were then eluted in 20 mM Tris–HCl pH 8.0, 100 mM NaCl, 500 mM imidazole and 2 mM βME. For His‐SUMO‐CAL1841–979 and His‐CENP‐C1264–1411, HisTrap® HP columns were washed with 80 CV of lysis buffer. Protein was eluted using 20 mM Tris–HCl pH 8.0, 100 mM NaCl, 500 mM imidazole and 2 mM βME, and fractions containing protein were dialysed overnight against 20 mM Tris–HCl pH 8.0, 500 mM NaCl and 2 mM DTT for His‐CENP‐C1264–1411 and 20 mM Tris–HCl pH 8.0, 100 mM NaCl and 2 mM DTT for His‐SUMO‐CAL1841–979. His‐SUMO‐CAL1841–979 was applied to a HiTrap® Q HP column and eluted with a gradient of 20 mM Tris–HCl (pH 8.0), 1 M NaCl and 2 mM DTT.His‐CAL1Tags were removed by incubation with 3C or TEV overnight followed by a reverse affinity step to remove His‐SUMO. Proteins were purified by SEC using either a Superdex 200 increase 10/300 GL, Superdex 75 10/300 GL or Superdex 75 increase 10/300 GL column .1–160, His‐CAL11–50 and His‐CAL11–160‐LL‐841–979, pellets were suspended in 2 ml/g of wet pellet of 20 mM Tris–HCl pH 8.0, 500 mM NaCl, 25 mM imidazole, 7 M urea and 2 mM βME, and incubated for 1 h at 4°C with rotation. DNA was sheared by sonication before clarifying by centrifugation. Lysate was then incubated with 10 ml of HisPur™ Ni‐NTA resin (Thermo Fisher Scientific) overnight, before washing with 60 CV of buffer, 20 CV of 20 mM Tris–HCl (pH 8.0), 1 M NaCl, 25 mM imidazole, 7 M urea and 2 mM βME, 10 CV of 500 mM NaCl buffer before eluting with 20 mM Tris–HCl (pH 8.0), 500 mM NaCl, 500 mM imidazole, 7 M guanidine HCl and 2 mM βME.For denatured His‐CAL1To refold histones with and without CAL1, histones were resuspended in 20 mM Tris–HCl pH 7.5, 7 M guanidine HCl and 2 mM βME and mixed with equimolar amounts of proteins needed. Proteins were then dialysed for 2 h at 4°C against 200 ml of 20 mM Tris–HCl pH 7.5, 7 M guanidine HCl and 2 mM βME; then, 2 l of 10 mM Tris–HCl pH 7.5, 2 M NaCl, 1 mM EDTA and 5 mM βME was slowly added overnight using a peristaltic pump. If needed, refolded protein was further dialysed against a lower salt concentration solvent; if not, complexes were purified by SEC using either a Superdex 200 increase 10/300 GL or Superdex 75 increase 10/300 GL column .1–160‐CENP‐A101–225‐H4, 27 mg/ml of complex in a buffer of 20 mM Tris–HCl pH 8.0, 1 M NaCl and 5 mM DTT crystallised after about a year in 0.01 M Cobalt (II) chloride hexahydrate, 0.1 M MES pH 6.5 and 1.8 M ammonium sulphate at 18°C. For CAL11–160‐CENP‐A144–225‐H4, protein in 20 mM Tris–HCl pH 8.0, 1 M NaCl and 2 mM DTT was concentrated to 17 mg/ml and crystallised in C11, 0.2 M lithium sulphate, 0.1 M Tris pH 8.5 and 30% PEG 4000. An optimisation screen was set up in a 24‐well format, using half the original concentrations of protein. Tris–HCl pH 8.5 was kept at 0.1 M, while concentrations of lithium sulphate varied from 0.1 to 0.3 M and PEG 4000 varied from 24 to 34%.Crystallisation trials were performed using a nanolitre Crystal Gryphon robot (Art Robbins) and grown by vapour diffusion methods. For CAL11264–1411 was screened at 15 mg/ml in 20 mM Tris–HCl pH 8.0, 500 mM NaCl and 2 mM DTT against several commercial and homemade screens at 18°C. Crystals were obtained in around 13% of all conditions tested. His‐CENP‐C1264–1411‐CAL1841–979 complex was made in 20 mM Tris–HCl pH 8.0, 100 mM NaCl and 2 mM DTT and used with Structure 1 + 2 and JCSG+ (Molecular Dimensions) at 15 mg/ml at 4°C. Crystals were briefly transferred to a cryoprotectant solution (either oil or the mother liquor supplemented with 40% peg 3350) before directly flash cooled in liquid nitrogen and analysed on beamlines i03 and i04‐1 at the Diamond Light Source .Cleaved CENP‐C1–160–CENP‐A/H4 form I, CENP‐C1264–1411; CENP‐C1264–1411‐CAL1841–979) and i04‐1 (CAL11–160–CENP‐A/H4 form II), at the Diamond Light Source . Data were processed using the software pipeline available at Diamond Light Source that relies on XDS, CCP4, CCTBX, AutoPROC and STARANISO , CENP‐C1264–1411 and CENP‐C1264–1411‐CAL1841–979 structures were determined by molecular replacement with the program PHASER . Data collection, phasing and refinement statistics are shown in Table Diffraction data were collected on beamlines i03  run at 180 V for 1 h in MES buffer. Gels were then stained with Coomassie Blue, and scanned gel images were analysed and quantified with ImageJ.Ni‐NTA pull‐down assays were performed using His‐CAL1Size‐exclusion chromatography  coupled to UV, static light scattering and refractive index detection  was used to determine the molecular mass of proteins and protein complexes in solution. Injections of 100 μl of 1–5 mg/ml material were used.1–160‐CENP‐A101–225‐H4 (∂A280 nm/∂c = 0.67 AU.ml/mg), His‐CAL11–160‐CENP‐A144–225‐H4 (∂A280 nm/∂c = 0.75 AU.ml/mg) and His‐CAL11–50‐CENP‐A101–225‐H4 (∂A280 nm/∂c = 0.55 AU.ml/mg) were run on a Superdex 200 increase 10/300 GL size‐exclusion column pre‐equilibrated in 50 mM HEPES pH 8.0, 2 M NaCl and 1 mM TCEP at 22°C with a flow rate of 0.5 ml/min. His‐CENP‐C1264–1411 L1357E/M1407E (∂A280 nm/∂c = 0.75 AU.ml/mg) was run on a Superdex 200 increase 10/300 GL size‐exclusion column pre‐equilibrated in 50 mM HEPES pH 8.0, 300 mM NaCl and 1 mM TCEP at 22°C with a flow rate of 0.5 ml/min. CENP‐C1264–1411 (∂A280 nm/∂c = 0.84 AU.ml/mg) was run at 4°C on a Superdex 75 increase 10/300 GL size‐exclusion column pre‐equilibrated in 50 mM HEPES pH 8.0, 100 mM NaCl and 1 mM TCEP.For His‐CAL1280 nm were analysed by a homo‐polymer model  using the parameters stated for each protein, ∂n/∂c = 0.185 ml/g and buffer RI value of 1.335. The mean standard error in the mass accuracy determined for a range of protein–protein complexes spanning the mass range of 6–600 kDa is ± 1.9%.Light scattering, refractive index (RI) and A3 was used to cross‐link 10 μg of protein for 2 h at RT. The reactions were quenched with final concentration 100 mM Tris–HCl or 5 mM ammonium bicarbonate, respectively, before separation on Bolt™ 4–12% Bis‐Tris Plus gels (Invitrogen). Following previously established protocol  and 66 μg sulpho‐NHS (Thermo Fisher Scientific) were used to cross‐link 10 μg of protein for 1.5 h at RT. 30 μg of BSet al (5 cells per well. Cells were transfected using X‐tremeGENE DNA Transfection Reagent (Roche) according to the manufacturer's instructions, using 200 ng of plasmid DNA. Transfected cells were analysed by immunofluorescence 72 h post‐transfection.Schneider S2 cells containing the LacO array (L2‐4_LacO_LexA_Clone11) were generated as described in Mendiburo et al . Schneidet al, 2 incubator. Cells were seeded in 10 cm dishes, a day prior to transfection at a density of 2.5 × 106 cells per well. Transfections were performed with Lipofectamine 3000 (Life Technologies) according to the manufacturer's instructions, using 15 μg of plasmid DNA and Opti‐MEM I reduced serum medium (Life Technologies). Next day, cells were washed once with 1×DPBS, trypsinised, counted and re‐plated on poly‐lysine‐coated coverslips in 6‐well plates at a density of 106 cells per well. Downstream experiments were performed 3 days post‐transfection.U2OS cells containing 200 copies of an array of 256 tandem repeats of the 17 bp LacO sequence on chromosome 1  overnight at 4°C in a humidified chamber and were used in 1:100 dilution unless otherwise stated: myc (Abcam‐ab9106), V5 (Invitrogen‐R96025) and HA . Secondary antibodies coupled to Alexa Fluor 555 and 647 (Invitrogen) were used at 1:100 dilutions. Counterstaining of DNA was performed with DAPI (5 μg/ml), and coverslips were mounted on the slides with 30 μl of SlowFade® Gold antifade reagent.Cells were washed once in PBS and then fixed with 3.7% formaldehyde in 0.1% Triton X‐100 in 1× PBS (PBST) for 8 min at RT. Following fixation, the slides were washed once in PBST and then blocked in Image‐iTz‐stacks of 0.2 μm increments, using a 100× oil immersion objective on a DeltaVision RT Elite Microscope and a CoolSNAP HQ Monochrome camera. All images were deconvolved using the aggressive deconvolution mode on a SoftWorx Explorer Suite (Applied Precision) and are shown as quick projections of maximum intensity. For U2OS cells, the mean fluorescence intensity of the protein of interest was measured at the LacO spot, and then the mean fluorescence intensity in the nucleus (background) was subtracted from this value. For S2 cells, the mean fluorescence intensity of the protein of interest was measured at the LacO spot, and then the mean fluorescence intensity of three spots around the LacO spot was subtracted from this value. 25–50 cells were analysed per biological replicate, and a minimum of three independent biological replicates were quantified per experiment.All IF images were taken as 50 et al, et al, Sedimentation velocity and SE experiments were performed using a Beckman Coulter XL‐I analytical ultracentrifuge equipped with an An‐50 Ti eight‐hole rotor. Depending on their concentration, samples were loaded into 12 (low concentration) or 3 mm (high concentration) pathlength charcoal‐filled epon double‐sector centrepieces, sandwiched between two sapphire windows. For SV, samples were equilibrated at 4°C in vacuum for 6 h before running at 49 k rpm. For SE, data were recorded at 26 k rpm. The laser delay, brightness and contrast were pre‐adjusted at 3 k rpm to acquire the best quality interference fringes. Data were collected using Rayleigh interference and absorbance optics recording radial intensity or absorbance at 280 nm. For SV, data were recorded between radial positions of 5.65 and 7.25 cm, with a radial resolution of 0.005 cm and a time interval of 7 min, and analysed with the program SEDFIT Schuck,  using a t‐test or Mann–Whitney test. For each statistical test, P‐value of < 0.05 was considered significant.Data are representative of at least three independent experiments, unless otherwise stated. Statistics were performed using GraphPad Prism, version 7.0e , using an unpaired two‐tailed AAJ and PH conceived the project. BM‐P, VL, PH and AAJ designed experiments. BM‐P,VL, OB, MAA and JZ performed experiments. JR provided expertise and feedback. BM‐P and AAJ wrote the manuscript with input from all authors.The authors declare that they have no conflict of interest.AppendixClick here for additional data file.Expanded View Figures PDFClick here for additional data file.Review Process FileClick here for additional data file.


In the crystal structure of the title compound intermolecular hydrogen-bonding interactions and weak C—H⋯π interactions between the constituents lead to the formation of a three-dimensional network. Hirshfeld surface analysis revealed that H⋯H interactions dominate the crystal packing. 22H17NO2·C3H7NO, was synthesized by condensation of an aromatic aldehyde with a secondary amine and subsequent reduction. It was crystallized from a dimethylformamide solution as a monosolvate, C22H17NO2·C3H7NO. The aromatic molecule is non-planar with a dihedral angle between the mean planes of the aniline moiety and the methyl anthracene moiety of 81.36 (8)°. The torsion angle of the Caryl—CH2—NH—Caryl backbone is 175.9 (2)°. The crystal structure exhibits a three-dimensional supramolecular network, resulting from hydrogen-bonding interactions between the carboxylic OH group and the solvent O atom as well as between the amine functionality and the O atom of the carboxylic group and additional C—H⋯π interactions. Hirshfeld surface analysis was performed to quantify the intermolecular interactions.The title compound, C Schiff bases belong to a class of organic compounds that are formed by the condensation reaction of a carbonyl carbon with an aliphatic/aromatic amine, resulting in the formation of a characteristic imine bond (–HC=N–). Many Schiff bases exhibit activities of biological and pharmaceutical significance. Moreover, Schiff bases are actively used as organic linkers for building metal complexes with interesting properties.et al., 2017et al., 2014et al., 2012), antimicrobial . The title compound crystallizes with a dimethylformamide (DMF) solvent molecule in a 1:1: ratio. Both anthraldehyde and PABA have shown anticancer (Pavitha aryl—CH2—NH—Caryl backbone (C9—C8—N1—C5) is 175.9 (2)°. The C8—N1 bond length of 1.452 (3) Å is in agreement with the corresponding bond length of 1.457 (3) Å in the solvent-free compound isophthalic acid containing gadolinium  = 1.2Ueq(C).Crystal data, data collection and structure refinement details are summarized in Table 210.1107/S2056989020005393/wm5548sup1.cifCrystal structure: contains datablock(s) I. DOI: 10.1107/S2056989020005393/wm5548Isup2.hklStructure factors: contains datablock(s) I. DOI: 1982147CCDC reference:  crystallographic information; 3D view; checkCIF reportAdditional supporting information:


N-heterocyclic carbene precursor, zwitterionic 3,3′-bis(propane-1-sulfonate) crystallized as its dihydrate and was characterized by single-crystal X-ray diffraction, revealing point group symmetry A known  16H26N4O6S2·2H2O, a water-soluble di-N-heterocyclic carbene ligand precursor was determined using a single crystal grown by the slow cooling of a hot N,N-dimethylformamide solution of the compound. The dihydrate crystallizes in the monoclinic space group P21/c, with half of the zwitterionic molecule and one water molecule of crystallization in the asymmetric unit. The remaining part of the molecule is completed by inversion symmetry. In the molecule, the imidazole ring planes are parallel with a plane-to-plane distance of 2.741 (2) Å. The supramolecular network is consolidated by hydrogen bonds of medium strength between the zwitterionic molecules and the water molecules of crystallization, as well as by π–π stacking interactions between the imidazole rings of neighbouring molecules and C—H⋯O hydrogen-bonding interactions.The crystal structure of the title compound, C To the best of our knowledge, this is the first crystal structure determination of an alkylene-bridged di-imidazolium salt with ω-propylsulfonate wingtips. Compound 1 is known from the literature bis. No molecules of the solvent, DMF, from which the crystals were obtained, are built into the lattice.The di-1  Å, S1—O1 = 1.446 (2) Å, S1—O2 = 1.450 (2) Å, S1—O3 = 1.453 (2) Å, and angles O1—S1—O2 = 112.16 (14)°, O1—S1—O3 = 111.80 (14)°, and O2—S1—O3 = 112.80 (15)°. As a result of the point group symmetry The zwitterionic molecule of 1 Fig. 2 is compo Å Fig. 3 from eacx, 1 − y, 1 − z; centroid-to-centroid distance of 3.9541 (17) Å, slippage 1.622 Å, Fig. 5The water molecules bridge adjacent zwitterionic molecules through hydrogen bonds of medium strength with sulfonate O atoms as acceptor groups into ribbons aligned parallel to [001] Table 1. π–π staet al., 2016N-heterocyclic carbene ligand precursor molecules where two N-ω-sulfonatopropyl-imidazolium units are connected through an α,ω-alkylene bridge. Crystals of similar sulfoalkyl-imidazolium di-NHC precursors containing aromatic linkers have been grown by Kohmoto et al.  were also reported.A search of the Cambridge Structural Database ], refcode: YAVROF, and [Pd(2)2], refcode: YAVXAX, crystallize in space group type PP21/c.The Pd complexes [PdCl1 was synthesized according to the method of Papini et al. . Analytical data: 13C{1H}-NMR  δ [ppm], 135.6, 122.5, 48.8, 47.8, 47.2, 26.2, 25.0; ESI–MS , m/z observed 435.1359, calculated value for C16H27N4O6S2, ([M - H]+): 435.1367). For recrystallization, 1 was suspended in DMF and heated to approximately 373 K, then filtered and left overnight to slowly cool down to room temperature. Single crystals, suitable for X-ray analysis, were obtained as colourless prisms after storing the solution in open glass vials in a refrigerator at 278 K. A possible source of water is the employed DMF, which is hygroscopic and easily adsorbs water from a humid atmosphere. The same type of prismatic crystals were also grown from hot water, revealing a very similar unit cell. However, these crystals were of poor quality, and the best Rint value was very high, 0.19.Compound  al. 2009. 4.4 mmoUiso(H) = 1.5Ueq(O).Crystal data, and details of data collection and structure refinement are summarized in Table 210.1107/S2056989020009779/wm5571sup1.cifCrystal structure: contains datablock(s) I. DOI: Click here for additional data file.10.1107/S2056989020009779/wm5571Isup3.cdxSupporting information file. DOI: 10.1107/S2056989020009779/wm5571Isup4.hklStructure factors: contains datablock(s) I. DOI: 2017141CCDC reference:  crystallographic information; 3D view; checkCIF reportAdditional supporting information:


Nature Communications 10.1038/s41467-020-14509-4, published online 31 January 2020.Correction to: The original version of this Article contained an error in the information provided in the legend for Supplementary Fig. 4D. The text should read: 1 = UA-GalNAc4S; 2 = UA-GalNAc4S incubated with B.theta PBS washed cells for 1h; 3 = UA-GalNAc4S incubated with B.theta PBS washed cell for 24h; 4 = UA-GalNAc4S incubated with sonicated B.theta PBS washed cells for 1h; 5 = UA-GalNAc4S incubated with sonicated B.theta PBS washed cell for 24h; 6 = GalNAc; 7 = GalNAc6S; 8 = GalNAc6S incubated with B.theta PBS washed cells for 1h; 9 = GalNAc6S incubated with B.theta PBS washed cells for 24h; 10 = GalNAc6S incubated with sonicated B.theta PBS washed cell for 1h and 11 = GalNAc6S incubated with sonicated B.theta PBS washed cells for 24.This has been corrected in both the PDF and HTML versions of the Article.


II‐mediated base pair than a rigid HgII‐mediated base pair within the base stack of a double helix.Oligonucleotides incorporating a central C‐nucleoside with either a rigid or flexible benzaldoxime base moiety have been synthesized, and the hybridization properties of their metallacyclic derivatives have been studied by UV melting experiments. In all cases, the metallated duplexes were less stable than their unmetallated counterparts, and the metallacyclic nucleobases did not show a clear preference for any of the canonical nucleobases as a base‐pairing partner. With palladated oligonucleotides, increased flexibility translated to less severe destabilization, whereas the opposite was true for the mercurated oligonucleotides; this reflects the greater difficulties in accommodating a rigid Pd Take the strain: A flexible PdII‐mediated base pair of a benzaldoxime palladacycle disrupts oligonucleotide hybridization less than its rigid analogue, whereas the opposite is true for HgII‐mediated base pairs. With a base pair of an incompatible geometry, increased flexibility alleviates some of the strain; with a strain‐free base pair it merely leads to an increased entropic penalty of hybridization. II for the canonical nucleobasesDouble‐helical oligonucleotides incorporating metal‐mediated base pairsII‐mediated base pairs have been reported since 1999,II‐mediated base pairing remained elusive for a long time and even today the most compelling results have been obtained on duplexes having the PdII‐mediated base pair(s) at a terminal position.II‐mediated base pair could stem from suboptimal geometries of the base pairs reported so far. Indeed, a thorough study of PdII‐mediated base pairing between terpyridine and various azoles has revealed that a planar base pair was only formed with 1‐methyltetrazole, having no substituents (not even hydrogens) facing the PdII‐terpyridine complex.II center somewhat more exposed than the PdII‐terpyridine complex but achieving a coplanar orientation of the palladacycle and the canonical nucleobase may still be difficult. As the steric requirements for base pairing are less strict at the termini than within the base stack, the stabilization provided by the high binding affinity of PdII is not offset by strain imposed by the unfavorable geometry of the PdII‐mediated base pair.Although a number of PdII ion in the same position but the former ‐3‐[(tert‐butyldimethylsilyl)oxy]‐2,3‐dihydrofuran‐2‐yl}methanol and 2‐(4‐bromophenyl)‐1,3‐dioxane. Compound 1 was then desilylated to the ketone intermediate 2 which, in turn, was reduced to the protected C‐nucleoside 3. 5′‐Dimethoxytritylation of compound 3 afforded intermediate 4 and subsequent 3′‐phosphitylation the phosphoramidite building block 5. Synthesis of compound 5 has been described previouslySynthesis of the protected benzaldehyde C‐nucleoside 8 and its phosphoramidite building block 10 were synthesized following the pathway outlined in Scheme 7 was first prepared by a Mitsunobu reaction between 3,5‐di‐O‐benzyl‐C‐hydroxymethyl‐2‐deoxy‐β‐d‐ribofuranose (6)N‐hydroxhphthalimide. Removal of the benzyl protections by Pd(OH)2/C‐catalyzed hydrogenation afforded compound 8. Preparation of compound 8 has been reported previously8 was 5′‐dimethoxytritylated to give compound 9 which, in turn, was 3′‐phosphitylated to give the phosphoramidite building block 10. These last two steps were carried out as described in the literature.Phthaloyl‐protected aminooxymethyl C‐nucleoside ON1x, ON1y and ON1b were assembled on an automated DNA/RNA synthesizer by the conventional phosphoramidite strategy, employing an extended coupling time for building blocks 5 and 10. Normal (ca. 99 %) coupling yields were observed throughout the synthesis. The acetal and phthaloyl protections of the benzaldehyde and aminooxymethyl residues were removed on‐support by treatment with dichloroacetic acid in wet CH2Cl2 or hydrazine acetate in pyridine, respectively. The newly exposed aminooxy function was immediately allowed to react with either 3‐hydroxybenzaldehyde or benzaldehyde. Finally, oligonucleotides ON1x, ON1y and ON1b were released from the solid support and deprotected by conventional ammonolysis and purified by RP‐HPLC. ON1x eluted as two barely separable peaks, presumably attributable to E and Z isomers of the oxime bond. The stereoselectivity of oximation of benzaldehydes is known to be highly sensitive to the reaction conditionsortho‐mercuration), the oligonucleotide environment probably affects as well. Unfortunately, the isolated amounts of the putative isomers of ON1x were not sufficient for more detailed characterization.Table ON1b was treated with an aqueous solution of methoxylamine to convert the central benzaldehyde residue into an O‐methylbenzaldoxime residue. Oligonucleotide ON1z thus obtained was purified by RP‐HPLC and cyclopalladated in an aqueous solution of Li2PdCl4. The product mixture was fractioned on RP‐HPLC to afford the palladacyclic oligonucleotide ON1z−Pd. Finally, oligonucleotides ON1b, ON1x, ON1y, ON1z and ON1z−Pd were characterized by ESI‐TOF‐MS and quantified by UV spectrophotometry. Synthesis of the modified oligonucleotides ON1x−Hg and ON1y−Pd has been described previously.ON1x, ON1x−Hg, ON1y, ON1y−Pd, ON1z and ON1z−Pd were studied by conventional UV melting experiments. Each modified oligonucleotide was mixed with each of the unmodified counterparts ON2a, ON2c, ON2g and ON2t, pairing the artificial residue with adenine, cytosine, guanine or thymine, respectively. The oligonucleotide concentrations of the samples were 1.0 μM, the pH 7.4 (20 mM cacodylate buffer) and the ionic strength 0.10 M (adjusted with sodium perchlorate). Melting profiles for unmodified duplexes of otherwise identical sequence but with cytosine in place of the modified residue have been reported previously.Hybridization properties of the modified oligonucleotides ON1x ⋅ ON2t, ON1x−Hg ⋅ ON2t, ON1y ⋅ ON2t, ON1y−Pd ⋅ ON2t, ON1z ⋅ ON2t and ON1z−Pd ⋅ ON2t as representative examples . With the notable exception of ON1z−Pd, monophasic sigmoidal melting curves were observed in most cases. Melting temperatures of the unmetallated duplexes formed by ON1y, ON1z and the faster‐eluting isomer of ON1x ranged from 33 to 36 °C, typical for 11‐mer oligodeoxynucleotides containing a single mismatch . Apparently PdII‐mediated base pairing by the benzaldoxime palladacycles of ON1y−Pd and ON1z−Pd causes strain that in the former case is to some extent relieved by the flexible structure of the palladacycle but in the latter case prevents formation of a double helix. Disruption of Watson‐Crick base pairing by a neighboring metal‐mediated base pairing has been described previously in detail with Ag(I) as the bridging metal ion.Figure ON1x remained elusive as no consistent pattern of different enthalpies and entropies emerged. The relatively low stability of the duplexes formed by the mercurated oligonucleotide ON1x−Hg compared to respective duplexes incorporating a 5‐mercuricytosineON1x−Hg (500–600 J mol−1 K−1) than for its unmercurated counterpart ON1x (700–800 J mol−1 K−1), it was still considerably higher than the respective value reported for those more stable mercurated duplexes (200–400 J mol−1 K−1). HgII‐mediated base pairing generally leads to a reduced entropic penalty of hybridization owing to dehydration of the bridging HgII ionON1x−Hg some of this effect is offset by restricted rotation of several σ bonds. The enthalpies of hybridization were similar for the duplexes formed by ON1x−Hg and those containing 5‐mercuricytosine, approximately 200 kJ mol−1.When applicable, thermodynamic parameters of hybridization were determined as described previouslyII‐mediated base pairing, detailed thermodynamic data on PdII‐mediated base pairing is scanty but reanalysis of UV melting profiles reported previously for octamer duplexes with an unpalladated or palladated benzylamine attached to the 5′ terminus through a flexible linker revealed more negative enthalpies and entropies of hybridization for the palladated oligonucleotides.II‐mediated base pairing itself is an enthalpy‐driven process, whereas the entropic penalty is consistent with conformational restriction of the flexible linker. In the present case, however, both the enthalpies and the entropies of hybridization were less negative with ON1y−Pd than with ON1y and the differences were actually considerably larger than between ON1x−Hg and ON1x. This result, while in apparent conflict with the data obtained on oligonucleotides featuring terminal palladacyclic modifications, could be understood if formation of the PdII‐mediated base prevented formation of some (in the case of ON1y−Pd) or all (in the case of ON1z−Pd) of the canonical Watson‐Crick base pairs.Compared to the well‐documented HgON1x−Hg and ON1y−Pd were largely similar except for ON1x−Hg ⋅ ON2g, in which case the signal at 250 nm was hardly detectable. With ON1z−Pd the spectra were much more distorted and the ellipticity lower, in line with the inability of this oligonucleotide to form a double helix with any of the unmodified counterparts at temperatures above 10 °C. Gradual thermal diminution of the Cotton effects, consistent with denaturation of the double helix, was observed with all of the duplexes studied.All samples were also analyzed CD spectropolarimetrically for more detailed information on the secondary structures adopted by the oligonucleotides. The spectra were recorded between 10 and 90 °C at 10 °C intervals. At the low end of the temperature range, the spectra of the unmetallated duplexes were characteristic of B‐type double helices, with negative and positive Cotton effects of nearly equal intensity at 250 and 280 nm, respectively (spectra presented in the Supporting Information). The corresponding spectra of the duplexes formed by II‐ or HgII‐mediated base pair. The oligonucleotide incorporating a flexible palladacyclic nucleoside formed more stable duplexes than its more rigid counterpart whereas comparison of the present data with those reported previously revealed the opposite to be true for oligonucleotides incorporating organomercury nucleosides. These results can be understood in terms of the different geometries of PdII‐ and HgII‐mediated base pairs. The former may be unable to assume the coplanar orientation preferred within the base stack of a double helix and in such a case a flexible structure might be able to alleviate some of the resulting strain. The latter, on the other hand, are usually nearly planar and geometrically very similar to canonical Watson‐Crick base pairs and in such a case increased flexibility will only result in an increased entropic penalty as the flexible structure is constrained within the base stack.Increased flexibility of the metallated nucleoside analog was found to have profoundly different effects on the melting temperatures of oligonucleotide duplexes containing a central PdGeneral methods: All experiments involving air and/or moisture sensitive compounds were performed using oven‐dried glassware under argon atmosphere. For preparation of HPLC elution buffers, freshly distilled triethylamine was used. Other commercially available chemicals were used without further purification unless otherwise stated. The solvents for organic synthesis were of reagent grade and dried over 4 Å molecular sieves. All reactions were monitored by thin layer chromatography (TLC), performed on Merck 60 (silica gel F254) plates. Chromatographic purification of products was accomplished using flash column chromatography on silica gel (230–400 mesh). 1H, 13C and 31P NMR spectra were recorded in deuterated solvents on a Bruker Biospin 500 or 600 MHz NMR spectrometer. Chemical shifts  are quoted relative to the residual solvent peak as internal standard. Mass spectra were recorded on a Bruker Daltonics micrOTOF‐Q ESI mass spectrometer.Oligonucleotide synthesis: Synthesis of the modified oligonucleotides ON1x−Hg and ON1y−Pd has been described previously. The other modified oligonucleotides  were assembled on an Applied Biosystems 3400 automated DNA/RNA synthesizer by conventional phosphoramidite strategy. For the acetal protected benzaldehyde and the phtahaloyl‐protected aminooxymethyl C‐nucleoside phosphoramidite building blocks 2 and 8, the coupling time was extended to 300 s. Based on trityl response, all couplings proceeded with normal efficiency. Removal of the acetal protecting group of the benzaldehyde residue was carried out on‐support by treatment with 2 % dichloroacetic acid and 1 % H2O in CH2Cl2 at 25 °C for 2 h.2Cl2 (3.0 mL) or neat benzaldehyde  to eventually afford oligonucleotides ON1x and ON1y, respectively. Finally, oligonucleotides ON1x, ON1y and ON1b were released from the solid support and the phosphate and base moieties were deprotected by incubation in 25 % aqueous ammonia at 55 °C for 12 h and purified by RP‐HPLC on a Hypersil ODS C18 column  eluting with a linear gradient of MeCN (5–30 % over 30 min) in 50 mM aqueous triethylammonium acetate. The flow rate was 1.0 mL min−1 and the detection wavelength 260 nm.ON1b was converted into an O‐methylbenzaldoxime residue by treatment with a mixture of methoxylamine hydrochloride (1.0 μmol) and NaOAc (1.0 μmol) in H2O (100 μL) at 25 °C for 12 h. The crude oligonucleotide ON1z thus obtained was purified by RP‐HPLC as described above. For cyclopalladation, ON1z (40 nmol), Li2PdCl4 (60 nmol) and NaOAc (240 nmol) were dissolved in H2O (10 μL) and the resulting mixture was incubated at 55 °C for 40 h. The crude product ON1z−Pd was purified by RP‐HPLC as described above. As reported previously for other cyclopalladated oligonucleotides,ON1z−Pd eluted as a broad and convoluted peak even after purification, presumably due to the relatively slow ligand‐exchange of PdII giving rise to a variety of slow‐equilibrating structures involving intra‐ as well as interstrand PdII‐mediated base pairing. All of the newly synthesized oligonucleotides  were characterized by ESI‐TOF‐MS and quantified UV spectrophotometrically using molar absorptivities calculated by an implementation of the nearest‐neighbors method.The central benzaldehyde residue of oligonucleotide UV melting experiments: UV melting profiles were acquired on a PerkinElmer Lambda 35 UV‐Vis spectrometer equipped with a Peltier temperature control unit, using quartz glass cuvettes with 10.00 mm optical path length. The samples were prepared by mixing appropriate oligonucleotides (1.0 μM) in 20 mM cacodylate buffer (pH 7.4), the ionic strength of which was adjusted to 0.10 M with NaClO4. Before each experiment, the samples were annealed by heating to 90 °C for 30 min and then allowing to gradually cool down to room temperature. Three denaturing and renaturing ramps were performed  with each sample and absorbance at λ=260 nm was recorded at 0.5 °C intervals. The melting temperatures were determined as inflection points on the UV melting curves.CD experiments: CD spectra were recorded on an Applied Photophysics Chirascan spectropolarimeter equipped with a Peltier temperature control unit, using quartz glass cuvettes with 10.00 mm optical path length. Sample preparation was identical to the procedures used for the UV melting experiments above. Nine spectra were acquired for each sample at 10 °C intervals over T=10–90 °C and λ=200–400 nm. Before each measurement, the samples were allowed to equilibrate at the appropriate temperature for either 120 s  or 1800 s .O‐(tert‐Butyldimethylsilyl)‐2‐deoxy‐2,3‐didehydro‐β‐d‐erythro‐pentofuranosyl]phenyl}‐1,3‐dioxane (1)2‐{4‐‐2,3‐dihydrofuran‐2‐yl}methanol , Bu4NBr , DIPEA  and (tBu3P)2Pd(0)  were taken in a round‐bottomed flask and purged with argon. 1,4‐dioxane  was added and the mixture stirred at 70 °C for 16 h. The volatiles were evaporated and the residue was co‐evaporated twice from toluene. The crude product was purified by silica gel flash column chromatography  affording compound 1  as a colorless foam. 1H NMR : δ=7.48 , 7.39 , 5.74 , 5.50 , 4.83 , 4.62 , 4.25 , 3.97 , 3.74–3.66 , 2.22 , 1.95 , 1.43 , 0.96 ), 0.24 , 0.21 . 13C NMR : δ=151.5 (C3′), 143.0 (C1), 138.8 (C4), 127.1 (C3 & C5), 126.3 (C2 & C6), 101.4 (dioxane−C1), 101.3 (C2′), 84.6 (C4′), 83.3 (C1′), 67.3 (dioxane−C3 & C5), 63.0 (C5′), 25.8 (dioxane−C5), 25.6 (SiC(CH3)3), 18.1 (SiC(CH3)3), −4.9 (SiCH3), −5.0 (SiCH3). HRMS (ESI+): m/z: calcd for C21H32O5SiNa [M+Na]+: 415.1911; found: 415.1894.R,5R)‐5‐(Hydroxymethyl)‐4‐oxotetrahydrofuran‐2‐yl]phenyl}‐1,3‐dioxane (2)2‐{4‐+: 301.1046; found: 301.1045.d‐erythro‐pentofuranosyl)phenyl]‐1,3‐dioxane (3)2‐+: 303.1203; found: 303.1202.O‐‐2‐deoxy‐β‐d‐erythro‐pentofuranosyl]phenyl}‐1,3‐dioxane (4)2‐{4‐+: 605.2510; found: 605.2511.O‐‐5‐: Et3N  and 2‐cyanoethyl‐N,N‐diisopropylchlorophosphoramidite  were added to a stirred solution of compound 4  in dry CH2Cl2 (3.0 mL) at 25 °C under N2. The reaction mixture was stirred for 2 h, after which it was diluted with CH2Cl2 (50 mL) and washed with saturated aq. NaHCO3 (50 mL). The organic layer was dried over Na2SO4 and evaporated to dryness. The residue was purified by silica gel flash column chromatography  affording compound 5  as a white foam. 1H NMR : δ=7.52–7.43 , 7.41–7.37 , 7.32–7.29 , 7.24 , 6.86–6.83 , 5.52 , 5.19 , 4.52 , 4.30–4.26 , 4.01 , 3.82 , 3.74–3.69 , 3.67–3.61 , 3.36 , 3.28 , 2.47 , 2.33 , 2.26 , 2.01 , 1.47 , 1.21 2), 1.18 2). 13C NMR : δ=158.5 (MeOPh−C4), 144.9 (Ph−C1), 142.5 (C1), 138.0 (C4), 136.2 (MeOPh−C1), 136.1 (MeOPh−C1), 130.18 (MeOPh−C2 & C6), 130.15 (MeOPh−C2 & C6), 128.3 (Ph−C3 & C5), 127.8 (Ph−C2 & C6), 126.7 (Ph−C4), 126.0 (C3 & C5), 125.9 (C2 & C6), 117.5 (CN), 113.1 (MeOPh−C3 & C5), 101.5 (dioxane−C1), 86.1 (CAr3), 86.0 , 80.1 (C1′), 75.7 , 67.4 (dioxane−C3 & C5), 64.1 (C5′), 58.3 , 55.2 (OCH3), 43.5 , 43.2 , 25.8 (dioxane−C4), 24.6 2), 24.5 2), 20.2 . 31P : δ=148.1. 1H NMR : δ=7.51–7.43 , 7.40–7.36 , 7.30–7.27 , 7.22 , 6.85–6.81 , 5.52 , 5.19 , 4.52 , 4.29 , 4.24 , 4.01 , 3.87–3.77 , 3.80 , 3.62–3.53 , 3.31 , 3.26 , 2.63 , 2.40 , 2.25 , 1.99 , 1.47 , 1.19 2), 1.10 2). 13C NMR : δ=158.4 (MeOPh−C4), 144.9 (Ph−C1), 142.5 (C1), 138.0 (C4), 136.13 (MeOPh−C1), 136.11 (MeOPh−C1), 130.17 (MeOPh−C2 & C6), 130.13 (MeOPh−C2 & C6), 128.3 (Ph−C3 & C5), 127.8 (Ph−C2 & C6), 126.7 (Ph−C4), 126.0 (C3 & C5), 125.8 (C2 & C6), 117.5 (CN), 113.1 (MeOPh−C3 & C5), 101.5 (dioxane−C1), 86.0 (CAr3), 85.7 , 80.0 (C1′), 76.1 , 67.4 (dioxane−C3 & C5), 64.2 (C5′), 58.4 , 55.2 (OCH3), 43.5 , 43.2 , 25.8 (dioxane−C4), 24.6 2), 24.5 2), 20.4 . 31P : δ=147.8. HRMS (ESI+): m/z: calcd for C45H55N2O8PK [M+K]+: 821.3328; found: 821.3325.O‐benzyl‐C‐phthalimidooxymethyl‐2‐deoxy‐β‐d‐ribofuranose (7)3,5‐Di‐: A solution of DIAD  in dry THF (8.0 mL) was added dropwise to a stirred solution of compound [613] , N‐hydroxyphthalimide  and PPh3  in dry THF (65.0 mL) at 0 °C. The resulting mixture was stirred at 0 °C for 2 h and then at 25 °C for 12 h, after which it was evaporated to dryness. The residue was suspended in H2O and extracted with EtOAc (2×50 mL). The combined extracts were dried over Na2SO4 and evaporated to dryness. The residue was purified by silica gel flash column chromatography  affording compound 7  as a colorless syrup. 1H NMR : δ=7.83 , 7.74 , 7.37–7.27 , 4.58 , 4.55 , 4.52 , 4.35–4.29 , 4.19 , 4.11 , 3.54 , 3.47 , 2.21 , 2.04 . 13C NMR : δ=163.3 (C=O), 138.2 (phenyl−C1), 138.1 (phenyl−C1), 134.4 , 129.0 , 128.43 (phenyl−C3 & C5), 128.37 (phenyl−C3 & C5), 127.70 (phenyl−C4), 127.68 (phenyl−C4), 127.60 (phenyl−C2 & C6), 127.57 (phenyl−C2 & C6), 123.5 , 84.1 (C4′), 80.6 (C3′), 79.6 (CH2ON), 76.4 (C1′), 73.4 (PhCH2), 71.2 (PhCH2), 70.9 (C5′), 34.6 (C2′). HRMS (ESI+): m/z: calcd for C28H27O6NNa [M+Na]+: 496.1731; found: 496.1728.Cd‐ribofuranose (8)‐phthalimidooxymethyl‐2‐deoxy‐β‐: Compound 7  was dissolved in EtOAc (50.0 mL). 20 % Pd(OH)2/C (190.0 mg) was added, the reaction vessel was filled with H2, and the reaction mixture was stirred at 25 °C under H2 atmosphere  for 1 h. The mixture was filtered through celite, and the filter was washed with EtOAc (2×20 mL). The combined filtrates were concentrated under vacuum and the residue was purified by silica gel flash column chromatography  affording compound 8  as colorless syrup. 1H NMR  δ=7.87–7.83 , 4.51 , 4.30–4.24 , 3.82 , 3.57–3.51 , 2.09–1.97 . δ=163.5 (C=O), 134.4 , 128.9 , 122.9 , 87.7 (C4′), 79.5 (CH2ON), 76.1 (C1′), 72.1 (C3′), 62.4 (C5′), 36.6 (C2′). m/z: calcd for C14H15O6NNa [M+Na]+: 316.0792; found: 316.0792.O‐‐C‐phthalimidooxymethyl‐2‐deoxy‐β‐d‐ribofuranose (9)5‐: Compound 9 was prepared from compound 8 as described in the literatureO‐[(2‐Cyanoethoxy)‐C‐phthalimidooxymethyl‐2‐deoxy‐β‐d‐ribofuranose (10)‐diisopropylamino)phosphinyl]‐5‐: Compound 10 was prepared from compound 9 as described in the literatureThe authors declare no conflict of interest.As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re‐organized for online delivery, but are not copy‐edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors.SupplementaryClick here for additional data file.


According to the literature, only small and twinned crystals of this double salt could be synthesised in a concentrated solution of MgCl2. For the crystal structure solution, single-crystal diffraction was carried out at a synchrotron radiation source. The monoclinic crystal structure (space group Cc) exhibits double chains of MgO octahedra linked by corners, connected by carbonate units and water molecules. The chloride ions are positioned between these double chains parallel to the (100) plane. Dry MgCO3·MgCl2·7H2O decomposes in the air to chlorartinite, Mg2(OH)Cl(CO3)·nH2O (n = 2 or 3). This work includes an extensive characterization of the title compound by powder X-ray diffraction, thermal analysis, SEM and vibrational spectroscopy.MgCO Therefore, the system MgCl2–MgCO3–H2O–CO2 has been investigated. The only nonbasic salt containing carbonate and chloride ions is MgCO3·MgCl2·7H2O , b = 11.30 (8), c = 9.22 (7) Å and β = 118.2 (6)°. Due to the low scattering power and the small size of the crystals, a crystal structure analysis of single crystals was not possible until now. Our own investigations should provide a better comprehension of the synthesis of MgCO3·MgCl2·7H2O and provide a more detailed characterization, including a crystal structure analysis.Schmittler 1964 conclude3·MgCl2·7H2O is based on the information of Schmidt . The suspension was stirred for 30 min. Afterwards, the undissolved MgO was filtered off. CO2 was bubbled through the stirred solution for 24 h at room temperature. The product was filtered off for further characterization.The synthesis of MgCOmidt 1960. MgO (1 3·MgCl2·7H2O was recovered from a droplet of its mother liquor and mounted rapidly in the cold (150 K) stream of nitrogen gas of the diffractometer.Data were collected on beamline SCD at the KIT Synchrotron Radiation Source using a Stoe IPDS diffractometer with monochromated radiation of λ = 0.8000 Å. A crystal of MgCOKα1 radiation, Vantec 1 detector). The samples were prepared as flat plates and measured at room temperature.PXRD patterns were taken for phase identification with a laboratory Bruker D8 Discover powder diffractometer in Bragg–Brentano set up .The thermal analysis was performed with a TG/DTA 220 instrument from Seiko Instruments (reference substance: AlThe SEM images were recorded with a TESCAN Vega 5130 SB instrument (20 kV accelerating voltage). The sample was coated with gold.−1, 256 scans per measurement) with KBr blanks was used.For the FT–IR spectrum, a Thermo Scientific Nicolet 380 FTIR spectrometer .max/λ = 0.56 Å−1 could be considered for the structure refinement. The crystal structure was solved by direct methods. The resulting structure solution exhibits a chemically reasonable atomic arrangement, distances, angles and displacement parameters.Crystal data, data collection and structure refinement details are given in Table 1Uiso values were set at 1.2Ueq(O) using a riding-model approximation.H atoms were placed in the positions indexed by difference Fourier maps and their The crystal exhibits nonmerohedral twinning. The matrix that relates the individual diffraction pattern was determined as . The reflections of both domains were integrated .3·MgCl2·7H2O Cl(CO3)·3H2O] begins within a few days 4(OH)2·4H2O] and amorphous phases. At 803 K the decomposition is complete and only MgO remains in the residue. The observed mass loss of 74.3 (1)% confirms the theoretical mass loss of 73.6%.The thermal decomposition of MgCOps Fig. 2. H2O, COmann 1964. A preci3·MgCl2·7H2O show thin needles (50 × 5 µm), which are twinned or even more intergrown Cl(CO3)·3H2O  plane, are located the chloride ions Cl1 and Cl2 Fig. 8. The poss Table 3. As a co3·MgCl2·7H2O and MgCO3·3H2O Cl(CO3)·2H2O (chlorartinite) and Mg2(OH)Cl(CO3)·H2O (dehydrated clorartinite), do not exhibit such double chains  I. DOI: 10.1107/S2053229620008153/uk3196Isup2.hklStructure factors: contains datablock(s) I. DOI: Click here for additional data file.10.1107/S2053229620008153/uk3196Isup3.cmlSupporting information file. DOI: 2010753CCDC reference:


In the ferrocene unit, the pentadienyl (Cps) rings are in an eclipsed conformation. Strong intermolecular π–π-stacking, CH(Cp)—C(Cp), and O(p-nitrophenyl)—HC(Cp) interactions consolidate the crystal structure.The title ferrocene derivative including an alkyne and a  5H5)2(C8NO2)], including an alkyne bonded to a para-nitrophenyl substituent, which was synthesized from a copper-free Sonogashira cross-coupling reaction between ethynylferrocene and 4-bromo-1-nitrobenzene, crystallizes in the P21/n space group. In the ferrocene unit, the pentadienyl (Cps) rings are in an eclipsed conformation. The angle of rotation between the substituted cyclopentadienyl ring and the p-nitrophenyl group is 6.19 (10)°, yielding a quasi-linear extension of the ferrocenyl substitution. Important intermolecular interactions arise from π–π stacking between the Cp rings and the p-nitrophenyl, from corners of the Cp rings that are perpendicularly aligned, and between the O atoms from the nitro substituent and carbons at the corners of the Cp rings, propagating along all three crystallographic axes.The title ferrocene derivative, [Fe(C The distances of the Fe1 atom from the centroids of the substituted and unsubstituted Cp rings are 1.6461 (8) and 1.6584 (8) Å, respectively. The Cg1—Fe1—Cg2 angle is 179.27°, where Cg1 and Cg2 are the centroids of substituted and unsubstituted Cp rings, respectively. The Cp rings in the ferrocene system are thus almost parallel, since the angle between the Cp ring planes is 1.03 (13)°. In addition, the Cp rings display a nearly eclipsed conformation with a slight deviation, as demonstrated by the average C—Cg1—Cg2—C torsion angle of 12.26°. The C—C bond distances in the Cp rings range from 1.417 (2) to 1.436 (2) Å, while the Fe—C bond lengths range between 2.038 (2) and 2.055 (2) Å.Fig. 1p-nitrophenyl substituent, allowing the formation of a zigzag structure; atom pairs involved relate C6(Cp) and C7(Cp) to C17(p-nitrophenyl) and C18(p-nitrophenyl) of a neighboring molecule, with short contacts of 3.340 (2) and 3.397 (2) Å, respectively. This interaction can be described as pairs of molecules being interrupted by two C3(Cp)⋯H8—C8(Cp) interactions from a different interconnected pair of perpendicularly oriented Fc moieties with short contact distances of 2.83 Å each. Short contacts from neighboring molecules establishing a distinctive interconnected pair between a corner of the Cp ring and one of the oxygen atoms from the p-nitrophenyl substituent yield a closed arrangement of atoms. Short contacts involve H6—C6(Cp)⋯O1(p-nitrophenyl) at a distance of 3.461 (2) Å. Another interconnection is found between adjacent p-nitrophenyl groups, yielding a ring arrangement involving pairs from H17—C17(p-nitrophenyl)⋯O2(p-nitrophenyl) with a distance of 2.727 (2) Å and pairs from O1(p-nitrophenyl)⋯H15—C15(p-nitrophenyl) with a distance of 2.716 (2) Å. In addition, a chain is formed by short contacts from the C17—H17(p-nitrophenyl)⋯O1(p-nitrophenyl) interaction belonging to the p-nitrophenyl substituent with a distance of 3.203 (19) Å. Numerical details of the hydrogen-bonding interactions are given in Table 1The title compound exhibits π–π stacking interactions between one of the Cp rings from the Fc moiety and the CrystalExplorer17  and those decomposed into nine individual interactions: H⋯H , C⋯H/ H⋯C , O⋯H/ H⋯O , C⋯C , C⋯O/O⋯C , C⋯N/N⋯C , N⋯O/O⋯N , O⋯O  and N⋯H/H⋯N . The Hirshfeld surface analysis for the title compound indicates that the most significant contributions arise from H⋯H and C⋯H contacts 2 (0.01 mmol), Et3N (2 mmol) and 4-bromo-1-nitrobenzene (1.0 mmol) to a 25 mL round-bottom flask, followed by the addition of DMF (1.0 mL) by syringe. The reaction was stirred for 1 h at 353 K. The reaction was stopped and crashed out with 20 mL of cold distilled water, then the solid was vacuum filtrated, and chromatographed [silica (heptane–ethyl acetate/7:3)] to afford the pure compound, 70% yield. Dark-red crystals suitable for X-ray diffraction were obtained by the slow evaporation of CDCl3 solution of the title compound at room temperature. NMR analyses were performed on a Bruker AV-700 spectrometer by using CDCl3 99.9% pure as a solvent and Me4Si as external standard.1H NMR : 4.26 , 4.32 , 4.55 , 7.59 , 8.18 . 13C NMR : 63.6, 69.6, 70.1, 71.8, 84.5, 95.2, 123.6, 131.1, 131.8, 146.4. IR : 2200 (C≡C). Electrochemistry: .The title compound was prepared by adding ethynylferrocene (1.0 mmol), PdClUiso(H) = 1.2Ueq(C).Crystal data, data collection and structure refinement details are summarized in Table 310.1107/S2056989020010336/dj2003sup1.cifCrystal structure: contains datablock(s) I. DOI: 10.1107/S2056989020010336/dj2003Isup2.hklStructure factors: contains datablock(s) I. DOI: 1991635CCDC reference:  crystallographic information; 3D view; checkCIF reportAdditional supporting information:


Figure 6 Liver control [1] appears identical to Fig. 10 liver control [2]Figure 6 Lung PEG-NPs [1] appears identical to Fig. 10 lung PEG-CF [2]Figure 6 Spleen control [1] appears identical to Fig. 10 spleen control [2]Figure 6 Spleen treatment [1] appears identical to Fig. 10 spleen treatment [2]Figure 7A [1] appears to be identical but in a different order to Fig. 6A all panels [3]Figure 7B [1] appears identical to Fig. 6B [3]Figure 7D [1] appears identical to Fig. 6D [3] using a different scaleFigure 7C [1] appears identical to Fig. 6E [3] using a different scaleAll authors agree with this retraction.The authors have retracted their article  because


Type 1 diabetes (T1D) and celiac disease (CD) share common genetic loci, mainly within the human leukocyte antigen (HLA) class II complex. Extended genotyping of HLA class II alleles and their potential risk for developing both diseases remains to be studied. The present study compared extended HLA‐class II gene polymorphisms in children with T1D, CD, and a subgroup diagnosed with both diseases (T1D w/CD).Next‐generation targeted sequencing (NGTS) of HLA‐DRB3, DRB4, DRB5, DRB1, DQA1, DQB1, DPA1, and DPB1 alleles from DNA collected from 68 T1D, 219 CD, and seven T1D w/CD patients were compared with 636 HLA‐genotyped Swedish children from the general population selected as controls.DRB4*01:03:01 allele occurred more frequently in T1D w/CD (odds ratio (OR) = 7.84; 95% confidence interval (95% CI) = , P = 0.0002) and T1D , P = 1.07 × 10−14), respectively. The DRB3*01:01:02 allele occurred more frequently in CD as compared to controls , P = 4.24 × 10−71), but less frequently in T1D , P = 7.29 × 10−07) and T1D w/CD , P ≤ 0.999). The frequency of the DRB4*01:03:01‐DRB1*04:01:01‐DQA1*03:01:01‐DQB1*03:02:01 (DR4‐DQ8) haplotype was higher in T1D w/CD  P = 3.75 × 10−9), and moderately higher in T1D  P = 0.01) compared with controls, but comparable in CD , P = 0.08) and controls.In comparison to controls, the DRB4*01:03:01, DRB3*01:01:02, and DRB3*02:02:01 of which DRB4*01:03:01 confers the strongest risk allele for developing T1D w/CD.Children with T1D and CD are associated with  HLA‐class II allele sequencing was performed using the ScisGo HLA v4 typing kit . Known haplotypes were used to phase the extended haplotypes and to predict the genotypes. Amplicon‐based 2‐stage polymerase chain reaction (PCR)‐based amplification of HLA‐class II alleles and sequencing‐by‐synthesis approach by using fluorescently labeled reversible terminator nucleotides with MiSeq v2 PE500  technology was performed as previously described.2.3χ2 tests and Fisher's exact tests (if any cell contained fewer than three observations) were used to test whether the frequencies of a given allele/haplotype differed between cases and noncases. The RPE method was used to identify the disease risk alleles, haplotypes or genotypes with the strongest predisposing or protective effects at each iteration. The selected alleles were then removed from the dataset, and the analysis was repeated until no risk or protective alleles were identified. Comparisons of DR and DQ allele frequencies were performed for both exons 2 and 3 of chromosome 6p21 by performing pairwise comparisons between all study groups and listed in order of increasing P‐value, followed by the extended haplotype and genotype frequencies. In the HLA‐DR locus, alleles of HLA‐DRB1 are in linkage disequilibrium with alleles of either HLA‐DRB3 or DRB4 or DRB5. Hence, by treating these highly dependent DR subtypes and their allelic variations as different alleles, analysis of HLA‐DRB1 and the secondary DRB3, DRB4 or DRB5 alleles by PRE method produces estimates of frequencies for all haplotypes provided that expectation numbers of corresponding haplotypes are five or more copies in both patients and control subjects. P‐values ≤.05 were considered statistically significant, and alleles with a low frequency (≤1%) were not shown in the analysis. The P‐values presented are nominal and not adjusted for multiple comparisons. Analyses were performed in R (r-project.org) version 3.6.1 and R package epiDisplay version 3.5.0.1.Allelic frequency distribution analysis of HLA‐class II genes was performed using the relative predispositional effects (RPE) analysis.33.1DRB345, ‐DRB1, ‐DQA1 and ‐DQB1 allele frequencies in children with CD compared with controls are summarized in Table S1. The allelic distributions of the disease associated DRB alleles differed significantly between all the patient groups and the controls , P = 4.24 × 10−71), DRB4*01:03:01 in 32% , P = 0.002) and DRB4*01:03:02 in only 1.4% , P = 0.021). Likewise, DRB3*02:02:01 occurred in 4.6% which was less frequent than in controls , P = 1.23 × 10−9). DRB1*03:01:01 occurred in 64% of CD children which was higher than in the controls , P = 3.82 × 10−105). The DRB1*04:01:01 allele was found in 19%  P = 1.85 × 10−7) and DRB1*04:04:01 found in 12% , P = 5.66 × 10−8). The DRB1*08:01:01 allele had a protective effect in 1% , P = 0.0005).HLA‐ls Table  and 3. ADQA1*05:01:01 occurred in 64% of the CD children , P = 3.82 × 10−105), DQA1*03:01:01 in 31% , P = 2.92 × 10−18) and DQA1*03:02:01 in 2.5% , P = 0.002). The DQB1*02:01:01 allele occurred in 54% of the CD children , P = 2.06 × 10−109) and DQB1*03:02:01 in 33% , P = 1.46 × 10−22). DQB1*04:02:01 occurred in 1% , P = 0.0001).Among the HLA‐DQA1 and DQB1 alleles, DRB3*01:01:02‐DRB1*03:01:01‐DQA1*05:01:01‐DQB1*02:01:01 (DRB3‐DR3‐DQ2.5) was found in 46% of CD children , P = 1.12 × 10−61) and DRB3*02:02:01‐DRB1*03:01:01‐DQA1*05:01:01‐DQB1*02:01:01 in 3% , P = 0.0496). On a genotype level, a total of 29 different haplotype combinations were found in CD children compared with 315 in controls. Being homozygous for DRB3*01:01:02‐DRB1*03:01:01‐DQA1*05:01:01‐DQB1*02:01:01(DR3‐DQ2.5/DR3‐DQ2.5) was the most significant genotype (43) of CD group when compared to the control group , P = 1.42 × 10−57, Data not shown).A complete list of HLA‐DRB‐DQA1‐DQB1 haplotypes is summarized in Table S4. Of these, only two haplotypes were observed more frequently in CD children compared with controls: 3.2DRB345, ‐DRB1, ‐DQA1 and ‐DQB1 allele frequencies in T1D children and controls are summarized in Table S2. Of these alleles, DRB4*01:03:01 was found in 55% of T1D children , P = 1.07 × 10−14), DRB3*01:01:02 in 34% , P = 7.29 × 10−07), DRB3*02:02:01 in 4.4%, which were less frequent compared with controls , P = 0.0003). The DRB1*04:01:01 allele was the most frequent DRB1 allele and occurred in 39% , P = 4 × 10−22), followed by DRB1*03:01:01 in 38% , P = 1.05 × 10−15), and DRB1*04:04:01 in 11% , P = 0.002). The DQA1*03:01:01 allele occurred in 52% of T1D children , P = 5.38 × 10−3) and DQA1*05:01:01 in 38% , P = 1.05 × 10−15). DQB1*03:02:01 was present in 54% , P = 1.29 × 10−35) and DQB1*02:01:01 in 37.5% , P = 4.43 × 10−17). DPB1*04:02:01 occured in 2.2%, which was less frequent compared with controls , P = 0001). In contrast, DPB1*01:01:01 was associated with increased risk , P = 0007).HLA‐DRB4*01:03:01‐DRB1*04:01:01‐DQA1*03:01:01‐DQB1*03:02:01 (DRB4‐DR4‐DQ8) was more frequently found in T1D children (11%) compared with controls , P = 0.01). On a genotype level, 20 different different haplotype combinations were identified. Among those, DRB3*01:01:02‐DRB1*03:01:01‐DQA1*05:01:01‐DQB1*02:01:01(DR3‐DQ2.5/DR3‐DQ2.5) was found in 4.4% of T1D children , P = 0.0339, Data not shown).Haplotype frequencies in T1D children are summarized in Table S5. Only 3.3DRB4*01:03:01 was the most frequent occurring allele and found in 71.4% of T1D w/CD children , P = 0.0002), in comparison to 14.3% that carried either DRB3*01:01:02 or DRB3*02:02:01(P ≤ 0.999). DRB1*04:01:01 was present in 64% of T1D w/CD , P = 1.53 × 10−06), DRB1*03:01:01 in 29% , P = 0.08). DQA1*03:01:01 was present in 57% of T1D w/CD children , P = 1.07 × 10−06) and DQA1*05:01:01 in 29% . DQB1*03:02:01 occurred in 71% of T1D w/CD children , P = 7.95 × 10−07) and DQB1*02:01:01 in 29% , P = 0.06). Haplotype distributions are listed in Table S6. Among those, only DRB4*01:03:01‐DRB1*04:01:01‐DQA1*03:01:01‐DQB1*03:02:01 occurred more frequently in T1D w/CD children compared with controls and found in 42.9% , P = 3.75 × 10−9). Four different DRB3 DRB4 DRB5‐DRB1‐DQA1‐DQB1 genotypes were found among T1D w/CD children, but there was no difference compared with controls.HLA class II alleles frequencies are summarized in Table S3. 3.4DRB3, ‐DRB4, ‐DRB5 alleles using RPE analysis (Table S1‐S2‐S3), DRB4*01:03:01 rank higher in T1D and T1D w/CD predisposition than DRB3*01:01:02, which rank higher in CD predisposition in comparison to the control group. DRB4*01:03:01 occurred in 55% of T1D children , P  = 1.59 × 10−06) and 71% of T1D w/ CD children , P = 0.003), which was higher compared with 32% of CD children. The opposite was true for DRB3*01:01:02, which was found in 60% of CD children compared with 33% of T1D children , P = 7.17 × 10−09) , P = 6.3 × 10‐06) and 64% of T1D w/CD children , P = 0.0004) compared with only 19% of CD children, whereas DRB1*03:01:01 was found in 66% of CD children compared with 37% in T1D , P = 3.28 × 10−09) and 28% of T1D w/CD , P = 0.009), respectively , P = 3.28 × 10−09) and 28% of T1D w/CD , P = 0.009), respectively. In contrast, DQB1*03:02:01 was more frequently found in T1D (54%) but not compared with CD (34%) , P = 2.36 × 10−05) compared with 71% of T1D w/CD , P = 0.007).By estimating the hierarchy of risk among all ‐DRB3*01:01:02‐DRB1*03:01:01‐DQA1*05:01:01‐DQB1*02:01:01 (DRB3‐DR3‐DQ2.5) was the most common haplotype and occurred in 45% of CD children compared with 5% in T1D (P = 5.89 × 10−18), while DRB3*01:01:02‐DRB1*03:01:01‐DQA1*03:01:01‐DQB1*02:01:01 was the most common haplotype in T1D. The DRB4*01:03:01‐DRB1*04:01:01‐DQA1*03:01:01‐DQB1*03:02:01 (DR4‐DQ8) haplotype was carried in 42% of T1D w/CD children compared with 11% in T1D , P = 0.001) and 7.8% in CD , P = 5.33 × 10−06) children  was the most frequent genotype and found in 43% of CD children compared with 4.4% in T1D , P = 7.92 × 10−11, Data not shown). In T1D, the DRB3*01:01:02‐DRB1*03:01:01‐DQA1*03:01:01‐DQB1*02:01:01/DRB4*01:03:01‐DRB1*04:01:01‐DQA1*05:01:01‐DQB1*03:02:01 (DR3‐DQ2/DR4‐DQ8) genotype was found in 38% of T1D children compared with 17% of CD children , P = 0.0002) and 28% of children with T1D w/CD . In T1D w/CD, being homozygous for DRB4*01:03:01‐DRB1*04:01:01‐DQA1*05:01:01‐DQB1*03:02:01 (DR4‐DQ8/DR4‐DQ8) was the most frequent genotype and found in 42% , P = 0.002) compared with 3.2% in CD and 10% in T1D , P = 0.04, Data not shown) children, respectively.In CD children, the 4DRB4*01:03:01, DRB3*01:01:02, and DRB3*02:02:01 alleles, were found to be associated with T1D w/CD. Of these three alleles DRB4*01:03:01 was associated with T1D only, DRB3*01:01:02 was associated with CD only, but inversely associated with T1D only. The DRB3*02:02:01 allele was associated with a low predisposition in all three groups. The novelty of the study lies in the fact that several alleles in DRB3, DRB4 and DRB5 among T1D w/CD children seem to have an extended HLA polymorphism more similar to that in children with T1D than that in children with CD.The present study aimed to fill the gap of knowledge of why some children with either T1D or CD are at an increased risk for developing both diseases (T1D w/CD) by analyzing extended HLA class II genes. The main findings were that the DRB4*01:03:01‐containing haplotypes conferred a positive association with T1D w/CD as well as T1D in comparison to DRB3*01:01:02‐containing haplotypes that were positively associated with CD. Around 50% of T1D and 70% of T1D w/CD haplotypes carry the former allele compared with 60% of CD haplotypes which carry the latter allele. Noting that all copies of chromosome 6 have a DRB1 locus, and most, but not all, have a functional second DRB locus, DRB4 was shown to be secondary for DRB1*04 haplotypes. The increase of DRB4*01:03:01 on DRB1*04:01 haplotypes in DRB1*04:01/*04:01 T1D w/CD case subjects versus DRB1*03:01/DRB1*04:01 case subjects and control subjects could reflect linkage of disequilibrium (LD) with alleles at other high‐risk loci. The analyses of the extended DRB1‐DRB3‐DRB4‐DRB5 haplotypes suggests that the risk for developing both diseases likely resembles T1D risk.Dissecting the extended DRB1‐DRB3‐DRB4‐DRB5 haplotypes, On a genotype level, differences between T1D w/CD and T1D children were found of whom T1D w/CD children were more likely to be homozygous for DR4‐DQ8/DR4‐DQ8 compared with T1D children. In line with other studies, the DR3‐DQ2 haplotype occurred in over a third of T1D children,trans, in addition to the DQ molecules encoded by alleles in cis, in linkage disequilibrium; DQA1*05, and DQB1*02, encoding the DQ2.5 molecule, and DQA1*03 and DQB1*03, encoding the DQ8 molecule.The suggested hypothesis for the increased susceptibility to CD and T1D coexistence is the putative presence of DQ heterodimers encoded by alleles in The strengths of the present study were the use of high‐resolution NGTS for extended HLA genotyping, which enabled examining the disease susceptibility between T1D w/CD and extended HLA‐DRB3, DRB4 and DRB5 alleles. The RPE analysis used to estimate the association between HLA alleles (or haplotypes) and each of the outcomes  accounts for the fact that a high frequency of a given allele “induces” a lower frequency of all other alleles, as their total must remain constant.DRB4*01:03:01 and DRB3*01:01:02 of which DRB4*01:03:01 conferred the strongest risk allele for developing T1D w/CD.In conclusion, NGTS for genetic risk profiling of children with T1D and CD showed shared risk associations with The authors have declared no conflicting interests.Table S1 RPE analysis of the estimated frequencies of HLA‐DRB3, DRB4, DRB5, DRB1, DQA1 and DQB1 alleles among celiac patients and population controls. (XLSX)Table S2 RPE analysis of the estimated frequencies of HLA‐DRB3, DRB4, DRB5, DRB1, DQA1 and DQB1 alleles among type 1 diabetes patients and population controls. (XLSX)Table S3 RPE analysis of the estimated frequencies of HLA‐DRB3, DRB4, DRB5, DRB1, DQA1 and DQB1 alleles among type 1 diabetes with celiac disease patients and population controls. (XLSX)Table S4 RPE analysis of estimated frequencies of HLA‐DRB3, DRB4, DRB5, DRB1, DQA1 and DQB1 haplotypes among celiac patients and population controls. (XLSX)Table S5 RPE analysis of estimated frequencies of HLA‐DRB3, DRB4, DRB5, DRB1, DQA1 and DQB1 haplotypes among type 1 diabetes and population controls. (XLSX)Table S6 RPE analysis of the estimated frequencies of HLA‐DRB3, DRB4, DRB5, DRB1, DQA1 and DQB1 haplotypes among type 1 diabetes with celiac disease and population controls. (XLSX)Click here for additional data file.


Kampert et al. express questions regarding (1) the measurement of pulmonary function, (2) listing of the data, (3) and a model of blood flow redistribution at peak exercise described by Harms et al. In addition, (4) they comment on the peak metabolic demand of the three conditions.p = 0.001, tidal volume sm −9.9 ± 11.3% and ffpm: −14.4 ± 13.0%, p = 0.016, inhalation time sm: +12 ± 15%, ffpm: +19 ± 16%, p < 0.001, compared to nm.Ad 1: During CPET, VE sm: −12.0 ± 12.6%, ffpm: −23.1 ± 13.6%, Ad 2: The complete results are listed in Tables 2 and 3.Ad 3: Harms et al. 1998) were cited describing possible changes in the distribution of total blood flow with additional work of breathing (e.g. higher breathing resistance) [998 were p = 0.596).Ad 4: At maximum load, the metabolic demands were similar in all three conditions. The respiratory exchange ratio (RER) did not differ between the tests (nm 1.13 ± 0.08, sm 1.15 ± 0.09, ffpm 1.13 ± 0.08, one-way ANOVA A straightforward way to get a feeling for the clear results of the study could be to personally try out the effects of sm and ffpm during exercise.


The structure of the title compound exhibits a folded conformation with the three arms all on the same side of the tertiary N atom. The crystal packing features π–π interactions. 29H26N4O6, exhibits a folded conformation with the three arms all on the same side of the tertiary N atom. The two phthalimide units make a dihedral angle of 12.18 (12)° and the dihedral angles between the benzyl plane and the phthalimide units are 68.08 (7) and 67.71 (7)°. The crystal packing features π–π interactions.The structure of the title compound, C There is also a longer centrosymmetric interaction of the nitro benzyl groups (N4/C24–C29) with a distance of 4.694 (5) Å.The crystal structure consists of centrosymmetrical dimers with off-set π–π stacking between phthalimide groups (N3/C15–C22) running along the on Fig. 2. The cenet al., 20162CH2CH2N)3 resulted in 149 entries. Similar off-set π–π stacking was seen in another compound with two phthalimide groups . 3,3′-Diphthalimidodipropylamine , 2-nitrobenzylchloride , and potassium carbonate  were heated at 433 K for one h to give the title compound. Crystals suitable for X-ray analysis were slowly grown from chloroform.The title compound was prepared by using a previously reported method (Keypour Uiso(H) = 1.2Ueq(C).Crystal data, data collection and structure refinement details are summarized in Table 110.1107/S2056989020016771/zn2003sup1.cifCrystal structure: contains datablock(s) I. DOI: Click here for additional data file.10.1107/S2056989020016771/zn2003Isup4.cdxSupporting information file. DOI: Click here for additional data file.10.1107/S2056989020016771/zn2003Isup3.cmlSupporting information file. DOI: 2052908CCDC reference:  crystallographic information; 3D view; checkCIF reportAdditional supporting information:


In the crystal structure of the title compound, molecules are linked through C—H⋯O hydrogen bonds and C—H⋯π interactions, forming chains parallel to the [010] direction. The molecular geometry in the ground state was been calculated using DFT. Additionally, frontier molecular orbital and molecular electrostatic potential map analyses were performed. 14H12ClNO, the molecules are linked through C—H⋯O hydrogen bonds and C—H⋯π interactions, forming chains parallel to the [010] direction. π–π interactions and intramolecular hydrogen bonds are also observed. The molecular geometry of the title compound in the ground state has been calculated using density functional theory at the B3LYP level with the 6–311++G basis set. Additionally, frontier molecular orbital and molecular electrostatic potential map analyses were performed.In the crystal structure of the title compound, C The molecular structure has two planar rings. The whole molecule is approximately planar, with a maximum deviation of −0.0236 (12) Å from planarity for the C8 atom of Schiff base. The title compound displays an E configuration with respect to the C8=N double bond. The dihedral angle between the two phenyl ring planes is 0.34 (9)° and the C5—C8—N1—C9 torsion angle is −179.81 (15)°. The planar molecular conformation is stabilized by the intramolecular O1—H1⋯N1 hydrogen bond, which forms an S(6) motif.The structure of the title compound (I)In the crystal, the molecules are linked by C10—H10⋯O1 hydrogen bonds Table 1, generaton Fig. 2. C—H⋯π ion Fig. 2. π–π staet al., 2016E)-2-{[(3-chlorophenyl)imino]methyl}-6-methylphenol structure. With a value of 1.271 (2) Å, the N1—C8 bond in the title compound (I)E)-(5-chloro-2-methylphenyl)iminomethyl]-4-methylphenol -iminomethyl]phenol salicylaldimine -2-[(3-chlorophenylimino)methyl]-4-methoxyphenol -[imino]methyl}benzene-1,2-diol salicylaldimine  level  and ionization potential (IP) can be defined as A = −ELUMO and IP = −EHOMO. Additionally, these values can also be used calculate the electronegativity (χ), chemical hardness (η) and chemical softness (S)  method. In Fig. 5The analysis of a three-dimensional plot of the molecular electrostatic potential (MEP) surface is a technique for mapping the electrostatic potential onto the isoelectronic density surface, providing information about the reactive sites. The surface simultaneously displays molecular size and shape and the electrostatic potential value. In the colour scheme adopted, red indicates an electron-rich region with a partial negative charge and blue an electron-deficient region with partial positive charge, light blue indicates a slightly electron-deficient region, yellow a slightly electron-rich region and green a neutral region  and 4-chloroaniline  was stirred with ethanol (30 mL) at 377 K for 4 h, affording the title compound . Single crystals suitable for X-ray measurements were obtained by recrystallization from methanol at room temperature.Uiso(H) = 1.2–1.5Ueq(C).Crystal data, data collection and structure refinement details are summarized in Table 210.1107/S2056989019017353/mw2154sup1.cifCrystal structure: contains datablock(s) I. DOI: 10.1107/S2056989019017353/mw2154Isup2.hklStructure factors: contains datablock(s) I. DOI: Click here for additional data file.10.1107/S2056989019017353/mw2154Isup3.cmlSupporting information file. DOI: 1974885CCDC reference:  crystallographic information; 3D view; checkCIF reportAdditional supporting information:


Pbca. The phenol ring is inclined to the benzonitrile ring by 25.65 (3)°. The configuration about the C=N bond is E, stabilized by a strong intramolecular O—H⋯N hydrogen bond that forms an S(6) ring motif.The title compound crystallizes in the orthorhombic space group  15H12N2O, was synthesized by condensation reaction of 2-hydroxy-5-methylbenzaldehyde and 2-aminobenzonitrile, and crystallizes in the orthorhombic space group Pbca. The phenol ring is inclined to the benzonitrile ring by 25.65 (3)°. The configuration about the C=N bond is E, stabilized by a strong intramolecular O—H⋯N hydrogen bond that forms an S(6) ring motif. In the crystal, C—H⋯O and C—H⋯N interactions lead to the formation of sheets perpendicular to the a axis. C—H⋯π interactions, forming polymeric chains along the a-axis direction, connect these sheets into a three-dimensional network. A Hirshfeld surface analysis indicates that the most important contributions for the packing arrangement are from H⋯H and C⋯H/H⋯C interactions. The density functional theory (DFT) optimized structure at the B3LYP/6–311 G level is compared with the experimentally determined molecular structure and the HOMO–LUMO energy gap is given.The title compound, C RCH=N–R′) are prepared by a condensation reaction between amines and reactive carbonyl compounds, such as aldehydes. Schiff bases are employed as catalyst carriers  and keto–amine (NH) forms. Depending on the tautomers, two types of intramolecular hydrogen bonds are generally observed in ortho-hydroxy Schiff bases, namely O—H⋯N in enol–imine and N—H⋯O in keto–amine tautomers  ring motif . The C10—O1 bond length [1.3503 (17) Å for X-ray and 1.337 Å for B3LYP] indicates single-bond character, while the imine C8=N2 bond length [1.2795 (17)Å for X-ray and 1.291 Å for B3LYP] indicates double-bond character. All bond lengths and bond angles are within normal ranges and are comparable with those in related Schiff base compounds . As shown in Fig. 5b, the most widely scattered points in the fingerprint plot are related to H⋯H contacts, which make a contribution of 39.2% to the Hirshfeld surface. There are also N⋯H/H⋯N , O⋯H/H⋯O  and C⋯C  contacts, with smaller contributions from C⋯N/N⋯C (2.6%), C⋯O/O⋯C (0.4%) and N⋯N (0.3%) contacts.In order to better visualize and analyze the role of weak intermolecular contacts in the crystal, a Hirshfeld surface (HS) analysis  calculations using the standard B3LYP functional and a 6-311G basis-set , the ionization potential (I = -ELUMO), HOMO–LUMO energy gap (ΔE), the chemical hardness (η) and softness (S) of the title compound were predicted based on the EHOMO and ELUMO energies  and the lowest-unoccupied molecular orbital (LUMO) are very important parameters for quantum chemistry. Many electronic, optical and chemical reactivity properties of compounds can be predicted from frontier molecular orbitals -2-{[(3-chlorophenyl)imino]methyl}-6-methylphenol -2-[(2-hydroxy-5-methoxybenzylidene)amino]benzonitrile -2-[(5-bromo-2-hydroxybenzylidene)amino]benzonitrile benzonitrile -2-benzonitrile -2-(4-diethylamino-2-hydroxybenzylideneamino)benzonitrile -2-[amino]benzonitrile  ring motif. The dihedral angles between the aromatic rings are generally smaller than the value of 25.65 (3)° observed for the title compound, with angles between 1.09 (4)° (for FOWXOF and GEJGAE) and 13.84 (13)° (for PUJDOO). Only YOVBUH features angles similar to those of (I)A search of the Cambridge Structural Database  in ethanol (15 ml) and 2-aminobenzonitrile  in ethanol (15 ml) and stirring the mixture for 5 h under reflux . Single crystals of the title compound suitable for X-ray analysis were obtained by slow evaporation of an ethanol solution.Uiso(H) = 1.2–1.5Ueq(C). The position of the H1 atom was obtained from a difference map; it was placed in a calculated position with a fixed C—O—H angle, but the O—H distance and the torsion angle were allowed to freely refine.Crystal data, data collection and structure refinement details are summarized in Table 310.1107/S2056989020008907/zl2787sup1.cifCrystal structure: contains datablock(s) I. DOI: 10.1107/S2056989020008907/zl2787Isup2.hklStructure factors: contains datablock(s) I. DOI: Click here for additional data file.10.1107/S2056989020008907/zl2787Isup3.cmlSupporting information file. DOI: 2013269CCDC reference:  crystallographic information; 3D view; checkCIF reportAdditional supporting information:


The structures of the four isomeric hydrogen-bonded 1:1 co-crystals of 6-methylquinoline with 2-chloro-4-nitrobenzoic acid, 2-chloro-5-nitrobenzoic acid, 3-chloro-2-nitrobenzoic acid and 4-chloro-2-nitrobenzoic acid have been determined at 185–190 K. In each crystal, the acid and base molecules are linked by a short O—H⋯N hydrogen bond. 7H4ClNO4·C10H9N, namely, 2-chloro-4-nitrobenzoic acid–6-methylquinoline (1/1), (I), 2-chloro-5-nitrobenzoic acid–6-methylquinoline (1/1), (II), 3-chloro-2-nitrobenzoic acid–6-methylquinoline (1/1), (III), and 4-chloro-2-nitrobenzoic acid–6-methylquinoline (1/1), (IV), have been determined at 185–190 K. In each compound, the acid and base molecules are linked by a short hydrogen bond between a carboxyl O atom and an N atom of the base. The O⋯N distances are 2.5452 (12), 2.6569 (13), 2.5640 (17) and 2.514 (2) Å, respectively, for compounds (I)–(IV). In the hydrogen-bonded acid–base units of (I), (III) and (IV), the H atoms are each disordered over two positions with O site:N site occupancies of 0.65 (3):0.35 (3), 0.59 (4):0.41 (4) and 0.48 (5):0.52 (5), respectively, for (I), (III) and (IV). The H atom in the hydrogen-bonded unit of (II) is located at the O-atom site. In all of the crystals of (I)–(IV), π–π interactions between the quinoline ring system and the benzene ring of the acid molecule are observed. In addition, a π–π interaction between the benzene rings of adjacent acid molecules and a C—H⋯O hydrogen bond are observed in the crystal of (I), and C—H⋯O hydrogen bonds and O⋯Cl contacts occur in the crystals of (III) and (IV). These intermolecular interactions connect the acid and base molecules, forming a layer structure parallel to the bc plane in (I), a column along the a-axis direction in (II), a layer parallel to the ab plane in (III) and a three-dimensional network in (IV). Hirshfeld surfaces for the title compounds mapped over dnorm and shape index were generated to visualize the weak intermolecular interactions.The structures of the four isomeric compounds of 6-methylquinoline with chloro- and nitro-substituted benzoic acids, C Ka values of the acids and bases as well as intermolecular interactions in the crystals. In our ongoing study on crystal structures of the system of quinoline derivatives–chloro- and nitro-substituted benzoic acids, we have shown that three compounds of quinoline with 3-chloro-2-nitrobenzoic acid, 4-chloro-2-nitrobenzoic acid and 5-chloro-2-nitrobenzoic acid, the ΔpKa [pKa(base) − pKa(acid)] values of which are 3.08, 2.93 and 3.04, respectively, have a short double-well O—H⋯N/O⋯H—N hydrogen bond between the carboxy O atom and the aromatic N atom , 8-hydroxyquinolinium 3-chloro-2-nitrobenzoate (ΔpKa = 3.02) and 3-chloro-2-nitrobenzoic acid–5-nitroquinoline (1/1) (ΔpKa = 0.98) , 5-chloro-2-nitrobenzoic acid–5-nitroquinoline (1/1) (ΔpKa = 0.94) –(IV).Properties of hydrogen bonds formed between organic acids and organic bases depend on the pThe molecular structures of compounds (I)–(IV) are shown in Fig. 1In the hydrogen-bonded acid–base unit of compound (I)Similar to (I)P212121. In the acid–base unit, the quinoline ring system and the benzene ring of the acid are slightly twisted to each other with a dihedral angle of 14.50 (5)°. The quinoline ring system and the carboxy group are also slightly twisted with a dihedral angle of 12.55 (18)°. The benzene ring makes dihedral angles of 3.14 (18) and 85.04 (11)°, respectively, with the carboxy group and the nitro group.Compound (III)Cc. In the acid–base unit, the quinoline ring system and the benzene ring of the acid are twisted to each other with a dihedral angle of 30.39 (9)°. The quinoline ring system and the carboxy group are also twisted with a dihedral angle of 21.7 (3)°. The benzene ring makes dihedral angles of 16.4 (3) and 74.4 (3)°, respectively, with the carboxy group and the nitro group.Compound (IV)i; symmetry code as given in Table 1c-axis direction  −x + 1, −y + 1, −z + 1]. The dimeric units are further linked into a column structure stacked along the b-axis direction through a weak π–π interaction between the benzene rings with Cg1⋯Cg1iv = 3.9401 (6) Å . The molecular chains are thus stacked into a layer parallel to the bc plane via these π–π interactions.In the crystal of (I)on Fig. 2. The aciit Fig. 3; the cenvia π–π interactions between the acid benzene ring and the quinoline ring system, so that the hydrogen-bonded acid–base units related by an inversion center are linked into a column structure along the a-axis direction  −x, −y + 1, −z + 1; (ii) −x + 1, −y + 1, −z + 1]. There are no significant interactions between the columns.In the crystal of (II)on Fig. 4. The ceni; symmetry code as in Table 3b-axis direction , 3.6126 (8) and 3.6393 (8) Å, respectively, for Cg1⋯Cg2iii, Cg1⋯Cg3iii and Cg1⋯Cg3iv, where Cg1, Cg2 and Cg3 are the centroids of the C1–C6, N2/C8–C11/C16 and C11–C16 rings, respectively  is observed between the layers.In the crystal of (III)on Fig. 5. The aciem Fig. 6, and thuc-axis direction  Å; (ii) x, −y, z + a-axis direction via π–π interactions between the acid ring and the quinoline ring system  x − y + z − x + y + z − In the crystal of (IV)on Fig. 7 via C—H⋯em Fig. 8, and thudnorm and shape index –(IV) mapped over et al., 2016trans-but-2-enedioic acid) –(IV) were obtained by slow evaporation from acetonitrile solutions of 6-methylquinoline with chloro-nitrobenzoic acids in a 1:1 molar ratio at room temperature [80 ml acetonitrile solution of 6-methylquinoline (0.20 g) and chloro-nitrobenzoic acid (0.28 g for each acid)].Uiso(H) = 1.5Ueq(N or O); the refined distances are given in Tables 1Uiso(H) = 1.2 or 1.5Ueq(C).Crystal data, data collection and structure refinement details are summarized in Table 510.1107/S2056989020013134/hb7946sup1.cifCrystal structure: contains datablock(s) global, I, II, III, IV. DOI: 10.1107/S2056989020013134/hb7946Isup2.hklStructure factors: contains datablock(s) I. DOI: 10.1107/S2056989020013134/hb7946IIsup3.hklStructure factors: contains datablock(s) II. DOI: 10.1107/S2056989020013134/hb7946IIIsup4.hklStructure factors: contains datablock(s) III. DOI: 10.1107/S2056989020013134/hb7946IVsup5.hklStructure factors: contains datablock(s) IV. DOI: Click here for additional data file.10.1107/S2056989020013134/hb7946Isup6.cmlSupporting information file. DOI: Click here for additional data file.10.1107/S2056989020013134/hb7946IIsup7.cmlSupporting information file. DOI: Click here for additional data file.10.1107/S2056989020013134/hb7946IIIsup8.cmlSupporting information file. DOI: Click here for additional data file.10.1107/S2056989020013134/hb7946IVsup9.cmlSupporting information file. DOI: 2034476, 2034475, 2034474, 2034473CCDC references:  crystallographic information; 3D view; checkCIF reportAdditional supporting information: