Self-Assembled Hydrogen-Bonding Chains of Copper(II) 2-Nitrobenzoate with Nicotinamide

Abstract  

The synthesis, spectral characterization and crystal structure of two new nitrobenzoatocopper(II) complexes, namely, [Cu₂(2-O₂Nbz)₄(nia)₂]·ACN (1) and [Cu₂(2-O₂Nbz)₄(ACN)₂] (2) (where 2-O₂Nbz = 2-nitrobenzoate, nia = nicotinamide and ACN = acetonitrile) are reported. The complexes 1 and 2 form dinuclear units of the paddle-wheel type around the crystallographic inversion centers. The copper ions are bridged by four 2-nitrobenzoate anions and the neutral N-donor ligands, viz. nicotinamide in 1 and acetonitrile in 2, are coordinated at apical positions. Selected geometric parameters of both complexes are compared with values for related tetra-2-nitrobenzoate complexes of copper(II) as well as the other dimeric copper(II) carboxylates with apical nicotinamide and acetonitrile ligands. The molecules of 1 are linked with N–H···O and C–H···O hydrogen bonds. The π–π stacking interactions in 1 are observed between benzene rings of 2-nitrobenzoate anions and pyridine rings of nicotinamide and also between acetonitrile molecules and benzene rings of 2-nitrobenzoate anions. The C–H···O hydrogen-bonds and CH/π interactions are observed in crystal structure of 2.     

5-Pyridine 4-yl-3H-(1,3,4) Oxadiazole-2 Thione Hydrochloride Monohydrate, (I), and 4 [5-Ethylsulfanyl)-(1,3,4) Thiadiazole-2-yl]-Pyridinium Perchlorate, (II)

Abstract  

The title compounds C₇H₈ClN₃O₂S, (I), and C₉H₁₀ClN₃O₄S_2, (II), both crystallize in monoclinic space group P2₁ /c with unit cell parameters (I) a = 7.9402(7), b = 10.6312(9), c = 11.7626(10), ?, β = 99.271(5)°, Z = 4 and (II) a = 5.1439(2), b = 9.0636(4), c = 27.1814 (7), ?, β = 95.116(2)°, Z = 4. In (I) the molecule consists of a 5-pyridine-4-yl group bonded to the carbon atom at the 5 position of (1, 3, 4) oxadiazole-2 thione hydrochloride monohydrate. The angle between the mean planes of the oxadiazole and pyridine rings is 9.6(6)°. Crystal packing in (I) is stabilized by strong N–H···O hydrogen bonds in concert with a solvent water molecule and weak O–H···Cl, O–H···S, N–H···Cl intermolecular interactions. The crystal structure of compound (II) consists of 4 [5-ethylsulfanyl)-(1, 3, 4) thiadiazole-2-yl]-pyridinium perchlorate, (C₉H₁₀N₃S₂)⁺(ClO₄)⁻, cation–anion pairs, containing strong intermolecular N–H···O hydrogen bonds and weak C–H···O and N–H···O intermolecular interactions operating between the ionic species that form a cooperative hydrogen-bonded, infinite chain O–H···O–H···O–H network which generates a sheet motif structure in the unit cell. It is also supported by weak intermolecular Cg···Cg π–π and Cl–O···Cg π-ring interactions which gives additional support to molecular packing stability in the unit cell. Geometry optimized MOPAC AM1 computational calculations on each compound provides support to the structural features in their respective crystal structures.     

Crystal Structure of 2-<Emphasis Type="Italic">Exo</Emphasis>-Phenyl-2,3,4,5-Tetrahydro-1,4-Epoxinafto[1,2-b]azepine

Abstract  

The title compound, C₂₀H₁₇NO, crystallizes in the orthorhombic P2₁2₁2₁ space group with unit cell parameters a = 7.6903(7) ?, b = 18.979(2) ?, c = 19.753(2) ?, with two crystallographically independent molecules in the asymmetric unit, which differ from one another in the slight rotation of the phenyl ring; this allows the formation of three internal hydrogen bonds, two of the type C–H···N and one of the type C–H···O, in one of the molecules, in contrast with only two of the type C–H···N in the other. The compound is rich in aromatic π rings and therefore the crystal packing is entirely dominated by cohesive weak C–H···π interactions among neighboring molecules producing an efficient packing with 71.2% of occupied space.     

Structural Studies of Two Isoelectronic Tetrakis Isocyano Complexes

Abstract  

Two isoelectronic tetrakis isocyano compounds, tetra(p-isocyanoanisole)nickel(0) and tetra(p-isocyanoanisole)copper(I) hexafluorophosphate were synthesized from nickel bis cyclooctadiene and copper (I) tetra acetonitrile hexafluorophosphate and the isonitrile, respectively, and their structures were determined. The nickel complex crystallizes in the orthorhombic space group P2₁2₁2₁ with a = 9.6709(8), b = 15.2324(13), c = 19.0955(16) ? and Z = 4. The copper salt forms crystals with a tetragonal setting in P4/n with a = b = 15.8206(5), c = 6.5848(4) ? and Z = 2. Both complexes exhibit the approximate tetrahedral coordination environment expected for 18 valence electron complexes with soft σ-donor π-acceptor ligands. Packing in the nickel complex is dominated by weak π–π stacking, C–H···π_phenyl, and C–H···π interactions towards the isonitrile carbon and nitrogen atoms, and several slightly stronger C–H···O interactions. In the copper complex the presence of the PF₆ anion allows for the formation of stronger C–H···F interactions, and these in combination with π–π stacking and C–H···O hydrogen bonds dominate the packing.     

Syntheses and Crystal Structures of Two Ferrocenyl Dicarboximides

Abstract  

Reactions of 1,1′-ferrocenedicarboxylic chloride with 2-aminopyrimidine and 2-aminopyrazine produce organometallic dicarboximides I and II, respectively. They crystallize in space groups F dd2 and P2₁/c, respectively. The molecules of I lying on twofold rotation axes are linked into a B-faced sheet by a C–H···O=C hydrogen bond [H····O = 2.46, C···O = 3.163(7) ? and C–H···O = 132°]. The sheets are linked into a layered structure by two types of weak C–H···O=C hydrogen bonds [H···O = 2.71, C···O = 3.340(8) ? and C–H···O = 126°; H···O = 2.69, C···O = 3.303(10) ? and C–H···O = 124°]. The molecules of II are linked into a centrosymmetric R ₂²(12) dimer by a C–H···O hydrogen bond [H···O = 2.40, C···O = 3.321(10) ? and C–H···O = 172°]. The dimers are further packed along the a axis by a C–H···O hydrogen bond [H···O = 2.69, C···O = 3.416(9) ? and C–H···O = 135°] to give an [100] double-chain. The double-chain is packed in the [010] direction by a C–H···O=C hydrogen bond [H···O = 2.69, C···O = 3.532(9) ? and C–H···O = 150°]. Further the intermolecular C–H···N hydrogen bond involving the cyclopentadienyl group as a hydrogen-bond donor and pyrazine N atom as an acceptor [H···O = 2.71, C···N = 3.536(10) ? and C–H···N = 148°] leads to a three-dimensional framework structure.     

Inter- and Intra-Molecular Hydrogen Bonding in Bis(2-amino-5-fluoro-3-methylphenyl)disulfide

Abstract  Bis(2-amino-5-fluoro-3-methylphenyl)disulfide was obtained by oxidation of 2-amino-5-fluoro-3-methylbenzenethiol and was characterized by elemental analysis, IR and ¹H-NMR spectroscopy. The X-ray structure was determined. Crystal data: C₁₄H₁₄N₂F₂S₂: Monoclinic, P2₁ /n, a = 11.8268(3), b = 9.5770(3), c = 12.3977(3) ?, β = 98.079(2)°, V = 1390.29(7) ?, Z = 4. The supramolecular structure arises because the NH₂ groups form three center S···H···F hydrogen bonds and two center N–H···F and N–H···S hydrogen bonds. Index Abstract  Inter- and Intra-Molecular Hydrogen Bonding in Bis(2-amino-5-fluoro-3-methylphenyl)disulfide J. E. Drake¹, M. B. Hursthouse², M. E. Light², R. Maheshwari³, K.G. Ojha³, R. Ratnani^3* Bis(2-amino-5-fluoro-3-methylphenyl)disulfide is linked into a three-dimensional frame work by a combination of intermolecular N–H···F and N–H···N and intramolecular N–H···S hydrogen bonds. The supramolecular structure arises because the NH₂ groups form three center S···H···F hydrogen bonds and two center N–H···F and N–H···S hydrogen bonds.      

Hydrogen Bonded 3D Supramolecular Architectures of Two Organic Salts Assembled from 2-Aminoheterocyclic Compounds and Phosphoric Acid

Abstract  

Two phosphate salts (2-aminopyrimidine): (phosphoric acid): H₂O [HL1⁺ (H₂PO₄) ⁻ ]·H₂O (1), and (4-phenylthiazol-2-amine): (phosphoric acid) [HL2⁺·(H₂PO₄)⁻] (2) based on 2-aminoheterocyclic compounds, 2-aminopyrimidine (L1), and 4-phenylthiazol-2-amine (L2) were prepared and structurally characterized by X-ray crystallography. Compound 1 crystallizes in the triclinic, space group P-1, with a = 6.2201(7) Å, b = 8.6139(9) Å, c = 9.4800(10) Å, α = 109.685(2)°, β = 106.3340(10)°, γ = 95.4450(10)°, V = 448.72(8) Å³, Z = 2. For 1, the cations were linked to each other via intermolecular C–H···N hydrogen bonds to form a 1-D chain structure running along the a-axis direction. The anions and the water molecules were connected alternatively along the a-axis direction through O–H···O hydrogen bonds to form a 1-D chain also. The cationic chains and the anionic chains were alternatively connected along the c-axis direction through N–H···O and C–H···O hydrogen bonds to form a 2D corrugated sheet. Adjacent sheets were combined together through π–π interaction to form double sheet. These double sheets were further joined together by O–H···O and N–H···O hydrogen bonds to produce a 3D network structure. Compound 2 crystallizes in the Orthorhombic, space group Pbca, with a = 10.1929(10) Å, b = 8.4406(9) Å, c = 27.589(2) Å, α = 90°, β = 90°, γ = 90°, V = 2373.6(4) Å³, Z = 8. In 2, the phosphates formed 1D chain along the b-axis through two P–O–H···O = P hydrogen bonds. The cations formed 1D zigzag chain along the b-axis direction under the CH–π interaction. The anionic chains were intercalated between two adjacent cationic chains through N–H···O, O–H···O, C–H···O, and O–S contacts. Such stacking repeated along the c-axis direction to form a 3D network structure.     

Synthesis and Crystal Structure of a New Ion-Pair Complex Based on [Ni(tdas)<Subscript>2</Subscript>]<Superscript>2−</Superscript> Anion and Triphenylphosphinium Cation

Abstract  A new ion-pair complex, bis(1-benzyltriphenylphosphinium) bis(1,2,5-thiadiazole-3,4-dithiolato)nickelate(II), [BzTPP]₂[Ni(tdas)₂](1), has been prepared and characterized by elemental analyses, UV, IR, MS spectrum, molar conductivity and single crystal X-ray diffraction. The title complex crystallizes in the triclinic space group P-1, a = 9.098(1) Å, b = 9.666(1) Å, c = 29.573(3) Å, α = 83.81(1)°, β = 81.97(1)°, γ = 78.83(1)°, V = 2,517.5(4) ų, Z = 2. The unit cell contains two [BzTPP]⁺ and two halves of [Ni(tdas)₂]²⁻ anions in which the anion exhibits a quasi-planar structure. The [BzTPP]⁺ cation adopts a conformation where four phenyl rings are twisted to the C–C–P reference plane. The weak cation–cation C–H···π, π···π interactions and anion–cation C–H···N hydrogen bonds between the anion and cation play an important role in the stacking and stabilizing of the title complex. Graphical Abstract  The title new ion-pair complex, bis(1-benzyltriphenylphosphinium) bis(1,2,5-thiadiazole-3,4-dithiolato)nickelate(II), [BzTPP]₂[Ni(tdas)₂](1), contains two [BzTPP]⁺ and two halves of [Ni(tdas)₂]²⁻ anions in which the weak cation–cation C–H···π, π···π interactions and anion−cation C–H···N hydrogen bonds between the anion and cation play an important role in the stacking and stabilizing of the title complex.      

Near Supramolecular Isomorphism Involving Homologous Solvents: Pyrimethaminium Terephthalate Methanol Solvate and Pyrimethaminium Terephthalate Ethanol Solvate

Abstract  

Two nearly isostructural pseudopolymorphic forms of pyrimethaminium terephthalate have been synthesized and their supramolecular architectures analyzed. In both the crystals, the protonated pyrimethamine (PMN) cation interacts with the carboxylate anion via N–H···O hydrogen bonds to form the robust R₂²(8) motif. The centrosymmetrically (N–H···N) paired PMN cations are bridged on either sides by interaction of the solvent molecules with the amino groups (N–H···O) of PMN cations. The combination of two R₂²(8) motifs formed between the PMN cations and PMN cation solvent, leads to the formation of the complementary DADA (D = hydrogen bonded donor, A = hydrogen bonded acceptor) array of quadruple hydrogen bonds. The solvent molecule further interacts with the corresponding anion via O–H···O hydrogen bonds. Moreover, both the solvates exhibit several edge to face stacking interactions. They have in common, two C–H···π interactions; one between the symmetry related cations and other between the cation and anion. The molecular packing of the ethanol solvate is further strengthened by C–H···O and C–H···π interaction between the solvent and the ions.     

Synthesis and Crystal Structure of (2S,6R) Ethyl 1,2,6-triphenyl-4-(phenylamino)-1,2,5,6-tetrahydropyridine-3-carboxylate

Abstract  

The title compound, (2S,6R), Ethyl 1,2,6-triphenyl-4-(phenylamino)-1,2,5,6-tetrahydropyridine-3-carboxylate (C₃₂H₃₀N₂O₂), was synthesised by the reaction of benzaldehyde, aniline and ethylacetoacetate, in the presence of l (−) proline–Fe(III) complex, formed in situ, at room temperature. The compound was characterized by spectral methods and X-ray diffraction studies. The compound crystallizes in the triclinic space group P − 1 with the following unit-cell parameters: a = 9.651(4), b = 10.909(5), c = 13.737(7) ?, α = 106.597(7), β = 108.664(8), γ = 99.779(6)°, Z = 2. The crystal structure was solved by direct methods using single-crystal X-ray diffraction data collected at 100 K and refined by full-matrix least-squares procedures to a final R-value of 0.0633 for 3415 observed reflections. The 1,2,5,6-tetrahydropyridine ring exhibits a flat boat conformation. The structure has intra- and intermolecular hydrogen bonds of the type N–H···O, C–H···O and C–H···π, which help to stabilize the crystal structure.     

Synthesis and Crystal Structure of a Fe(III) Complex with an Isonicotinyl Hydrazone Ligand, [Fe(N-Isonicotinamidosalicylaldimine)Cl<Subscript>2</Subscript>]

Abstract  

A new complex [Fe(N-isonicotinamidosalicylaldimine)Cl₂] has been synthesized by template reaction at room temperature and structurally characterized by X-ray single-crystal analysis. The complex crystallizes in triclinic crystal system, Pī space group, a = 7.273(6) ?, b = 10.015(8) ?, c = 10.479(8) ?, α = 71.067(10)°, β = 89.964(11)°, γ = 75.528(10)°, V = 696.4(9) ?³ and Z = 2. The coordination geometry around the Fe(III) ion is a distorted trigonal bipyramid with a O₂N₁Cl₂ donor set. In the crystal structure, N–H···Cl, C–H···O and C–H···Cl hydrogen bonds and π···π stacking interactions involving aromatic and unclosed π-systems link the molecules to form supramolecular double layers.     

Supramolecular Aggregation in the 1:1 Co-crystal Formed Between Merocyanine Dye and 3-Nitrophenol,Characterized as a Hydrate

Abstract  The title organic salt comprises a (E)-4-[2-(4-hydroxyphenyl)vinyl]-1-methylpyridinium cation, a 3-nitro-phenoxide anion and a solvent water molecule of crystallisation. The anions and water molecules aggregate to form supramolecular chains facilitated by charge-assisted O–H···O hydrogen bonds and these form layers which are interspersed by layers of cations. Interactions between layers include O–H···O hydrogen bonding, as well as C–H···O and C–H···π contacts; π···π and C–H···O contacts are found within layers of cations. The compound crystallizes in the monoclinic space group P2₁/n with a = 15.018(7) ?, b = 7.328(2) ?, c = 17.571(7) ?, β = 112.342(15)°, and Z = 4. Index Abstract  A layer structure comprising alternating anions/water molecules and cations associated via charge-assisted O–H···O hydrogen bonding as well as C–H···O, C–H···π and π···π contacts is found in (II) .     

Synthesis and X-Ray Crystallographic Analysis of 2-(2, 4-Dimethyl Pyrrolyl) Benzothiazole

Abstract  

Synthesis of 2- (2, 4-dimethyl pyrrolyl) benzothiazole by chemical means and molecular structure by X-ray crystallographic techniques is reported. The compound crystallizes in the orthorhombic crystal system with space group Pbca and unit cell parameters: a = 12.161(9), b = 0.787(1), c = 16.792(2) Ǻ, V = 2202.8(4) Ǻ³ and Z = 8. The final reliability index is 0.073 for 7,959 observed reflections. The benzothiazole and pyrrole rings exist in planar conformations. The dihedral angle between the least-squares planes of both these moieties is 13.31°. There exists an isolated C4–H4···N1 intermolecular interaction, besides two C–H···S and C–H···N intermolecular interactions. The presence of C–H···S and C–H···N intramolecular interactions make the present molecule look like a virtual two-six-membered and three-five-membered ring structure.     

Synthesis and Crystal Structure of Tetrabutylammonium 4-(2-Bromothiophene-5-Sulfanilamide)-Benzoate

Abstract  

Tetrabutylammonium 4-(2-bromothiophene-5-sulfanilamide)-benzoate crystallizes in C_2/C lattice with a = 18.3389(17), b = 16.540(16), c = 15.8280(15) ?, β = 116.959(2), V = 4279.5(7) ?³, Z = 4, and R = 0.0560. In the structure a very short centrosymmetric hydrogen bond and C=O···Br halogen bond interactions, together with N–H···O and C–H···O hydrogen bonds give a three-dimensional network.     

Structures of two N-{2-([(5-amino-1,3,4-thiadiazol-2-yl)difluoromethyl]-4-halophenyl}acetamides

Abstract  

The compounds, N-{2-[(5-amino-1,3,4-thiadiazol-2-yl)difluoromethyl]-4-chlorophenyl}acetamide (1: X = Cl) and N-{2([(5-amino-1,3,4-thiadiazol-2-yl)difluoromethyl]-4-bromo-phenyl}acetamide (1: X = Br), are isostructural. The molecules are near ‘‘V’’ shaped with the angles between the two aromatic planes ca. 84° in each case. The various intermolecular interactions, namely N–H···O, N–H···N, N–H···F, and C–H···N hydrogen bonds and C–H···π, C–Cl···π and C–O···π interactions, generate 3-D arrays. Compound (1: X = Cl) crystallizes in the monoclinic space group P21/c with a = 16.9032(7) ?, 10.2193(4) ?, c = 7.5227(4) ?, β = 100.179(3)° and Z = 4. Compound (1: X = Br) crystallizes in the monoclinic space group P21/c with a = 17.2119(4) ?, 10.2167(2) ?, c = 7.5677(2) ?, β = 100.326(2)° and Z = 4.     

Synthesis,Crystal Structure and Antibacterial Activity of 5-Bromonicotinic Acid [1-(4-Chlorophenyl)methylidene]hydrazide Monohydrate Methanol Solvate

Abstract  The compound 5-bromonicotinic acid [1-(4-chlorophenyl)methylidene]hydrazide monohydrate methanol solvate, derived from the condensation reaction of 5-bromonicotinic acid hydrazide with 4-chlorobenzaldehyde in a methanol solution, was synthesized and characterized by elemental analysis, IR spectrum, ¹H NMR and X-ray single crystal determination. The compound crystallizes in the triclinic space group P − 1 with unit cell dimensions a = 6.9360(14) ?, b = 10.070(2) ?, c = 12.267(3) ?, α = 84.39(3)°, β = 86.10(3)°, γ = 80.50(3)°, V = 839.8(3) Ǻ³, Z = 2, R ₁ = 0.0724, and wR ₂ = 0.1720. X-ray structure determination reveals that the compound has a trans configuration with respect to the C=N double bond or C–N single bond. In the crystal structure, molecules are linked through intermolecular O–H···N, O–H···O, and C–H···O hydrogen bonds, forming layers parallel to the ab plane. The preliminary biological tests show that the compound has excellent antibacterial activity. Index Abstract  The compound 5-bromonicotinic acid [1-(4-chlorophenyl)methylidene]hydrazide monohydrate methanol solvate, derived from the condensation reaction of 5-bromonicotinic acid hydrazide with 4-chlorobenzaldehyde in a methanol solution, was synthesized and characterized by elemental analysis, IR spectrum, ¹H NMR and X-ray single crystal determination. The molecule of the compound has a trans configuration with respect to the C=N double bond or C–N single bond. In the crystal structure, molecules are linked through intermolecular O–H···N, O–H···O, and C–H···O hydrogen bonds, forming layers parallel to the ab plane. The preliminary biological tests show that the compound has excellent antibacterial activity.      

Crystal Structure and Spectroscopic Properties of <Emphasis Type="Italic">trans</Emphasis>-Dibromobis(1,2-ethanediamine)chromium(III) Perchlorate

Abstract  

The crystal structure of trans-[Cr(en)₂Br₂]ClO₄ (en = 1,2-ethanediamine) has been determined by a single-crystal X-ray diffraction study at 150 K. The complex crystallizes in the space group P[`1] P\overline{1} of the triclinic system with two mononuclear formula units in a cell of dimensions a = 6.853(4), b = 8.109(5), c = 12.475(8) ?, α = 81.006(10)°, β = 77.005(10)° and γ = 74.981(10)°. The Cr atom is in a slightly distorted octahedral environment, coordinated by four nitrogen atoms of two en ligands and two bromine atoms in trans axial positions. The mean Cr–N(en) and Cr–Br bond lengths are 2.079(3) and 2.4743(10)?, respectively. The five-membered rings are in stable gauche conformations with N1–Cr1–N2 and N3–Cr2–N4 angles of 82.81(11)° and 83.67(11)°, respectively. The crystal packing is stabilized by a network of N–H···O and N–H···Br hydrogen bonds. The infrared and electronic absorption spectra are consistent with the results of X-ray crystallography.     

The Crystal Structure of 1-[2-(furan-2-yl)-6-methyl-1,2,3,4-tetrahydroquinolin-4-yl]Pyrrolidin-2-one

Abstract  

The title compound, C₁₈H₂₀N₂O₂, a potential pharmaceutical agent, crystallizes in the monoclinic P2₁/n space group with unit cell parameters a = 11.157 (7) ?, b = 8.776 (6) ?, c = 16.460 (11) ?, β = 103.08 (3)°. The tetrahydroquinoline ring system formed by the fusion of the benzene ring and the piperidine ring via two carbon atoms is coplanar, with the later adopting a sofa conformation. The pyrrolidine group in position 4 adopts an envelope conformation. Dimers related by inversion centers and linked by hydrogen bonds of the type N–H···O form cycles described by the graph set R₂²(16). Additionally, the dimers connect through weak hydrogen bonds of the type C–H···O with graph set C(10) to form chains extending along [001].     

Crystal Structure of <Emphasis Type="Italic">N</Emphasis>-(2-Pyridylmethylene)benzene-1,4-diamine

Abstract  

The crystal structure of amino containing Schiff base, N-(2-pyridylmethylene)benzene-1,4-diamine, was determined via X-ray diffraction analysis. The title compound crystallizes in orthorhombic system, space group Pc2 ₁ n, with unit cell dimensions a = 5.8945(6), b = 11.9233 (10), c = 14.5356 (16) ?, V = 1021.59 (18) ?³, Z = 4. The molecules are linked by intermolecular N–H···N hydrogen bonds to form supramolecular sheets along with the bc crystallographic plane. The crystal structure is further stabilized by C–H···π stacking interactions.     

Ordering of the Water Molecule in the Crystal Structure of 2-[3-Methyl-4-(2,2,2-Trifluoroethoxy)-2-Pyridinyl]Methylthio-<Emphasis Type="Italic">1H</Emphasis>-Benzimidazole Hydrate (Lansoprazole Sulphide Hydrate)

Abstract  

Lansoprazole sulphide (2-[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridinyl]methylthio-1H-benzimidazole) hydrate crystallizes in the triclinic space group P-1 with two molecules in the asymmetric part of the unit cell. The molecules are almost identical, the normal probability plots show that the differences between them are of statistical nature. The crystal structure is determined mainly by the O–H···N and N–H···O hydrogen bonds; and both symmetry independent molecules create the hydrogen-bonded structures on their own. The common motif is the C₂²(6) chain of molecules along x (A) or y (B), but the interactions between the chains are different: chains of molecules A are joined by O–H···N(pyridine) hydrogen bonds while those of molecules B– by relatively strong O–H···S hydrogen bonds. Additionally, in both cases there are also C–H···S, C–H···π and π–π interactions between the neighbouring molecules. The different intermolecular interactions might be connected with the observed disorder of water molecules in the B-chains. At room temperature the s.o.f.’s of two alternative positions refined at 0.760(17) and 0.240(17). The less-occupied water molecule does not take part in the O–H···S hydrogen bonding. When temperature decreases the importance of this interaction grows, the occupancy of less occupied position becomes smaller and finally, around 150 K the structure becomes fully ordered.