2′‐(4‐Fluoro­phenyl)‐[1,2,3]­triazolo[4′,5′:16,17]­androst‐5‐en‐3β‐ol methanol hemisolvate

The asymmetric unit of the title compound, C₂₅H₃₀FN₃O·0.5CH₃OH, contains four symmetry‐independent steroid and two methanol mol­ecules. The conformations of the independent steroid mol­ecules are very similar. Intermolecular O—H⋯O hydrogen bonds create two independent chains, each of which links two of the independent steroid mol­ecules plus one methanol mol­ecule via a co‐operative O—H⋯O—H⋯O—H pattern. Intermolecular C—H⋯O and C—H⋯F interactions are also observed.     

Supramolecular structures of three isomeric 4‐(methyl­phenylamino)­pyridine‐3‐sulfonamides

The structures of the three title isomers, namely 4‐(2‐methyl­anilino)pyridine‐3‐sulfonamide, (I), 4‐(3‐methyl­anilino)pyridine‐3‐sulfonamide, (II), and 4‐(4‐methyl­anilino)pyridine‐3‐sulfonamide, (III), all C₁₂H₁₃N₃O₂S, differ in their hydrogen‐bonding arrangements. In all three mol­ecules, the conformation of the 4‐amino­pyridine‐3‐sulfon­amide moiety is conserved by an intra­molecular N—H⋯O hydrogen bond and a C—H⋯O inter­action. In the supra­mol­ecular structures of all three isomers, similar C(6) chains are formed via inter­molecular N—H⋯N hydrogen bonds. N—H⋯O hydrogen bonds lead to C(4) chains in (I), and to R₂²(8) centrosymmetric dimers in (II) and (III). In each isomer, the overall effect of all hydrogen bonds is to form layer structures.     

Hydro­gen‐bonded supramolecular motifs in 4,4′‐bipyridinium 8‐hydroxy‐7‐iodo­quinoline‐5‐sulfonate dihydrate

In the title compound, C₁₀H₉N₂⁺·C₉H₅INO₄S⁻·2H₂O, the 4,4′‐bi­pyridine mol­ecule is protonated at one of the pyridine N atoms. These moieties self‐assemble into a supramolecular chain along the a axis through N—H⋯N hydrogen bonds. The quinolinol OH group acts as a donor with respect to a sulfonate O atom [O—H⋯O(sulfonate)] and acts as an acceptor with respect to a C—H group of ferron [C—H⋯O(hydroxy)], forming a supramolecular chain along the b axis. These two types of supramolecular chains (one type made up of bi­pyridine motifs and the other made up of sulfoxine motifs) interact viaπ–π stacking, generating a three‐dimensional framework. These chains are further crosslinked by C—­H⋯O hydrogen bonds and O—H⋯O hydrogen bonds involving water mol­ecules.     

Ethyl N‐[2‐(hydroxy­acetyl)­phenyl]­carbamate,ethyl N‐[2‐(hydroxy­acetyl)‐4‐iodo­phenyl]­carbamate and ethyl N‐[2‐(hydroxy­acetyl)‐4‐methyl­phenyl]­carbamate

In ethyl N‐[2‐(hydroxy­acetyl)phenyl]carbamate, C₁₁H₁₃NO₄, all of the non‐H atoms lie on a mirror plane in the space group Pnma; the mol­ecules are linked into simple chains by a single C—H⋯O hydrogen bond. The mol­ecules of ethyl N‐[2‐(hydroxy­acetyl)‐4‐iodo­phenyl]carbamate, C₁₁H₁₂INO₄, are linked into sheets by a combination of O—H⋯I and C—H⋯O hydrogen bonds and a dipolar I⋯O contact. Ethyl N‐­[2‐(hydroxy­acetyl)‐4‐methyl­phenyl]carbamate, C₁₂H₁₅NO₄, crystallizes with Z′ = 2 in the space group P; pairs of mol­ecules are weakly linked by an O—H⋯O hydrogen bond and these aggregates are linked into chains by two independent aromatic π–π stacking inter­actions.     

2‐Amino‐5‐nitro­thia­zole monoethanol solvate: triply‐interwoven hydrogen‐bonded sheets containing centrosymmetric R(8) and R(38) rings

2‐Amino‐5‐nitro­thia­zole crystallizes from solution in ethanol as a monosolvate, C₃H₃N₃O₂S·C₂H₆O, in which the thia­zole component has a strongly polarized molecular–electronic structure. The thia­zole mol­ecules are linked into centrosymmetric dimers by paired N—H⋯N hydrogen bonds [H⋯N = 2.09 Å, N⋯N = 2.960 (6) Å and N—H⋯N = 169°], and these dimers are linked by the ethanol mol­ecules, via a two‐centred N—H⋯O hydrogen bond [H⋯O = 1.98 Å, N⋯O = 2.838 (5) Å and N—H⋯O = 164°] and a planar asymmetric three‐centred O—H⋯(O)₂ hydrogen bond [H⋯O = 2.07 and 2.53 Å, O⋯O = 2.900 (5) and 3.188 (5) Å, O—H⋯O = 169 and 136°, and O⋯H⋯O = 55°], into sheets built from alternating (8) and (38) rings. These sheets are triply interwoven.     

N,N′‐Bis(2‐pyridylmeth­yl)ferrocene‐1,1′‐diyldicarboxamide and N,N′‐bis­(3‐pyridylmeth­yl)ferrocene‐1,1′‐diyldicarboxamide

The mol­ecules of N,N′‐bis­(2‐pyridylmeth­yl)ferrocene‐1,1′‐diyl­dicarboxamide, [Fe(C₁₂H₁₁N₂O)₂], contain intra­molecular N—H⋯N hydrogen bonds and are linked into sheets by three independent C—H⋯O hydrogen bonds. The mol­ecules of the isomeric compound N,N′‐bis­(3‐pyridylmeth­yl)ferrocene‐1,1′‐diyldicarboxamide lie across inversion centres, and the mol­ecules are linked into sheets by a combination of N—H⋯N hydrogen bonds and π–π stacking inter­actions between pyridyl groups.     

trans‐Di­aqua­bis(5‐carboxy‐1H‐imidazole‐4‐carboxyl­ato‐κ2N3,O4)­cobalt(II) 4,4′‐bi­pyridine solvate

In the title compound, [Co(C₅H₃N₂O₄)₂(H₂O)₂]·C₁₀H₈N₂, the Co atom is trans‐coordinated by two pairs of N and O atoms from two monoanionic 4,5‐di­carboxy­imidazole ligands, and by two O atoms from two coordinated water mol­ecules, in a distorted octahedral geometry. The 4,4′‐bi­pyridine solvent molecule is not involved in coordination but is linked by an N—H⋯N hydrogen bond to the neutral [Co(C₅H₃N₂O₄)₂(H₂O)₂] mol­ecule. Both mol­ecules are located on inversion centers. The crystal packing is stabilized by N—H⋯N and O—H⋯O hydrogen bonds, which produce a three‐dimensional hydrogen‐bonded network. Offset π–π stacking interactions between the pyridine rings of adjacent 4,4′‐bi­pyridine molecules were observed, with a face‐to‐face distance of 3.345 (1) Å.     

Tris(1H‐benzimidazol‐2‐yl­meth­yl)­amine–solvent adducts

The tris­(1H‐benzimidazol‐2‐yl­meth­yl)­amine (ntb) mol­ecule crystallizes in different solvent systems, resulting in two kinds of adduct, namely the monohydrate, C₂₄H₂₁N₇·H₂O or ntb·H₂O, (I), and the acetonitrile–methanol–water (1/0.5/1.5) solvate, C₂₄H₂₁N₇·C₂H₃N·0.5CH₄O·1.5H₂O or ntb·1.5H₂O·0.5MeOH·MeCN, (II). In both cases, ntb adopts a tripodal mode to form hydrogen bonds with a solvent water mol­ecule via two N—H⋯O and one O—H⋯N hydrogen bond. In (I), the ntb·H₂O adduct is further assembled into a two‐dimensional network by N—H⋯N and O—H⋯N hydrogen bonds, while in (II), a double‐stranded one‐dimensional chain structure is assembled via N—H⋯O and O—H⋯O hydrogen bonds, with the acetonitrile mol­ecules located inside the cavities of the chain structure.     

Naphthalene‐1,7‐diol

The asymmetric unit of the title compound, C₁₀H₈O₂, contains two planar symmetry‐independent mol­ecules linked by an O—H⋯O hydrogen bond. In the crystal structure, mol­ecules are linked into infinite chains of rings, formed by a combination of O—H⋯O and C—H⋯O hydrogen bonds, and additionally reinforced by π–π stacking inter­actions. Adjacent chains are connected by weak C—H⋯π inter­actions.     

Bis(μ‐1,10‐phenanthrolin‐2‐olato‐κ3N,N′:O)­dicopper(I)(Cu—Cu) monohydrate

The crystal structure of the title compound, [Cu₂(C₁₂H₇­N₂O)₂]·H₂O, shows that this dinuclear complex has shorter Cu—N, Cu—O and Cu—Cu distances within the coordination sphere than similar reported complexes. The complex mol­ecule is located on a centre of symmetry and the water mol­ecule is on a twofold axis of the space group C2/c. The discrete complex mol­ecules are extended into a two‐dimensional supramolecular array viaπ–π stacking interactions, intermolecular Cu⋯Cu interactions and C—H⋯O hydrogen bonds.     

6‐(2‐Chloro­acetamido)­hexa­noic acid

Crystals of the title compound, C₈H₁₄ClNO₃, belong to the space group Cc and are characterized by an asymmetric unit containing two mol­ecules, both with a twisted conformation. The mol­ecular packing is stabilized by N—H⋯O=C hydrogen bonds between the amide groups of mol­ecules with the same conformation. In addition, hydrogen‐bonded cyclic carboxylic acid dimers are established between mol­ecules with a different conformation. The ClCH₂—CONH bond has a cis conformation in order to favour an intra­molecular Cl⋯HN electrostatic inter­action. Weak intra‐ and inter­molecular CH₂⋯O=C inter­actions are also present.     

Hydrogen‐bonded 1:1 adduct of 1,1′‐(p‐phenylene)dipyridin‐4(1H)‐one with terephthalic acid

Cocrystallization of 1,1′‐(p‐phenylene)dipyridin‐4(1H)‐one (4,4′‐dpy) and terephthalic acid (tpa) affords the hydrogen‐bonded 1:1 title complex, C₁₆H₁₂N₂O₂·C₈H₆O₄. Both mol­ecules are symmetrically disposed about independent symmetry centers. Strong O—H⋯O hydrogen bonds between tpa carboxyl groups and 4,4′‐dpy carbonyl groups produce one‐dimensional zigzag infinite chains. Each chain is linked to four surrounding chains via weak C—H⋯O inter­actions, resulting in a three‐dimensional mol­ecular framework.     

Bis(3‐amino­pyridine‐κN)(4,4′‐di­methyl‐2,2′‐bipyridine‐κ2N,N′)(per­chlorato‐κO)copper(II) per­chlorate

The title compound, [Cu(ClO₄)(C₅H₆N₂)₂(C₁₂H₁₂N₂)]ClO₄, was prepared by in situ partial ligand substitution between 3‐amino­pyridine and 4,4′‐dimethyl‐2,2′‐bipyridine at room temperature. The central copper(II) ion is five‐coordinated by one bidentate 4,4′‐dimethyl‐2,2′‐bipyridine mol­ecule, two monodentate pyridine‐coordinated 3‐amino­pyridine mol­ecules and one apical O atom from the perchlorate counter‐ion. Inter­molecular N—H⋯O and C—H⋯O hydrogen‐bonding inter­actions form a hydrogen‐bond‐sustained network.     

Displaced π–π stacking and hydrogen bonds in 3‐bromo‐N‐(2‐hydroxy‐1,1‐di­methyl­ethyl)­benz­amide

The mol­ecules of the title compound, C₁₁H₁₄BrNO₂, are assembled into a two‐dimensional network by a combination of hydrogen bonds and stacking interactions. The phenyl rings are stacked along the c direction by displaced π–π interactions, forming a lipophilic layer. The aliphatic amide residues are interconnected along [100] by O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds, forming hydro­philic layers.     

Three isomeric forms of hydroxyphenyl‐2‐oxazoline: 2‐(2‐hydroxyphenyl)‐2‐oxazoline, 2‐(3‐hydroxyphenyl)‐2‐oxazoline and 2‐(4‐hydroxyphenyl)‐2‐oxazoline

Crystal structures are reported for three isomeric compounds, namely 2‐(2‐hydroxy­phenyl)‐2‐oxazoline, (I), 2‐(3‐hydroxy­phenyl)‐2‐oxazoline, (II), and 2‐(4‐hydroxy­phenyl)‐2‐oxazoline, (III), all C₉H₉NO₂ [systematic names: 2‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (I), 3‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (II), and 4‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (III)]. In these compounds, the deviation from coplanarity of the oxazoline and benzene rings is dependent on the position of the hydroxy group on the benzene ring. The coplanar arrangement in (I) is stabilized by a strong intra­molecular O—H⋯N hydrogen bond. Surprisingly, the 2‐oxazoline ring in mol­ecule B of (II) adopts a ³T₄ (^C2T_C3) conformation, while the 2‐oxazoline ring in mol­ecule A, as well as that in (I) and (III), is nearly planar, as expected. Tetra­mers of mol­ecules of (II) are formed and they are bound together via weak C—H⋯N hydrogen bonds. In (III), strong inter­molecular O—H⋯N hydrogen bonds and weak intra­molecular C—H⋯O hydrogen bonds lead to the formation of an infinite chain of mol­ecules perpendicular to the b direction. This paper also reports a theoretical investigation of hydrogen bonds, based on density functional theory (DFT) employing periodic boundary conditions.     

3,3′‐Dihydr­oxy‐5,5,5′,5′‐tetra­methyl‐2,2′‐thio­dicyclo­hex‐2‐en‐1‐one

Mol­ecules of the title compound, C₁₆H₂₂O₄S, have twofold crystallographic symmetry and are stabilized by strong intra­molecular O—H⋯O hydrogen bonds and very weak inter­molecular C—H⋯O hydrogen bonds, forming layers normal to the c axis. The mol­ecular structure is compared with those of the Se‐ and CH₂‐bridged analogues.     

fac‐Bromo­tri­carbonyl­[2‐(2‐pyridylmethyl)‐2,3‐di­hydro‐1H‐isoindol‐1‐one]­rhenium(I) methanol solvate

The structure of the title compound, fac‐[ReBr(C₁₄H₁₂N₂O)(CO)₃]·CH₄O, consists of neutral mononuclear mol­ecular units of distorted octahedral geometry, with the three carbonyl donors in a facial orientation. The remaining coordination sites are occupied by the Br atom, the pyridine N atom and the ketone O‐atom donor of the ligand. The mol­ecules pack in stacks of antiparallel tapes, with a network of classical (O—H⋯Br) and non‐classical (C—H⋯O) hydrogen bonds between the methanol solvent mol­ecule and the complex mol­ecule.     

4‐(4‐Chloro­benzyl­ideneamino)‐1,5‐dimethyl‐2‐phenyl‐1H‐pyrazol‐3(2H)‐one and 4‐(2‐chloro­benzyl­idene­amino)‐1,5‐dimethyl‐2‐phenyl‐1H‐pyrazol‐3(2H)‐one

The two title compounds, both with formula C₁₈H₁₆ClN₃O, are structurally similar Schiff bases derived from the condensation of 4‐chloro­benzaldehyde or 2‐chloro­benzaldehyde with 4‐amino­anti­pyrine in methanol solution. As expected, both compounds adopt trans configurations about the central C=N bonds. In the crystal structure of the 4‐chloro analogue, mol­ecules are linked through weak C—H⋯O hydrogen bonds, forming chains running along the a axis. In the crystal structure of the 2‐chloro analogue, mol­ecules are linked through weak C—H⋯O and C—H⋯Cl hydrogen bonds, forming layers parallel to the ab plane.     

rac‐(Z)‐Ethyl 2‐bromo‐2‐[(3R,5R)‐3‐bromo‐5‐methyl­tetra­hydro­furan‐2‐yl­idene]acetate

In the title compound, C₉H₁₂Br₂O₃, a (tetra­hydro­furan‐2‐yl­idene)acetate, the double bond has the Z form. In the tetra­hydro­furan group, the relative configuration of the Br atom in the 3‐position and the methyl group in the 5‐position is anti. The compound crystallizes with two independent mol­ecules per asymmetric unit and, in the crystal structure, the individual mol­ecules are linked to their symmetry‐equivalent mol­ecules by C—H⋯O hydrogen bonds, so forming centrosymmetric hydrogen‐bonded dimers.     

trans‐Di­aqua­bis­(thio­semicarb­azido‐κ2N,S)­nickel(II) dimaleate dihydrate

In the title compound, [Ni(CH₅N₃S)₂(H₂O)₂](C₄H₃O₄)₂·2H₂O, the Ni atom lies on a center of symmetry and is coordinated by N and S atoms from two thio­semicarbazide ligands and the O atoms of two water mol­ecules in a distorted octahedral geometry. In the asymmetric unit, the three components are linked together by one O—H⋯O and two N—H⋯O hydrogen bonds. The packing is built from molecular ribbons parallel to the b direction, stabilized by intramolecular hydrogen bonds, and by one N—H⋯S and two N—H⋯O intermolecular hydrogen bonds. The ribbons are further connected into columns by N—H⋯O interactions and then into a three‐dimensional network by three O—H⋯O hydrogen bonds.