The title compound is the hydro­chloride salt of the ethyl ester of l-valine. Inter­molecular inter­actions connect the entities of the asymmetric unit into sheets lying parallel the the bc plane.

The title compound contains zigzag polymeric chains built up from nine-coordinated DyIII centers and bridging 5-az­an­ium­yl­isophthalate ligands.

The title compound is the acetal of 4-chloro­benzaldehyde and 1,3-propane­diol. In the crystal, weak C—H⋯O contacts connect the mol­ecules to centrosymmetric dimers.

The title compound forms strands along the b-axis direction via hydrogen bonds from the tolyl group to the sulfonyl oxygen atoms. The tricyclic framework is almost planar and the two six-membered aromatic substituents are nearly coparallel.

The ZnII atom in the title compound has distorted octa­hedral N2O4 coordination geometry. The inter­molecular inter­actions in the crystal structure consist of O–H⋯O and weak C–H⋯O hydrogen bonds.

The title quaternary inter­metallic material is a new γ-brass obtained using a high-pressure sinter­ing process.

In the title compound, the dihedral angle between the 2H-chromen-2-one moiety and the C—CO2 ester grouping is 54.30 (5)°. In the crystal, the mol­ecules are linked by C—H⋯O hydrogen bonds forming C(6) [100] chains.

The title compound, C21H38N+·Br−·H2O, is the bromide salt of a quarternary pyridinium cation bearing a hexa­decyl chain on the nitro­gen atom. One mol­ecule of solvent water is present in the asymmetric unit. Classical hydrogen bonds of the O—H⋯Br type are observed next to C—H⋯Br and C—H⋯O contacts that connect the entities of the title compound to sheets parallel to the ab plane.

In the title compound, the complete organic cation, which adopts a typical chair conformation, is generated by crystallographic inversion symmetry and one of the N-bonded H atoms is half occupied. The sodium ion (site symmetry m) at the centre of the complex anion adopts a distorted trigonal–bipyramidal coordination geometry with the water mol­ecules in the equatorial sites and the bromide ions in the axial sites. In the extended structure, O—H⋯Br hydrogen bonds generate a porous ‘honeycomb' three-dimensional network of complex anions encapsulating [010] channels occupied by the cations.

In the bis-chelated mononuclear nickel(II) title complex with benzohydrazide ligands bearing an all­yloxy group, the nickel(II) atom exhibits a slightly distorted square-planar coordination environment with the metal located on a crystallographic center of symmetry that induces a trans configuration of the N,O chelating ligands..

The title compound is a derivative of cyclo­hexa­necarb­oxy­lic acid bearing a hydroxyl group in its α-position and is a polymorph of the previously reported monoclinic form.

The crystal structure of a reagent frequently used for the preparation of buffer solutions is reported, showing that the mol­ecule lies on a crystallographic mirror plane, and has a bent conformation.

The title compound is a hydrated, partially protected derivative of d-gluco­pyran­ose. Inter­molecular inter­actions connect the entities of the asymmetric unit to a three-dimensional network.

In the title compound, much of the mol­ecule (excluding the pyridinic ring) is approximately planar. In the extended structure, various hydrogen bonds combine to form a layer structure parallel to (111).

The title acridine derivative, which has two 2-methyl­but-3-yn-2-ol moieties at the 2,7-positions, was synthesized by Sonogashira coupling reaction. In crystal, a columnar structure is formed by the π–π stacking of acridine units. The 2-methyl­but-3-yn-2-ol moieties form inter­molecular hydrogen bonds.

In the title compound, the dihedral angle between the planes of the pyridine and oxo­pyrroli­dine rings is 6.9 (2)°. In the crystal, inversion dimers linked by pairwise N—H⋯O hydrogen bonds generate R22(14) loops.

The extended structure of the title compound features strong N—H⋯N hydrogen bonds forming infinite C(4) chains propagating along the c-axis direction.

In the title compound, C14H14O4, the dihedral angle between the coumarin nucleus and the penta­noate moiety is 84.6 (9)°. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds into centrosymmetric dimers with an R22(8) graph-set motif, and π–π inter­actions are also observed.

In the title compound, the six-membered ring is disordered over two half-chair orientations. In the crystal, infinite [001] chains linked by N—H⋯N hydrogen bonds occur.

The compound is a neutral discrete complex where the silver(I) center is coordinated by three phospho­rus atoms from three distinct PTA ligands and one carbon atom from the nitrile ion, resulting in a distorted tetra­hedral geometry around the Ag centre.

A trinuclear copper(II)–levofloxacin complex, (C18H22FN3O4)2[Cu3Cl9(H2O)2]Cl, was synthesized and its crystal structure determined. It features five-coordinated CuII centres with Jahn–Teller distortion and a three-dimensional hydrogen-bonded supra­molecular network.

The title compound crystallizes in ortho­rhom­bic space group Pnma with both cations and anions lying on a mirror plane in the crystal. Parallel mol­ecules form stacks with inter­planar spacing 3.1473 (2) Å, but slipped by 1.97 Å.

The title mol­ecular salt, C23H21N2+·C6H2N3O7−, featuring discrete ion pairs, crystallizes from ethanol through slow solvent evaporation. In the crystal, the imidazolium cation and the picrate anion are linked by N—H⋯O hydrogen bonds as a result of proton transfer from picric acid to the pyrimidine-type nitro­gen atom of the imidazole ring.

Both six-membered rings in the title bi­cyclo­[3.3.1] system, adopt a chair conformation. Hydrogen bonds from the hy­droxy group to the ether bridge connect the mol­ecules into zigzag chains: single-enantiomer chains propagating along the b-axis direction form the crystal.

The title hydrated salt, a new monoclinic polymorph, crystallizes in space group P21/c. The components pack in sheets in the ab plane and these sheets are hydrogen bonded to their neighbours, generating a three-dimensional network.