3,3'-(Phenyl-methyl-ene)bis-(1-ethyl-3,4-di-hydro-1H-2,1-benzo-thia-zine-2,2,4-trione): single-crystal X-ray diffraction study, quantum-chemical calculations and Hirshfeld surface analysis.

The title compound, C27H26N2O6S2, possesses potential anti-microbial, analgesic, and anti-inflammatory activity. This compound has three tautomeric forms, which relative energies were estimated with quantum-chemical calculations. All these tautomers (dienol form 7A, keto-enol form 7B, and diketo form 7C) were optimized by the M06-2X/cc-pVTZ method in a vacuum, using the PCM model with chloro-form and DMSO as solvent. The diketo form of the title compound proved to be the most energetically favourable as compared to the keto-enol or dienol forms. The diketo form can exist as three possible stereoisomers with the same configuration of one stereogenic center and different configurations of the stereogenic centers at two other atoms: ( R , R , R ), (S , R , S ) and ( R , R , S ). The ( R , R , S ) stereoisomer was found in the crystal phase. It was revealed that the thia-zine rings of equivalent benzo-thia-zine fragments have different conformations, (a sofa or a half-chair). The two bicyclic fragments connected through the phenyl-methyl-ene group are oriented almost orthogonal to each other, subtending a dihedral angle of 82.16(7)°.

N-tert-Butyl-2-{2-[2-(4-chloro-phen-yl)-4-hy-droxy-1-(5-methyl-isoxazol-3-yl)-5-oxo-2,5-di-hydro-1H-pyrrol-3-yl]-N-(4-meth-oxy-phen-yl)acetamido}-2-(4-meth-oxy-phen-yl)acetamide methanol monosolvate: single-crystal X-ray diffraction study and Hirshfeld surface analysis.

The title compound, C36H37ClN4O7·CH3OH, which crystallizes as a methanol solvate, may possess biological activity, which is inherent for a natural peptide or protein. In the crystal, mol-ecules of the title compound form hydrogen-bonded tetra-mers with the solvate mol-ecules acting as bridges as a result of the O-H⋯O and N-H⋯O inter-molecular hydrogen bonds. Hirshfeld surface analysis was used to study the different types of inter-molecular inter-actions whose contributions are: H⋯H = 53.8%, O⋯H/H⋯O = 19.0%, C⋯H/H⋯C = 14.8%, Cl⋯H/H⋯Cl = 5.3%, N⋯H/H⋯N = 3.2%.

The first coordination complex of (5R,6R,7S)-5-(furan-2-yl)-7-phenyl-4,5,6,7-tetra-hydro-[1,2,4]triazolo[1,5-a]pyrimidin-6-amine with zinc(II) acetate-chloride.

The title complex, systematic name catena-poly[[[acetato-chlorido-zinc(II)]-µ-(5R,6R,7S)-5-(furan-2-yl)-7-phenyl-4,5,6,7-tetra-hydro-[1,2,4]triazolo[1,5-a]py-rimi-din-6-amine] monohydrate], {[Zn(C2H3O2)Cl(C15H15N5O)]·H2O} n , is the first coordination complex in which the neutral tetra-hydro-triazolo-pyrimidine derivative acts as bridging ligand between two zinc mol-ecules. As a result, polymeric chains of the coordination complex are found. The coordination of the zinc metal atom occurs with the lone pairs of the triazolo nitro-gen atom and amino group. The positive charge of the zinc atom is compensated by the chlorine anion and deprotonated acetic acid. The coordination complex exists as a monohydrate in the crystalline phase. The water mol-ecules bind neighbouring polymeric chains by the formation of O-H⋯O, O-H⋯Cl and N-H⋯O hydrogen bonds.

2-Amino-4-(4-chloro-1-ethyl-2,2-dioxo-1H-benzo[c][1,2]thia-zin-3-yl)-7,7-dimethyl-5-oxo-5,6,7,8-tetra-hydro-4H-chromene-3-carbo-nitrile: single-crystal X-ray diffraction study and Hirshfeld surface analysis.

In the title compound, C22H22ClN3O4S, which has potential non-steroidal anti-inflammatory activity, the benzo-thia-zine and cyclo-hexenone rings both adopt a distorted sofa conformation while the 4H-pyrane ring adopts a very flattened sofa conformation. The two bicyclic fragments are skewed to each other, with the dihedral angle between their least-squares planes being 72.8 (1)°. In the crystal, the mol-ecules form a hydrogen-bonded chain parallel to the a axis due to N-H⋯O and N-H⋯Cl hydrogen bonds. Neighbouring chains are linked by C-H⋯N, C-H⋯O and π-π stacking inter-actions. Hirshfeld surface analysis was used to investigate the importance of the different types of inter-molecular inter-actions whose contributions are: H⋯H = 44.7%, O⋯H/H⋯O = 21.8%, N⋯H/H⋯N = 11.9%, C⋯H/H⋯C = 9.5%, Cl⋯H/H⋯Cl = 7.2%. Parts of the mol-ecule, viz. the phenyl ring and the ethyl side chain, are equally disordered over two sets of sites.