organic compounds
Open access
The asymmetric unit of the title compound, 2C15H16N6O3·C3H7NO·H2O, contains two independent ethyl 6-methyl-2-oxo-4-[4-(1H-tetrazol-5-yl)phenyl]-1,2,3,4-tetrahydropyrimidine-5-carboxylate molecules, in which the dihedral angles between the tetrazole and benzene rings are 20.54 (12) and 12.13 (12)°. An intramolecular C—HO hydrogen bond occurs in each molecule. In the crystal, N—HO, N—HN, O—HO and O—HN hydrogen bonds, as well as weak C—HO and C—HN hydrogen bonds, link the molecules into a three-dimensional supramolecular architecture. π–π stacking is also observed between parallel tetrazole rings of adjacent molecules, the centroid–centroid distance being 3.482 (6) Å.
organic compounds
Open access
In the title compound, C16H10N4O2·0.17H2O, prepared by the one-step condensation reaction of isatin with hydrazine hydrate under microwave irradiation, the complete organic molecule is generated by crystallographic inversion symmetry and therefore exists in an S-trans conformation. In the crystal, molecules are linked by N—HO hydrogen bonds, generating a three-dimensional framework with [001] channels, which are occupied by the disordered water molecules.
data reports
Open access
In the title molecule, C14H18ClN5O2S, the six atoms of the 1,6-dihydropyridazine ring are essentially coplanar (r.m.s. deviation = 0.008 Å), and the dihedral angle between this and the 1,3,4-thiadiazole ring is 62.06 (10)°. In the crystal, centrosymmetrically related molecules are linked by intermolecular C-H-O hydrogen bonding to form a supramolecular dimer. The terminal ethyl group is statistically disordered over two positions.