1- (Phthalazin-l'-yl-amino)-3-chloro-4-aryl-4H-(4o-rm ethyl)-2-azetidinones (3) were prepared by cycloaddition of-methyl substituted benzal hydrazinophthalazine (2) with chloro acetylchloride. The hydrazone (2) was synthesised by the condensation of 1- hydrazinophthalazine (1) with substituted aromatic aldehydes, ketones 7 acetophenones. 1- Hydrazinophthalazine was prepared from the phthal...

The title chromene, C(14)H(16)O(4), was isolated from the stems of Polyalthia plagioneura Diels. The mol-ecular structure is stabilized by an intra-molecular O-H⋯O hydrogen bond, which generates an S(6) ring. In the crystal, the mol-ecules are linked by C-H⋯O inter-actions, generating [010] chains.

In the title compound, C(29)H(23)NO(2), the pyrrolidine ring adopts a twisted conformation about one of the C-N bonds. The acenaphthone ring (r.m.s. deviation = 0.025 Å) lies almost perpendicular to the pyrrolidine ring [dihedral angle = 88.08 (8)°]. The dihedral angle between the phenyl rings is 88.12 (11)°. In the crystal structure, weak C-H⋯π inter-actions connect the mol-ecules.

In the title compound, C(13)H(9)NO(6), the coumarin system has the benzene ring aligned at 0.61 (18)° with respect to the pyrone ring. An intra-molecular O-H⋯O hydrogen bond stabilizes the mol-ecular conformation and a C-H⋯O contact also occurs. In the crystal, weak C-H⋯O inter-actions link the mol-ecules, forming inversion dimers.

In the title compound, C(15)H(12)FN(3)O, the benzotriazole ring system is essentially planar, with a maximum deviation from the least-squares plane of 0.016 (3) Å. The dihedral angle between this ring system and the fluoro-substituted benzene ring is 67.97 (2)°. The crystal structure is stabilized by weak inter-molecular C-H⋯N inter-actions.

The mol-ecule of the title compound, C(12)H(12)O(2), is essentially planar, with a maximum deviation from the mean plane of all non-H atoms of 0.038 (1) Å for the methyl C atom in the 8-position. The crystal structure is characterized by anti-parallel π-π stacking along the c axis, with centroid-centroid distances as short as 3.866 (1) Å. In the crystal, C-H⋯O hydrogen bonds connect the mol-ecu...

In the title compound, C(18)H(16)N(2)O(2), the central pyridazine ring forms dihedral angles of 77.08 (5)° and 84.62 (5)° with the two benzene rings. The dihedral angle between the two benzene rings is 68.18 (4)°. A very weak intra-molecular C-H⋯N hydrogen bond and an intra-molecular C-H⋯π inter-action occur. The crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen bonds and w...