The title compound, C(11)H(8)O(4), features an almost planar mol-ecule (r.m.s. deviation = 0.033 Å for all non-H atoms). In the crystal, the mol-ecules are linked via C-H⋯O hydrogen bonds, forming two-dimensional networks lying parallel to (1-21).

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...

In the title compound, [Fe(C5H5)(C14H10NO3)], the cyclo-penta-dienyl rings are in an eclipsed conformation and the pyran ring adopts a half-chair conformation. The mean plane of the pyran ring makes dihedral angles of 79.33 (1) and 80.73 (1)°, respectively, with the substituted and unsubstituted cyclo-penta-dienyl rings. In the crystal, pairs of C-H⋯O hydrogen bonds link the mol-ecules into inv...

New chiral camphane-derived benzisoselenazol-3(2H)-ones and corresponding diselenides have been synthetized using a convenient one-pot procedure. Se-N bond was efficiently converted to an Se-Se bond, which could also be easily re-oxidized to the initial benzisoselenazolone moiety. The antioxidant activity of camphor derivatives was evaluated and compared to the reactivity of a series of N-amino...

Successful implementation of ultrasound irradiation for the rapid synthesis of a novel series of 3-[1-(4-substituted-5-(aryldiazenyl)thiazol-2-yl)hydrazono)ethyl]-2H-chromen-2-ones 5a-h, via reactions of 2-(1-(2-oxo-2H-chromen-3-yl)ethylidene) thiosemicarbazide (2) and the hydrazonoyl halides 3(4), was demonstrated. Also, a new series of 5-arylidene-2-(2-(1-(2-oxo-2H-chromen-3-yl)ethylidene)hyd...

The title compound, C(20)H(24)O(4), was synthesized from the reaction of 2-oxo-2H-chromene-3-acyl chloride and menthol. The mean plane of the ester group and that of the four essentially planar (maximum deviation 0.0112 Å) C atoms of the chair-form cyclo-hexyl ring form dihedral angles of 43.8 (3) ° and 81.8 (1)°, respectively, with the mean plane of the coumarin ring system. In the crystal str...

In the cation of the title compound, C(6)H(6)N(5) (+)·CF(3)COO(-), the pyridine and tetra-zole rings are nearly coplanar, making a dihedral angle of 2.49 (19)°. In the crystal, the cations and anions are connected by inter-molecular N-H⋯O and N-H⋯(F,O) hydrogen bonds, forming centrosymmetric [2 + 2] aggregates, which stack along the a axis.

The title compound, C(16)H(12)O(2), is a coumarin which was isolated from stones of the Chinese traditional medicine Clausena lansium. The pyrone ring is almost planar, with a mean deviation of 0.0135 (4) Å. The benzene ring (A) of the benzopyrone unit forms dihedral angles of 1.82 (5) and 72.86 (2)° with the pyrone ring and the substituent benzene ring, respectively. The crystal structure is s...

The title compound, C(19)H(14)O(4), was prepared by the reaction of 2-oxo-2H-chromene-3-acyl chloride with cinnamic alcohol. The whole mol-ecule is not planar, the dihedral angle between the planes of coumarin and benzene rings being 13.94 (4)°, but the plane of the coumarin ring and that of the ester group are almost coplanar, making a dihedral angle of 2.9 (1)°. In the crystal structure, weak...