Crystal structure of (4E)-4-(8-meth-oxy-2H-chromen-2-yl-idene)-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one.

In the title compound, C20H16N2O3, the phenyl substituent attached to the pyrazole ring makes a dihedral angle of 4.87 (7)° with the rest of the mol-ecule. In the crystal, mol-ecules are connected into inversion dimers of the R 2 (2)(14) type by pairs of C-H⋯O inter-actions.

Crystal structure of (4Z)-4-[(2E)-3-(2-chloro-phen-yl)-1-hy-droxy-prop-2-en-1-yl-idene]-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one.

In the title compound, C19H15ClN2O2, the pyrazole ring is almost planar (r.m.s.

Crystal structure of (4Z)-4-[(2E)-3-(4-chloro-phen-yl)-1-hy-droxy-prop-2-en-1-yl-idene]-5-methyl-2-phenyl-1H-pyrazol-5(4H)-one.

In the the asymmetric unit of the title compound, C19H15ClN2O2, there are two symmetry-independent mol-ecules, which adopt similar conformations. The largest difference is observed in the dihedral angles between the phenyl and the pyrazole fragments [17.00 (12) and 23.

Crystal structure of (4Z)-4-[(2E)-1-hydroxy-3-(naphthalen-2-yl)prop-2-en-1-yl-idene]-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one.

In the title compound, C23H18N2O2, the pyrazole ring subtends dihedral angles of 2.01 (13) and 1.55 (10)° with the pendant benzene ring and the naphthalene ring system, respectively.

(4Z)-4-[(2E)-1-Hydr-oxy-3-(4-methoxy-phen-yl)prop-2-en-ylidene]-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one.

The title compound, C(20)H(18)N(2)O(4), is a chalcone derivative of pyrazole. The pyrazole ring is inclined at a dihedral angle of 19.29 (12)° to the methoxy-phenyl ring mean plane, and by 1.