Synthesis and Antimicrobial Evaluation of New 5-(2-Hydroxyphenyl)-3-(4-(Phenylthio)Phenyl)-1H-Pyrazole-2(5H)-Carbothioamide Analogues of 2-(4-(Phenylthio)Phenyl)-4H-Chromen-4-One

Synthesis of Chromone-Related Pyrazole Compounds

Chromones, six-membered oxygen heterocycles, and pyrazoles, five-membered two-adjacent-nitrogen-containing heterocycles, represent two important classes of biologically active compounds. Certain derivatives of these scaffolds play an important role in medicinal chemistry and have been extensively used as versatile building blocks in organic synthesis. In this context, we will discuss the most relevant advances on the chemistry that involves both chromone and pyrazole rings. The methods reviewed include the synthesis of chromone-pyrazole dyads, synthesis of chromone-pyrazole-fused compounds, and chromones as starting materials in the synthesis of 3(5)-(2-hydroxyaryl)pyrazoles, among others. This review will cover the literature on the chromone and pyrazole dual chemistry and their outcomes in the 21st century.

Iodine-catalysed regioselective thiolation of flavonoids using sulfonyl hydrazides as sulfenylation reagents

Iodine-catalysed regioselective sulfenylation of flavonoids including flavone, flavonol, dihydroflavone, isoflavone and aurone derivatives by sulfonyl hydrazides was developed.

Crystal structure of (E)-1-(2,4-di-nitro-phen-yl)-2-[(E)-5-phenyl-1-(p-tol-yl)pent-2-en-4-yn-1-yl-idene]hydrazine

In the title compound, C24H18N4O4, the plane of the phenyl ring is inclined to those of the toluene ring and the di-nitro-substituted benzene ring by 66.96 (19) and 47.06 (18)°, respectively, while the planes of the two benzene rings are inclined to one another by 36.26 (19)°. There is an intra-molecular N-H⋯O hydrogen bond between the NH group and the O atom of a nitro group, forming an S(6) ring motif. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds and C-H⋯π inter-actions, forming a three-dimensional network. There are also weak π-π inter-actions present involving the phenyl ring and the di-nitro-substituted benzene ring [inter-centroid distance = 3.741 (2) Å].

(E,Z)-1-(4-Chloro-phen-yl)-5-phenyl-5-(phenyl-sulfan-yl)penta-2,4-dien-1-one

The penta-2,4-dien-1-one fragment of the title compound, C₂₃H₁₇ClOS, is twisted by 20.0 (3)°, as measured by the dihedral angle between the planes of the carbonyl group and its attached C atom and the distant C=C double bond and its attached C atom. The 4-chloro­phenyl group forms a dihedral angle of 4.0 (3)° with the adjacent carbonyl group. Conjugation between the phenyl ring and the C=C double bond is absent; the dihedral angle between the phenyl ring and the C—C=C fragment is 34.3 (2)°. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds, forming chains parallel to the b-axis direction.