Mohammed Baashen

A simple procedure for the synthesis of novel 3-(benzofur-2-yl)pyrazole-based heterocycles

Abstract3-(Benzofuran-2-yl)-1-phenyl-1H-pyrazole-4-carbaldehyde was used, as a precursor for the synthesis of a series of novel heterocycles by facile reactions with 3-oxo-3-phenylpropanenitrile, 2-cyanoethanethioamide, and various hydrazides such as cyanoacetohydrazide, acetohydrazide, and carbohydrazide derivatives. The structures of the products were confirmed by various spectroscopic methods along with the X-ray crystal structures.Graphical Abstract

Crystal structure of 4-(2,2-di­methyl­propanamido)­pyridin-3-yl N,N-diiso­propyl­dithio­carbamate

In the title compound, C17H27N3OS2, the amide group is approximately coplanar with the pyridine ring [dihedral angle = 1.6 (1)°], whereas the dithiocarbamate group is nearly perpendicular to the pyridine ring [dihedral angle = 76.7 (1)°]. In the crystal, pairs of weak C—H⋯O hydrogen bonds link the molecules into inversion dimers.

Quinoxaline-2,3(1H,4H)-dithione: Synthesis and reactions

GRAPHICAL ABSTRACT ABSTRACT Quinoxaline-2,3(1H,4H)-dithione can be synthesized efficiently through the thionation of quinoxaline-2,3(1H,4H)-dione with phosphorous pentasulfide. It can also be obtained by reaction of 2,3-dichloroquinoxaline with thiourea or sodium hydrogen sulfide. The most common reactions of quinoxaline-2,3(1H,4H)-dithione involve deprotonation and electrophilic attack at the sulfur atoms to give various substituted derivatives and poly-fused heterocyclic ring systems. The current review aims to provide a survey of the developments in quinoxaline-2,3(1H,4H)-dithione chemistry until 2016.

Synthetic profiles to pyrazolylquinoxalines

Pyrazolylquinoxalines act as important intermediates for the production of novel derivatives with potential biological applications. The current review covers the synthesis of 2(3)-(pyrazol-1(3(5),4)-yl)quinoxalines published from 1978 until present.

Crystal structure of 3-(5-methyl-1-p-tolyl-1H-1,2,3-triazol-4-yl)-1-phenyl-1H-pyrazole-4-carbaldehyde, a rare Z' = 3 structure, C20H17N5O

Abstract C20H17N5O, triclinic, P1̅ (no. 2), a = 11.5358(7) Å, b = 13.8746(9) Å, c = 16.3942(10) Å, α = 85.958(5)°, β = 87.407(5)°, γ = 87.619(5)°, V = 2612.8(3)Å3, Z = 6, Rgt(F) = 0.0607, wRref(F2) = 0.1510, T = 293(2) K.

Crystal structure of 2-(3-(benzofuran-2-yl)-5-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl)-4-(4-chlorophenyl)thiazole, C26H17ClFN3OS

Abstract C26H17ClFN3OS, monoclinic, P21/c (no. 14), a = 6.4955(2) Å, b = 14.6143(5) Å, c = 22.6492(8) Å, β = 94.568(1)°, V = 2143.20(12) Å3, Z = 4, Rgt(F) = 0.0461, wRref(F2) = 0.1069, T = 100 K.

Crystal structure of 3-amino-2-ethyl-quinazolin-4(3H)-one.

The molecule of the title compound, C10H11N3O, is planar, including the ethyl group, as indicated by the N—C—C—C torsion angle of 1.5 (2)°. In the crystal, inversion-related molecules are stacked along the a axis. Molecules are oriented head-to-tail and display π–π interactions with a centroid-to-centroid distance of 3.6664 (8) Å. N—H⋯O hydrogen bonds between molecules generate a ‘step’ structure through formation of an R 2 2(10) ring.