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

Intermolecular Interactions of 3,5-bis(4-Methoxyphenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide in a Cocrystal with 1,3-bis(4-Methoxyphenyl)prop-2-en-1-one and Dimethylformamide Solvate

Two new multicomponent crystals consisting of 3,5-bis(4-methoxyphenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide (1) with 1,3-bis(4-methoxyphenyl)prop-2-en-1-one (2) and with dimethylformamide (DMF), both in 1:1 ratio, prepared and structurally characterized. The occurrence of 1 in different crystal structures enabled a comparison of hydrogen bonding contacts between the two structures as well as with the known structure of pure 1. The backbone of molecule 1 was similar in the structures but the orientation of the methoxy groups varied. Molecule 1 was involved in various combinations of the possible hydrogen bonding contacts, including N–H…O=C, N–H…OMe, and N–H…S. Both N–H hydrogens in the cocrystal (1–2) and the solvate (1-DMF) participated in hydrogen bonding but only one hydrogen atom took part in the structure of pure 1. The S atom accepted contacts in both the structures of pure 1 and cocrystal 1–2 but not in that of the 1-DMF solvate. The oxygen atoms of both methoxy groups acted as acceptors in the structure of pure 1, whereas one oxygen was involved in the 1-DMF solvate and none in cocrystal 1–2.

Convenient Synthesis of New Heterocycles Containing the Quinoxaline Ring System

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The aim of the current article was to describe simple procedures for the synthesis of new heterocycles incorporating the quinoxaline moiety using benzene-1,2-diamine and quinoxaline-2,3- dithiol as precursors. Simple synthetic methods are described for the synthesis of new heterocycles using commercially available chemicals. Also, the new compounds were determined using analytical and spectroscopic methods including single X-ray crystal structures. A series of new heterocycles containing the quinoxaline nucleus have been synthesized in good yields using simple and convenient procedures. A process has been described for the synthesis of new heterocycles containing the quinoxaline moiety that might be difficult to synthesize by other routes.

Synthesis and Structure Elucidation of N′-(4-Methoxybenzylidene)-5-methyl-1-phenyl-1H-1,2,3-triazole-4-carbohydrazide

N′-(4-Methoxybenzylidene)-5-methyl-1-phenyl-1H-1,2,3-triazole-4-carbohydrazide (3) was synthesized in a yield of 88% from an acid-catalyzed reaction of 5-methyl-1-phenyl-1H-1,2,3- triazole-4-carbohydrazide and 4-methoxybenzaldehyde in ethanol under reflux for 2.5 h. The structure of 3 was confirmed by the data obtained from infrared, nuclear magnetic resonance, mass spectroscopy, single crystal X-ray diffraction, and microanalysis.