Synthesis and Reactions of Some New Thiazolylpyrazole Derivatives and Related Compounds

Abstract

Thiazolylpyrazoles 2-7 were prepared from the reaction of 2-hydrazino-4-phenylthiazole (1) with yielidenenitriles; S,S- or N, S-acetals or ethoxymethylenemalononitrile. 5-Amino-1-(4-phenyl-thiazol-2-yl)-1H-pyrazole-4-carbonitrile (7) reacted with phenyl isothiocyanate, carbon disulphide, formic acid, and formamide to furnish the pyrazolopyrimidines 8, 9, 16, and 17, respectively. Reaction of compound 7 with malononitrile afforded pyrazolopyridine 10, while its reaction with acetic anhydride, acetyl chloride, sulfuric acid, and triethylorthoformate gave thiazolylpyrazoles 12, 13, 15, and 18, respectively.

Keywords:

• 2-hydrazino-4-phenylthiazole
• pyrazolopyridine
• pyrazolopyrimidines
• thiazolylpyrazoles

Notes

^aUncorrected;

^bsatisfactory microanalysis obtained C; – 0.47, H; – 0.25, N; – 0.39, S; – 0. 35;

^cmeasured by Nicolet FT-IR 710 Spectrophotometer; and

^dmeasured by ¹H NMR LA 400 MHz (Jeol) Assiut University.