Synthesis and antimicrobial activity of some new 4-hetarylpyrazole and furo[2,3-c]pyrazole derivatives.

In continuation of our efforts to find a new class of antimicrobial agents, a series of 4-hetarylpyrazoles and furo[2,3-c]pyrazoles were prepared via the reaction of 2-chloro-1-(5-hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)ethanone (1) with an appropriate nucleophilic reagents. These compounds were screened for their antibacterial activity against Gram-positive bacteria (Bacillus subtilis and Bacillus thuringiensis), Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and antifungal activity against Fusarium oxysporum and Botrytis fabae. Among the synthesized compounds, 1-(5-(5-hydroxy-3-methyl-1-phenyl-1H-pyrazole-4-yl)-2-methylfuran-3-yl)ethanone (12) showed equal activity with chloramphenicol against B.

Synthesis and antimicrobial evaluation of some new thiazole, thiazolidinone and thiazoline derivatives starting from 1-chloro-3,4-dihydronaphthalene-2-carboxaldehyde.

The thiosemicarbazones (3 and 6) and N-arylidene cyanoacetohydrazide (12) were prepared and used as key intermediates for the synthesis of 4-thiazolidinones (4, 5, 7-9), thiazoles (10a,b and 11a-d) and thiazoline (13) derivatives. Treatment of 13 with a mixture of triethylorthoformate and acetic anhydride afforded thiazolo[5,4-d]pyrimidinone derivative (14). The newly synthesized compounds were characterized by IR, (1)H NMR and mass spectral studies.