Antimicrobial and antineoplastic activities of new 4-diazopyrazole derivatives

Several new 4-diazopyrazole derivatives were prepared by the reaction of 3-methyl-5(substituted-benzamido)pyrazoles with an excess of nitrous acid in acetic acid solution. The compounds were tested for antiretroviral activity in HIV-1 infected MT-4 cells and antiproliferative effects against a panel of human leukemia, lymphoma and solid tumor cell lines. They were also tested for activity against representative gram-negative (Shigella, Salmonella) and gram-positive (S. aureus, D group Streptococcus) bacteria as well as fungi (C. albicans, C. paratropicalis, C. neoformans and A. fumigatus). Compounds were devoid of anti HIV-1 and antimicotic activities, whereas they were active against tumor cell lines, with inhibitory activity (IC50) in the range 2.4-20 mu M and bacteria. The highest microbial susceptibility was shown by gram-positive bacteria, with minimum inhibitory concentrations in the range 0.8-12.5 mu M. (C) Elsevier, Paris.