Synthesis and antimicrobial activities of some novel bis-pyrazole derivatives containing a hydrophosphoryl unit

Abstract

Vilsmeier‐Haack reaction conditions were applied on some methyl ketone aryl phosphonicdihydrazones to yield some interesting bis‐pyrazole derivatives containing a hydro‐phosphoryl unit. Bis‐{4‐formyl‐3‐aryl‐1H‐pyrazol‐1‐yl}phosphine oxides (4a,b) were condensed with some nucleophiles such as aniline, phenacyltriphenylphosphonium bromide and 4‐phenylthiosemicarbazide followed by treatment with thioglycolic acid, diethyl phosphite and/or acetic anhydride to yield a novel class of bis‐pyrazoles containing sulfur and phosphorus derivatives. Most of the newly synthesized compounds were evaluated for their in vitro antimicrobial activities.