Synthesis of new pyrazolines and their biological evaluation as antimicrobial agents

2-Diazopropane and diazo compounds derived from aromatic aldehydes were reacted with aromatic esters of 3-hydroxyprop-1-yne to give the aromatic esters of 5-hydroxymethyl-3-substituted pyrazoles. Anti-microbial screening using the Gram positive (Staphylococcus aureus and Enterococcus fecalis) and Gram negative (Escherichia coli and Klebsiella pneumoniae) bacteria and the yeast Candida albicans, showed that these compounds had promising activity against both Gram positive and Gram negative bacteria.