Synthesis, modification, and antimicrobial activity of the N-methylpiperazinyl amides of triterpenic acids

N -methylpyperazinyl amides of betulinic, platanic, glycyrrhetic, oleanolic, ursolic, and moronic acids were synthesized and modified. Betulin and betulonic acid showed antimicrobial activity against Staphylococcus aureus at a concentration of 90 mg/ml, and betulin manifested a bacteriostatic effect against Klebsiella pneumoniae at a concentration of 60 mg/ml. Among the studied N -methylpyperazinyl amides, the highest activity against S. aureus was observed for a betulonic acid derivative.