Two Novel Cytotoxic and Antimicrobial Triterpenoids from Pseudolarix kaempferi

Two novel antimicrobial and cytotoxic triterpenoids, isopseudolarifuroic acids A (1) and B (2), were isolated from the bark of Pseudolarix kaempferi. The structural elucidation of two novel compounds was carried out mainly by spectroscopic methods, and also by computer modeling. Compounds 1 and 2 exhibited significant cytotoxic activities against several tumor cell lines. Compound 1 also showed most potent antimicrobial activities against both Gram-positive and Gram-negative bacteria.