Two new triterpenoids with antimicrobial activity from the leaves and twigs of Orophea yunnanensis

Two new triterpenoids, 3-O-(4’,5’-dihydroxybenzoyl)-lup-20(29)-en (1) and 3-O-(6’-desmethysyringyl)-13α-methyl-27-norolean-14-en-3β-ol (2), were isolated from the leaves and twigs of Orophea yunnanensis. Their structures were identified by extensive spectroscopic experiments (NMR and MS) and comparison with literature data. Compounds 1 and 2 exhibited the moderate inhibitory activity against Sclerotinia sclerotiorum, Ceratocystis fimbriata and Verticillium dahliae Kleb with MIC values from 50 to 25 μg/mL, and also displayed the weak activity selectively against tested bacteria strains with MIC values from 100 to 50 μg/mL.