A new triterpene from Barringtonia asiatica.

The freeze-dried bark of Barringtonia asiatica afforded a new triterpene: (3β,11α)-11-hydroxyolean-12-en-3-yl palmitate (1). The bark also yielded mixtures of (3β)-olean-12-en-3-yl palmitate (2a), (3β)-urs-12-en-3-yl palmitate (2b) and (3β)-olean-18-en-3-yl palmitate (2c) in a 2:1:4 ratio; β-amyrin (3a), α-amyrin (3b) and germanicol (3c) in a 3:1:4 ratio; 22-O-tigloylcamelliagenin A (4a) and betulinic acid (4b) in a 2:1 ratio; olean-12-en-3β,16β,22α-triol (5), β-sitosterol, spinasterol, squalene and trilinolein. The roots yielded 2a-c and 3a-c as well as trilinolein, spinasterol and squalene, while the flowers afforded verimol k (6), linoleic acid, spinasterol, squalene, phytyl fatty acid ester and trilinolein. Compounds 1-4 and 6 were tested for antimicrobial property against seven microorganisms. All compounds tested exhibited slight activity against Candida albicans and were found inactive against Escherichia coli, Bacillus subtilis, Trichophyton mentagrophytes and Aspergillus niger. Except for the mixture of 4a and 4b that proved to be inactive, all the compounds were slightly active against the bacterium Staphylococcus aureus, while 3a-c were slightly active against Pseudomonas aeruginosa.