Three new labdane diterpenes, 12 alpha,17-epoxy-3 beta-hydroxy-8(9),13- labdadien-16,15-olide (aulacocarpinolide) [1], methyl 8 beta,17:14 zeta,15-diepoxy-3 beta-hydroxy- 12E-labden-16-oate (aulacocarpin A) [2], and methyl 8 beta,17:14 zeta,15-diepoxy-3 beta,6 beta- dihydroxy-12E-labden-16-oate
Antimicrobial activity-directed fractionation of the seeds of Aframomum longifolius (Zingiberaceae) afforded two new labdane-type diterpenoids, 15-hydroxy-15-methoxylabda-8(17), 12( E)-dien-16-al (aframolin A) ( 1) and 8beta(17)-epoxy-15,15-dimethoxylabd-12( E)-en-16-al (aframolin B) ( 2), together