Constituents of Caesalpinia crista from Indonesia.

Ten new furanocassane-type diterpenes named, caesalpinins H-P (1-9) and norcaesalpinin F (10), were isolated from the CH(2)Cl(2) extract of the seed kernels of Caesalpinia crista, together with 13 known diterpenes. Their structures were determined based on the spectroscopic analysis. Among the isolated compounds, caesalpinin N (7) represents the first example of furanocassane-type diterpene possessing an aldehyde group at C-14.

Cassane- and norcassane-type diterpenes from Caesalpinia crista of Indonesia and their antimalarial activity against the growth of Plasmodium falciparum.

The CH2Cl2 extract of the seed kernels of Caesalpinia crista, which exhibited promising antimalarial activity against Plasmodium berghei-infected mice in vivo, was examined and resulted in the isolation of seven new furanocassane-type diterpenes [caesalpinins C-G (1-5) and norcaesalpinins D and E (6, 7)] together with norcaesalpinins A-C (8-10) and 11 known compounds (norcaesalpinins A-C, 2-acetoxy-3-deacetoxycaesaldekarin e, caesalmin B, caesaldekarin e, caesalpin F, 14(17)-dehydrocaesalpin F, 2-acetoxycaesaldekarin e, 7-acetoxybonducellpin C, and caesalmin G). Their structures were determined on the basis of spectroscopic analysis. The isolated diterpenes showed significant dose-dependent inhibitory effects on Plasmodium falciparum FCR-3/A2 growth in vitro.