ABSTRACT
Objective: To study the chemical constituents from the medicinal herb of Caesalpinia decapetala. Methods: Silica gel and Sephadex LH-20 column chromatography techniques were used as pretreatments for ethanol extract of the seeds of C. decapetala, and then semi-preparative HPLC technique was used. Results: Eight cassane diterpenes were isolated from the chloroform extract of C. decapetala. According to NMR, ESI-MS, and CD spectrum data, they were identified as 1α,6α,7β-triacetoxy-14α-methoxy- vouacapen-5α-ol (1), caesalmin F (2), neocaaesalpin MP (3), 1-deacteoxy-1-oxocaesalmin C (4), neocaesalpin AA (5), bonducellpin C (6), bonducellpin E (7), and neocaaesalpin N (8). Conclusion: Compound 1 is a new compound and named as caediterpene A, compound 1-2 are a pair of epimeric diterpenes, and compounds 3-7 are obtained for the first time from the seeds of C. decapetala.