The present study investigated the chemical constituents of Caesalpinia decapetala in the Fabaceae family. The chemical constituents were isolated and purified by chromatographies with silica gel, RP-C_(18), Sephadex LH-20, and preparative HPLC, and their structures were determined based on the spectroscopic data and physicochemical properties, as well as relevant references. Three pairs of new dibenzoxocin derivatives were isolated from 70% ethanol extract of C. decapetala and identified as protosappanoside A(1 a), isoprotosappanoside A(1 b), protosappanoside B(2 a), isoprotosappanoside B(2 b), protosappanoside C(3 a), and isoprotosappanoside C(3 b), respectively.
Keywords: Caesalpinia decapetala; Fabaceae; chemical structure determination; dibenzoxocin derivatives.