Two new saponins, 3-O-[beta-D-glucuronopyranosyl-(1-->2)-beta-D-glucopyranosyl]hederagenin (named abrus-saponin I) and 3-O-[beta-D-glucuronopyranosyl-(1-->2)-beta-D-glucopyranosyl]oleanolic acid 28-beta-D-glucopyranosyI ester (abrus-saponin II), and three new flavones, 6-C-beta-D-glucopyranosyl-4',5-dihydroxy-7,8-dimethoxyflavone (precatorin I), 6-C-[beta-D-apiofuranosyl-(1-->2)-beta-D-glucopyranosyl]-4',5-dihydroxy-7,8-dimethoxyflavone (precatorin II), 6-C-[beta-D-apiofuranosyl-(1-->2)-beta-D-glucopyranosyl]4',5-dihydroxy-7-methoxyflavone (precatorin III), were isolated from the seeds of Abrus precatorius L. together with twelve known compounds including a naturally new saponin, 3-O-[beta-D-glucuronopyranosyl-(1-->2)-beta-D-glucopyranosyl]oleanolic acid. Their structures were determined on the basis of chemical and spectroscopic methods, In addition, the unusual NMR spectral behavior of the flavone C-glycosides is also discussed.
saponin, Leguminosae, Abrus precatorius, C-glycosyl flavone
Publication DOI: 10.1248/cpb.46.982Journal NLM ID: 0377775Publisher: Pharmaceutical Society Of Japan
Institutions: Research Institute for Wakan-Yaku, Toyama Medical and Pharmaceutical University, Toyama, Japan
Methods: 13C NMR, 1H NMR, methylation, IR, FAB-MS, acid hydrolysis, UV, extraction, optical rotation measurement, reversed-phase chromatography, HMBC, HMQC, COSY, HOHAHA, API-MS