Abstract

• The aim of this paper is to study the NMR spectroscopic characterization of seven triterpenes from Streptocaulon tomentosum Wight & Arnott (Asclepiadaceae). Four ursane type triterpenes and three oleanane type triterpenes were isolated from the roots of Streptocaulon tomentosum. by column chromatography and identified by NMR spectroscopy. Comparative studies on NMR spectra of ursane type and oleanane type triterpenes were done. Four ursane type triterpenes were identified as -amyrin acetate (compound 2),2,3,23-trihydroxy-urs-12-en-28-oic-acid (compound 3), 2,3- dihydroxy-urs-12-en-28-oic-acid (compound 4), and 2,3,23-trihydroxy-urs-12-en-28-oic-acid (compound 6). Three oleanane type triterpenes were identified as -amyrin acetate (compound 1), 2,3-dihydroxy-olean-12-en-28-oic-acid (compound 5) and 2,3,23-trihydroxy-olean-12-en-28- oic-acid (compound 7).