Three New Pentasaccharide Resin Glycosides from the Roots of Sweet Potato (Ipomoea batatas)

Abstract

Three new pentasaccharide resin glycosides, batatosides III—V (1—3), were isolated from the roots of Sweet potato (Ipomoea batatas). Saponification of the crude resin glycoside mixture yielded substituents and simonic acid B. The structures of the isolated compounds (1—3) were established through spectroscopic analyses, including high field NMR spectroscopy and HR-ESI-MS, and chemical correlation. The major characteristics of 3 are the presence of three different substituents, especially the substituent of cinnamic acid was seldom. The monosaccharides of 1—3 were proved by GC-MS and the absolute configuration of aglycone was further established as S by Mosher's method with R-methyloxyphenylacetic acid (MPA) and S-MPA.