13C NMR Study of ginseng sapogenins and their related dammarane type triterpenes

In connection with structure studies on dammarane type triterpenes and their glycosides, assignments of 13C NMR signals of fifteen 20-hydroxy-dammarane derivatives including Ginseng sapogenins have been achieved by the aid of shift reagents and deuterated compounds. It has been found that the differences of the 17 C, 21 C and 22 C chemical shifts between pairs of C-20 epimers are remarkable especially in the case of 12β-hydroxy derivatives, being significant for the study of the C-20 stereochemistry.