Abstract
On the basis of chemical and physicochemical evidence, the structures of four triterpenoidal oligoglycosides, bivittoside A, B, C, and D from the sea cucumber Bohadschia bivittata MITSUKURI, have been elucidated as 6, 8, 9, and 10, respectively. A new homoannular dienic sapogenol was isolated as the acetate and the highly strained structure (4a) has been elucidated.