Studies on the Constituents of the Stems ofTinospora tuberculata, IV. Isolation and Structure Elucidation of the Five New Furanoid Diterpene Glycosides Borapetoside C–G

Five new furanoid diterpene glycosides, named borapetoside C (1), D (2), E (3), F (4), and G (5), were isolated from the stems of Tinospora tuberculata Beumee (Menispermaceae). The structures of 1–5 were elucidated by chemical and spectroscopic methods.