Bioactive saponins and glycosides. XXIII. Triterpene saponins with gastroprotective effect from the seeds of Camellia sinensis–theasaponins E3, E4, E5, E6, and E7. - Yoshikawa,M.; Morikawa,T.; Li,N.; Nagatomo,A.; Li,X.; Matsuda,H. (Chem Pharm Bull, 2005)