Acylated oleanane-type triterpene oligoglycosides from the flower buds of Camellia sinensis var. assamica

Eight new acylated oleanane-type triterpene oligoglycosides, floraassamsaponins I, II, III, IV, V, VI, VII, and VIII, were isolated from the flower buds of Camellia sinensis var. assamica. The chemical structures of new constituents were characterized on the basis of chemical and physicochemical evidence. In the present study, floraassamsaponins I and II with sugar moiety at 28-position were obtained from the flower buds of C. sinensis var. assamica. In the past, acylated triterpene oligoglycosides with sugar moiety at 28-position have not been isolated from the flower buds of Camellia sinensis var. sinensis. This finding is interesting from the perspective of chemotaxonomy of Camellia plants. In addition, acylated oleanane-type triterpene saponins significantly inhibited the aggregation of Aβ42. [Display omitted]