Flavonoid glycosides from the nectar of Camellia reticulata Lindl

The nectar of Camellia reticulata Lindl. contains sugar, amino acids and other nutritional components, suggesting that it could be developed for food and food additives. To understand the effects of the nectar on human health, we investigated its chemical constituents. Two new flavonoid glycosides, cameretiins A and B (1 and 2), and two known flavonoid glycosides, kaempferol 3-O-(2''-O-E-p-coumaroyl)-β-D-glucopyranoside (3) and tiliroside (4) were obtained from the nectar of Camellia reticulata Lindl. Their structures were determined based on analysis of their spectroscopic data and by comparison with 1D NMR spectroscopic data of known compounds reported in the literature. Compounds (1-4) were first isolated from the nectar of Camellia reticulata Lindl.

Keywords: Camellia reticulata Lindl.; Nectar; flavonoid glycosides; tyrosinase inhibitory activity.