Phenolic Constituents from the Roots of Rosa taiwanensis Nakai (I)

Phytochemical investigation of the polyphenols present in the root of Rosa taiwanensis led to the isolation of fifteen compounds (1-15). These compounds were identified by their spectral data as well as by direct comparison with data in the literature and with authentic samples. Compound 1 was established as gallic acid 3-O-(6'-O-galloyl)-β-D-glucopyranoside (1). Compounds 2-6 were found to be hydrolyzable tannins possessing a glucose core: 1,6-di-O-galloyl-β-D-glucopyranose (2), strictinin (3), 2,3-(S)-HHDP-D-glucopyranose (4), 2,3-(S)-HHDP-6-O-galloyl-D-glucopyranose (5) and pedunculagin (6). Compounds 7-10 were condensed tannins: catechin (7), procyanidin B-1 (8), procyanidin B-3 (9) and procyanidin B-3 3-O-gallate (10). Compounds 11-13, all possessing an open-chain glucose group, were identified as casuarinin (11), casuariin (12) and punicacortein A (13). Compounds 14 and 15 were established as stenophyllinins A and B, respectively. These complex tannins (14 and 15) were isolated for the first time from a Rosaceae plant.