Untitled

Antioxidative Compounds from Marine Organisms

“…Comprehensive ^-NMR analysis (Table I) revealed that 2 has a similar structure to that of 1. In the HMBC spectrum of 2, prominent crosspeaks from H-17 2b/ to C-13 2 and C-17 3 and H-17 2b to C-17 3 were observed. These observations revealed that C-13 2 and C-17 3 are within a three bond proximity to H-17 2b and H-17 2b '.…”

“…In the HMBC spectrum of 2, prominent crosspeaks from H-17 2b/ to C-13 2 and C-17 3 and H-17 2b to C-17 3 were observed. These observations revealed that C-13 2 and C-17 3 are within a three bond proximity to H-17 2b and H-17 2b '. Thus 2, name chlorophyllonelactone a, has a structure in which ring V of 1 has been converted to a δ-lactone (17,18 Concentration: *, 1 mg/0.6 ml; **, 0.6 mg/0.6 ml.…”

“…and the brown alga Undaria pinnatifida showed potent antioxidative activity in the conventional test (3). They identified pheophytin a, one of the degradative products of chlorophyll a, as an active principle (4). Fujimoto et al also screened 21 species of marine algal extracts for antioxidants and reported that more than half of them exhibited antioxidant activity to some extent.…”

“…and the brown alga Undaria pinnatifida showed potent antioxidative activity in the conventional test (3). They identified pheophytin a, one of the degradative products of chlorophyll a, as an active principle (4).…”