Studies on physiologically active substances in citrus fruit peel. Part XX. Structure and physiological activity of phenyl propanoid glycosides in lemon (Citrus limon Burm. f.) peel.

Abstract

We report here the difference between phenyl propanoid glycosides obtained from hot water and methanol extracts of lemon peel. Eight phenyl propanoid glycosides were isolated, and their structures were established by UV, MS, 1H-NMR and 13C-NMR spectroscopy, as well as by chemical evidence. They were coniferin (1), syringin (2), dehydrodiconiferyl alcohol-4-β-glucoside (3), citrusin A (4), citrusin B (5), citrusin C (6), methyl-3-(4-β-glucopyranosyl-3-methoxyphenyl)propionate (7) and methyl-3-{4-(6-O-α-glucopyranosyl-β-glucopyranosyl)-3-hydroxyphenyl}propionate(8). Compound 7, after intravenously injecting (0.5 mg/100 g of body weight) into stroke-prone spontaneously hypotensive rats (SHR-SP), was found to lower the blood pressure. Among these isolated compounds, 7 and 8 are new phenyl propanoid glycosides.