New polyglucopyranosyl and polyarabinopyranosyl of fatty acid derivatives from the fruits of Lycium chinense and its antioxidant activity

Four new compounds 3,4-dihydroxy benzoic acid 3-octadecanoyl-4-O-alpha-L-arabinopyranosyl (2a -> 1b)-2a-O-alpha-L-arabinopyranosyl-(2b -> 1c)-2b-O-alpha-L-arabinopyranoside (1), 2,6,10-trimethyl-n-dodec-2-en-1-oyl-1-O-alpha-L-arabinopyranosyl-(2a -> b)-2a-O-alpha-L-arabinopyranosyl-(2b -> 1c)-2b-O-alpha-L-arabinopyranosyl-(2c -> 1d)-2c-O-alpha-L-arabinopyranosyl-(2d -> 1e)-2d-O-alpha-L-arabinopyranosyl-(2e -> 1f)-2e-O-alpha-L-arabinop yranosyl-(2f -> 1g)-2f-O-alpha-L-arabinopyranoside (2), n-docos-9,12-dienoyl-alpha-D-glucopyranosyl-(2a -> 1b)-2 a-O-alpha-D-glucopyranosyl-(2b -> 1c)-2b-O-alpha-D-glucopyranosyl-(2c -> 1d)-2c-O-alpha-D-glucopyranosyl-(2d -> 1e)-2d-O-alpha-D-glucopyranosyl-(2e -> 1f)-2e-O-alpha-D-glucopyranoside (3), beta-D-glucopyranosy1-(2a -> 1b)-2a-O-beta-L-arabinopyranosyl-(2b -> 1c)-2b-O-beta-L-arabinopyranosyl-(2c -> 1d)-2c-O-beta-L-arabinopyranosyl-(2d -> 1e)-2d-O-beta-L-arabinopyranosyl-(2e -> 1f)-2e-O-beta-L-arabinopyranoside (4) along with some know compounds, were isolated and identified from a methanol extract Lycium chinense fruits. Their structures were determined of the new compounds using one- and two-dimensional NMR spectroscopies in combination by IR. FAB/MS and HR-FAB/MS. The compounds 1-4 were investigated for the antioxidant potential using 1,1-dipheny1-2-picrylhydrazyl (DPPH) radical scavenging activity, reducing power and the phosphomolybdenum activity and the results demonstrate that the compounds (2 and 3) has potential as a natural antioxidant whereas the compound (4) exhibited moderate activity and the compound (1) exhibited weak antioxidant activity. (C) 2013 Elsevier Ltd. All rights reserved.