Piperlongosides A–C, Three New Phenolic Constituents From <i>Piper longum</i> L.

Phytochemical study on the methanolic extract of aerial parts this plant led to isolation 7 phenolic compounds (1-7), including 3 new ones (1-3). Their chemical structures were determined be (7,8- threo)-1 -O-β-D-[6′ -O-syringoylglucopyranosyl]-2-methoxy-7,8,9-trihydroxyphenylpropane (1), threo)-8 -O-(2′′-methoxyacetophenone-1′′-yl)-1 -O-β-D-glucopyranosyl-2-methoxy-7,9-dihydroxyphenylpropane (2), 1 -O-β-D-glucopyranosyl-2 -O-(2′′-methoxy-4′′-acetylphenyl)-3-hydroxypropane (3), (−)-isolariciresinol 4 -O-β-D-glucopyranoside (4), (−)-isolarisiresinol 9′ (5), (+ )-lyoniresinol (6), )-isolarisiresinol (7) by spectroscopic data and in comparison with those reported literature. Compounds significantly inhibited NO production LPS-activated RAW264.7 cells IC 50 values ranging from 32.09 ± 3.34 38.16 1.35 µM, similar positive control, N G -monomethyl-L-arginine acetate (IC 32.51 3.70 µM).