Studies on the Lignan Constituents of Phyllanthus urinaria L.

• Main Authors: Lien, Yu-Chin, 連育青
• Other Authors: Russel Rhei-Long Chen
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/96757918517086861752

碩士 === 國立臺灣大學 === 藥學系研究所 === 86 === Phyllanthus urinaria L.(葉下珠) ( Euphorbiaceae ), an annual plant,is a well known herb used as traditional medicine for liver protection,jaundice, hepatitis, dropsy etc. in Asian countries. A number of lignans isolated from p hyllanthus plants have been proved to possess cytotoxicityand biological activ ities. The finding of a series of lignans in addition tothe previously reporte d lignans, phyllanthin, hypophyllanthin and phyltetralin, in a preliminary tes t raised great interest to a more detailed study on this type constituents of this plant.The n-hexane and chloroform soluble fractions were obtained from th e water insoluble residue of the ethanol extract of Phyllanthus urinaria L.. A total of thirteen lignans were isolated from these two fractions by the use o f repeated column chromatography on Sephadex LH-20,aluminum oxide, silica gel and thin-layer chromatography. Their structures and stereochemistry were eluci dated according to the spectroscopic analysis and chemical correlation. They a re classified into four categories :1. Diarylbutane lignans :phyllanthin ( 1 ) , niranthin ( 2 ),( 2S, 3S )-1-( 3,4-dimethoxyphenyl )-4-( 3,4-methylenedioxyp henyl )-2,3-dimethoxymethylbutane ( 3 )2. Aryltetralin lignans :phyltetralin ( 4 ), hypophyllanthin ( 5 ), nirtetralin ( 6 ),( 1R, 2S, 3S )-1-( 3,4-methylen edioxyphenyl )-2,3-bismethoxymethyl-6,7-methylenedioxy-1,2,3,4-tetrahydronapht halene ( 7 ),lintetralin ( 8 ), isolintetralin ( 9 )3. Diarylbutyrolactone lig nans :heliobuphthalmin lactone ( 10 ),( 2S, 3S )-2-( 3,4-dimethoxybenzyl )-3-( 3,4-methylenedioxybenzyl )-γ- lactone ( 11 )4. Tetrahydrofuran lignans :( 7S , 8S, 7''R, 8''S )-7,7''-di( methylenedioxyphenyl )-8,8''-di-( methoxymethyl )-tet rahydrofuran ( 12 ), virgatusin ( 13 ). To our knowledge, compounds ( 3 ), ( 7 ), ( 11 ) and ( 12 ) are novel natural products.