| Summary: | 碩士 === 國立臺灣大學 === 藥學系 === 85 === The Bioactive Constituents of Drypetes hieranensis
In the course of biological activity screening，the ethanolic
extract of the leaves of Drypetes hieranensis Hay.(
Euphobiaceous )，exhibited inhibitory effect against EBV-
DNA polymerase．Hence, this study was aimed to study the
boactive ingredients of this plant. The ethanolic extract of
the leaves was divided into fractions soluble in chloroform,
ethyl acetate， n-butanol and H2O by liquid-liquid
partitioning. The chloroform soluble fraction was
repeatedly chromatographed on silica gel columns to give
compounds ( 12 ) ~ (17 ) and ( 9 )．Separation of the ethyl
acetate and n-butanol soluble fractions over Sephadex LH-20
，centrifugal partition chromatography ( C.P.C. )，and
Toyoperal HW-40C columns afforded compounds ( 1 ) ~ ( 8 ) and
( 10 )~( 11 )．The structural elucidation of these
compounds was conducted mainly by spectroscopic analysis.
According to properties of the structures, they were
classified into five categories: 1. Biflavones:
podocarpusflavone A ( 1 ), amentoflavone ( 2 )
2. Polyphenolic compounds:
ethyl brevifolin carboxylate ( 3 ), ethyl gallate ( 4 )
ellagic acid ( 5 ), ellagic acid 4-O-α-L-rhamnoside ( 6 ),
ellagic acid 4-O-β-D-xyloside ( 7 ), 3,3-O,O-
dimethylellagic acid 4-O-α-L- rhamnoside ( 8 ),
hexamethylcoruleoellagic acid ( 9 ). 3.
Tannins:
corilagin ( 10 ), geraniin ( 11 )
4. Sterols:
β-sitosterol / stigmasterol ( 12 ), β-sitosterol 3-β-D-
glucoside / stigmasterol 3-β-D-glucoside ( 13 ).
5. Triterpenes:
squalene (14), 3-oxofriefelan-30-ol (15), 3β,30-
dihydroxyfriedelane (16)
Among compounds isolated from ethyl acetate and n-butanol，
componds (2) 、( 5 )、( 10 ) and (11) show anti-HIV-1 reverse
transcriptase activity with the IC50 of 17.6, 21.9, 33.8 and
17.5μM respectively；besides，compounds (10)and ( 11 ) also
showed anti-EBV DNA polymerase activity at IC50 29.0 and 27.1 μ
M respectively．
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