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1.
The volatile compounds obtained by hydro- and micro-distillation methods from crushed fruits of Heracleum sphondylium ssp. ternatum (Velen.) Brummitt were analyzed by GC/MS. Both distillation methods and analysis results were compared.  相似文献   
2.
A new angelol-type coumarin glucoside from Angelica pubescens   总被引:1,自引:0,他引:1  
A new angelol-type coumarin glucoside, 6-[(1R,2R)-1, 2-dihydroxy-3-β-D-glucosyloxy-3-methylbutyl]-7-methoxycoumarin, was isolated from the roots of Angelica pubescens. Its structure was elucidated on the basis of spectral analysis.  相似文献   
3.
HPLC法测定柴胡地上部分的黄酮苷元   总被引:1,自引:0,他引:1  
运用HPLC法测定青海不同产地4种柴胡地上部分的黄酮, 为柴胡药材的综合有效利用提供依据. 采用C18色谱柱以V(甲醇):V(0.1% H3PO4)=1:1为流动相, 流速1 mL/min, 检测波长360 nm. 青海产柴胡地上部分均含丰富的黄酮, 其中以秦岭柴胡黄酮质量分数最高, 槲皮素质量分数达到2.27%, 总黄酮质量分数大于6.50%. 本方法简便, 对黄酮的定量准确, 改变以往柴胡只使用地下部分而弃去地上部分的局面, 提高柴胡药材的有效利用率.  相似文献   
4.
Two novel intermolecular rearranged biiridoid glucosides, rapulasides A and B (1 and 2), have been isolated from the roots of Heracleum rapula. Their structures were identified by extensive spectral analysis especially different NMR techniques. NOESY experiment, with the help of Dreiding molecular model, was used to elucidate their relative stereochemistry. Both compounds were tested for their inhibitory effects on rabbit platelet aggregation induced by PAF, ADP, or AA, respectively. Only trends of inhibition were observed for them.  相似文献   
5.
A Lignan Glucoside from Bupleurum scorzonerifolium   总被引:2,自引:0,他引:2  
A new lignanoside, saikolignanoside A, was isolated from the roots of Bupleurum scorzonerifolium. Its structure was determined as 3-methoxy-4-hydroxy-5-[(8‘S) -3“-methoxy-4“-hydroxyphenylpropyl alcohol]-E-cinnamic alcohol-4-O-β-D-glucopyranoside by means of NMR and MS analysis, acid hydrolysis and optical data.  相似文献   
6.
Three new chalcones, 3′‐carboxymethyl‐4,2′‐dihydroxy‐4′‐methoxychalcone ( 1 ), (±)‐4,2′,4′‐trihydroxy‐3′‐[(3‐hydroxy‐2,2‐dimethyl‐6‐methylenecyclohexyl)methyl]chalcone ( 2 ), and 2′′‐hydroxyangelichalcone ( 3 ), were isolated from the aerial parts of Angelica keiskei (Umbelliferae) together with five known compounds, artocarmitin A ( 4 ), (+)‐cis‐(3′R,4′R)‐methylkhellactone ( 5 ), (?)‐trans‐(3′R,4′S)‐methylkhellactone ( 6 ), 3,4‐dihydroxanthotoxin ( 7 ), and (Z)‐p‐coumaryl alcohol ( 8 ). The known compounds 4  –  8 were identified from Akeiskei for the first time. The structures of 1  –  3 were elucidated by interpreting spectroscopic data including 1D‐ and 2D‐NMR.  相似文献   
7.
Bupleurum chinense DC. is a well-known and very important traditional chinese drug. It is often used to treat common cold with fever, alternating chill and fever, the feeling of fullness and oppression in the chest. However, little is reported about the chemical constituents. We have reported the isolation and elucidation of saponins and other compounds from the roots of Bupleurum chinense DC1. This paper deals with the structure elucidation of the new compound, Saikosaponin v-2(1).Saikosap…  相似文献   
8.
A thorough investigation of the ethyl acetate soluble fraction from a methanol extract of the resin of Ferula foetida has resulted in the isolation of a new sesquiterpene coumarin namely epi‐conferdione ( 1 ), along with four known compounds, colladonin ( 2 ), karatavicinol ( 3 ), 8‐acetoxy‐5‐hydroxyumbelliprenin ( 4 ), and asacoumarin ( 5 ). These structures were elucidated on the basis of extensive spectroscopic techniques, including 1D and 2D NMR spectroscopy. The absolute configuration of the new compound was established by circular dichroism (CD).  相似文献   
9.
A new dimeric psoralen-type furanocoumarin, notopterol-(18-O-20')-notopol (1), was isolated from Notopterygium incisum for the first time and its structure was elucidated by spectroscopic methods.  相似文献   
10.
Summary A liquid-solid chromatographic pre-fractionation of naturally occurring phthalides has been developed. The LSC was carried out on a column of silica applying a 1–50% gradient elution of diethyl ether (containing 2% methanol) in pentane. The enrichment in the fractions led to better possibilities for a gas chromatographic separation and isolation allowing further studies by spectroscopic methods. Ligustilide may easily isomerize during GC as a result of ageing of the column.  相似文献   
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