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1.
Jack C. Kim 《Archives of pharmacal research》1994,17(3):204-206
A regioselective preparation of 10-methoxy-11-hydroxyaporphine (“Apocodeine,1b”) from (R,S)-10, 11-dihydroxyaporphine(apomorphine,1a) is described. The isopropylidene ketal ring of 10,11-(isopropylidenyldioxy) aporphine (2) obtained by the isopropylidenation of apomorphine, was regioselectively opened by the ten equivalent of trimethylaluminum
to give 10-hydroxy-11-t-butyloxyaporphine (3). The free 10-hydroxyl position of 3 was methylated with methyl p-toluenesulfonate/NaH, and afforded 10-methoxy-11-t-butyloxyaporphine
(4) in high yield. Selective debutylation gave the desired 10-methoxy-11-hydroxyaporphine (“apocodeine”,1b) in good yield. 相似文献
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目的 研究四逆汤中乌头类生物碱的溶出平衡和水解平衡。方法 利用电喷雾质谱分析,比较了制附子、四逆汤、四逆汤药渣和含有3种双酯型生物碱的混合对照品体系中的乌头碱类二萜生物碱。结果 在煎煮过程中双酯型生物碱溶解并发生水解反应,而脂类生物碱则难溶于水。乌头碱、中乌头碱、次乌头碱水溶性相近,但是次乌头碱在水中的热稳定性更高,C19二萜骨架上C3取代基(—OH或—H)的变化影响生物碱的稳定性。结论四逆汤中的乌头碱类生物碱的种类及含量由其溶解性和化学稳定性共同决定。 相似文献
5.
Ghosal Shibnath Shanthy Amirthalingam Mukhopadhyay Mita Sarkar Mihir K. Das Prasun K. 《Pharmaceutical research》1986,3(4):240-243
The effect of lycoriside, an acylglucosyloxy alkaloid from Crinum asiaticum Linn, (family Amaryllidaceae), with or without sitosterol-3-O--D-glucoside, was studied on the rate of degranulation of peritoneal mast cells of albino rats. Lycoriside, at lower concentrations (1–20 µg/ml), in vitro, produced statistically significant protection against Tween 80-induced degranulation, as also to sensitized mast cells challenged with an antigen (horse serum). It also provided protection against compound 48/80-induced degranulation of mast cells when administered in vivo (1–5 mg/kg, po). At higher concentrations (100 µg/ml and above), in vitro, however, it had a mast-cell degranulation effect per se. The addition of sitosterol-3-O--D-glucoside to lycoriside did not modify the effect of the latter compound. The mechanism of the dual response elicited by lycoriside is appraised in view of a concentration-dependent anti- or prerelease effect on mast-cell mediators. 相似文献
6.
A rapid assay is described for the simultaneous determination of emetine and cephaeline in ipecacuanha and its preparations, based upon the different fluorescence intensities of the alkaloids at pH 1 and pH 12. The assay involves the measurement of fluorescence at 317 nm of dilutions of the sample in 0.1 M hydrochloric acid (pH 1) and 0.01 M sodium hydroxide (pH 12) with an excitation wavelength of 283 nm. Concentrations of the individual alkaloids are calculated using two simultaneous equations derived from the experimentally determined coefficients of fluorescence of solutions (1 μg/ml) of emetine and cephaeline at pH 1 and pH 12. The procedure, which has been shown to be accurate, precise and sensitive, requires only 1 ml of a liquid sample and less than 0.5 g of powdered root. There was reasonable agreement between the total concentrations of alkaloids in tinctures and liquid extracts of ipecacuanha determined by the spectrofluorimetric method and by the titrimetric procedure of the British Pharmacopoeia. The fluorimetric procedure gave higher levels of alkaloids in the powdered root than did the B.P. method; this difference is explained by incomplete extraction of the alkaloids in the B.P. procedure for powdered ipecacuanha root. 相似文献
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Reversible hepatic veno-occlusive disease in an infant after consumption of pyrrolizidine-containing herbal tea 总被引:1,自引:0,他引:1
W. Sperl H. Stuppner I. Gassner W. Judmaier O. Dietze W. Vogel 《European journal of pediatrics》1995,154(2):112-116
Veno-occlusive disease was diagnosed in an 18-month-old boy who had regularly consumed a herbal tea mixture since the 3rd month of life. The boy developed portal hypertension with severe ascites. Histology of the liver showed centrilobular sinusoidal congestion with perivenular bleeding and parenchymal necrosis without cirrhosis. The tea contained peppermint and what the mother thought was coltsfoot (Tussilago farfara). The parents believed the tea aided the healthy development of their child. Pharmacological analysis of the tea compounds revealed high amounts of pyrrolizidine alkaloids. Seneciphylline and the corresponding N-oxide were identified as the major components by thin-layer chromatography, mass spectrometry and NMR spectroscopy. We calculated that the child had consumed at least 60 g/kg body weight per day of the toxic pyrrolizidine alkaloid mixture over 15 months. Macroscopic and microscopic analysis of the leaf material indicated thatAdenostyles alliariae (Alpendost) had been erroneously gathered by the parents in place of coltsfoot. The two plants can easily be confused especially after the flowering period. The child was given conservative treatment only and recovered completely within 2 months. 相似文献
9.
石蒜科生物碱的研究Ⅻ-薄层色谱鉴别石蒜生物碱和高效液相色谱法测定加兰他敏的含量 总被引:7,自引:1,他引:6
目的: 研究分离鉴别石蒜科生物碱加兰他敏和力可拉敏( 二氢加兰他敏) 及加兰他敏含量测定的方法。方法: 采用硅胶薄层色谱分离鉴别石蒜生物碱, 以二氯甲烷- 甲醇- 氨水(90∶10∶0-5)展开, 稀碘化铋钾试剂显色; 高效液相色谱法采用硅胶柱, 流动相为二氯甲烷- 甲醇(100∶8) , 检测波长为254 nm , 线性范围为80 ~320 μg , r = 0-999 6 。结果: 硅胶薄层色谱可分离鉴别石蒜生物碱加兰他敏和力可拉敏, 硅胶柱高效液相色谱法分离加兰他敏和力可拉敏及测定加兰他敏的含量, 分离效果好, 定量准确。结论: 本法简便快速, 定量准确。在原料药和制剂的分析中有推广价值。 相似文献
10.
本文从中药黄藤的根及根茎中分得三种季铵生物碱,化学及光谱数据证明,一为掌叶防己碱(巴马汀),二为药根碱,三系伪非洲防己胺碱。后者为国内首次得到的一种天然伪原小檗碱型生物碱。 相似文献