Biosynthesis.: Part 28.: Colchicine:: definition of intermediates between O-methylandrocymbine and colchicine and studies on speciosine
Biosynthesis.: Part 28.: Colchicine:: definition of intermediates between O-methylandrocymbine and colchicine and studies on speciosine
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DOI：
10.1039/a803851a
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发表时间：
1998-09-21
期刊：
影响因子：
--
通讯作者：
Battersby, AR
中科院分区：
文献类型：
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作者：
Barker, AC;Julian, DR;Battersby, AR
标记的样品由去甲秋水仙碱3、秋水仙碱4、N-甲酰基-N-脱乙酰基秋水仙碱6和N-脱乙酰基秋水仙碱7制备，后者依赖于从秋水仙碱制备的新方法，这些化合物和特异性标记的秋水仙碱1的掺入实验支持途径2 --> 5 --> 3 --> 6 --> 7 --> 4作为秋水仙碱生物合成的末端序列，关键中间体O-甲基雄蕊红碱2与speciosine 14及其O-乙酰基衍生物15一起从秋水仙植物中分离，这三个都是首次从该植物中分离。Speciosine 14和N-甲基demecolcine 8在体内主要由demecolcine 3形成，而N-甲酰基demecolcine 5是demecolcine的前体，其N-甲酰基来源于autumnaline的C-3。保留2的乙胺桥的两个碳的环酚酮生物碱的这一发现对于未来关于扩环过程的立体化学工作是重要的。
Labelled samples are prepared of demecolcine 3, colchicine 4, N-formyl-N-deacetylcolchicine 6 and N-deacetylcolchicine 7, the last depending on a new method for its preparation from colchicine, Incorporation experiments with these compounds and with specifically labelled autumnaline 1 support the pathway 2 --> 5 --> 3 --> 6 --> 7 --> 4 as the terminal sequence for the biosynthesis of colchicine,The key intermediate O-methylandrocymbine 2 is isolated from Colchicum autumnale plants together with speciosine 14 and its O-acetyl derivative 15; all three are first isolations from this plant. Speciosine 14 and N-methyldemecolcine 8 are shown to be formed in vivo largely from demecolcine 3 whereas N-formyldemecolcine 5 is the precursor of demecolcine and its N-formyl group is derived from C-3 of autumnaline. This discovery of a tropolone alkaloid which retains both carbons of the ethanamine bridge of 2 is important for future stereochemical work on the ring-expansion process.