Facile orthoester formation in a model compound of the taxol oxetane: Are biologically active epoxy esters, orthoesters, and oxetanyl esters latent electrophiles?
Facile orthoester formation in a model compound of the taxol oxetane: Are biologically active epoxy esters, orthoesters, and oxetanyl esters latent electrophiles?
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DOI：
10.1002/hlca.200390306
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发表时间：
2003-01-01
影响因子：
1.8
通讯作者：
Faraldos, JA
中科院分区：
文献类型：
--
作者：
Giner, JL;Faraldos, JA
作为紫杉醇氧杂环丁烷的仿生模型，通过八个步骤合成了甾体氧杂环丁酯。该模型化合物在酸性条件下具有令人惊讶的反应性，在没有水的情况下重排为[2.2.1]-双环原酸酯。氧杂环丁基酯和原酸酯都容易水解产生相同的三醇单乙酸酯。在氧杂环丁基酯/原酸酯重排的基础上，紫杉烷中的环氧酯和氧杂环丁基酯被提出了一种新的生化功能，由此这些官能团产生的二氧鎓离子与细胞蛋白质反应形成混合原酸酯或醚。类似的过程可能涉及天然原酸酯（例如树脂毒素）的作用机制。
A steroidal oxetanyl ester was synthesized in eight steps as a biomimetic model of taxol oxetane. The model compound was surprisingly reactive under acidic conditions, rearranging in the absence of H2O to a [2.2.1]-bicyclic orthoester. Both the oxetanyl ester and the orthoester readily hydrolyze to produce the same triol monoacetate. On the basis of the oxetanyl ester/orthoester rearrangement, a novel biochemical function is suggested for the epoxy esters and oxetanyl esters found in taxoids whereby dioxonium ions, generated from these functional groups, react with cellular proteins to form mixed orthoesters or ethers. A similar process could be involved in the mechanism of action of natural orthoesters such as resiniferatoxin.