Asymmetric Synthesis of 4′-epi-Trachycladines A and B.
Asymmetric Synthesis of 4′-epi-Trachycladines A and B.
复制标题
4-表-Trachycladines A 和 B 的不对称合成。
DOI：
10.1002/chin.200618205
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
Eugen Drosdow
中科院分区：
文献类型：
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作者：
D. Enders;Irene Breuer;Eugen Drosdow
首次报道了4′-表粗环内酯A和B的不对称合成。以2，2-二甲基-1，3-二氧六环-5-酮为起始原料，采用SAMP-/RAMP-腙法经14步合成了标题核苷。二氧环己酮-SAMP-腙首先通过三重α-/α′-烷基化反应转化为三取代衍生物。除去手性助剂，还原得到相应的醇，经四步反应得到TBS保护的2′-C-甲基-5 ′-脱氧-1-来苏糖。然后使用标准Vorbrüggen和甲硅烷基-Hilbert-约翰逊条件通过相应的三乙酸酯以18- 21%的总产率获得粗环戊烯。这类2′-C-分支的核糖核苷是腺苷受体的潜在激动剂，在药物发现中起着重要作用。
The first asymmetric synthesis of 4′-epi-trachycladines A and B is reported. Starting from 2, 2-dimethyl-1, 3-dioxan-5-one the title nucleosides were synthesised in 14 steps employing the SAMP-/RAMP-hydrazone methodology. The dioxanone-SAMP-hydrazone was first transformed into a trisubstituted derivative by a triple α-/α′-alkylation. Removal of the chiral auxiliary and subsequent reduction gave the corresponding alcohol, which could be transformed over four steps into TBS-protected 2′-C-methyl-5′-deoxy-l-lyxose. The trachycladines were then obtained via the corresponding triacetate using standard Vorbrüggen and silyl-Hilbert-Johnson conditions in an overall yield of 18-21%. Such 2′-C-branched ribonucleosides are potential agonists for adenosine receptors and play an important role in drug discovery.