Novel Approach to the Zaragozic Acids. Enantioselective Total Synthesis of 6,7-Dideoxysqualestatin H5
作者:Satoru Naito、Maya Escobar、Philip R. Kym、Spiros Liras、Stephen F. Martin
DOI:10.1021/jo011157s
日期:2002.6.1
The total synthesis of 6,7-dideoxysqualestatin H5 (3) has been completed by a concise approach that features the stereoselective intramolecular vinylogous aldol reaction of the furoic ester 25a to give 30 or its trimethylsilyl ether derivative 34, which possess the requisite absolute stereochemistry at C(3)-C(5) of 3. Compound 34 was reduced to the saturated bislactone 39, and the C(1) side chain subunit
6,7-二脱氧角鲨烯抑制素H5(3)的总合成已通过一种简明的方法完成,该方法的特征是糠酸酯25a的立体选择性分子内乙烯基醛醇缩醛反应可生成30或其三甲基甲硅烷基醚衍生物34,该化合物具有必要的绝对立体化学结构。 C.(3)-C(5)为3。将化合物34还原为饱和双内酯39,并引入C(1)侧链亚基47,生成半缩醛48和相应的酮49的混合物。将该混合物与甲醇一起搅拌,发生缩酮化,得到50和螺环甲基乙缩醛51a,b的混合物。在50中氧化伯醇基团,然后对剩余的两个酯基进行皂化,得到3。