The Total Synthesis of Allosamidin. Expansions of the Methodology of Azaglycosylation Pursuant to the Total Synthesis of Allosamidin. A Surprising Enantiotopic Sense for a Lipase-Induced Deacetylation
作者:David A. Griffith、Samuel J. Danishefsky
DOI:10.1021/ja960526c
日期:1996.1.1
Allosamidin, recently isolated from mycelial extracts of Streptomyces sp. 1713, is a powerful and selective chitinase inhibitor. The total synthesis of allosamidin is described herein. The electric eel acetylcholinesterase-mediated enantioselective hydrolysis of (trans,trans)-2-(benzyloxy)cyclopentene-1,3-diol diacetate accessed a monoacetyl derivative. Five additional steps produced a protected version
Allosamidin,最近从 Streptomyces sp. 的菌丝体提取物中分离出来。1713,是一种强效选择性几丁质酶抑制剂。Allosamidin 的全合成在此描述。电鳗乙酰胆碱酯酶介导的 (trans,trans)-2-(benzyloxy)cyclopentene-1,3-diol diacetate 的对映选择性水解获得了单乙酰衍生物。五个额外的步骤产生了受保护版本的异沙脒苷元(“allosamizoline”)部分。Allal 衍生物与苯磺酰胺在卤源存在下立体选择性地反应,得到 2β-halo-1α-sulfonamidohexose。用强碱处理该产物生成中间体 1,2-磺酰氮丙啶,其被保护的丙二醛衍生物捕获以提供二糖甘氨酸。重申该方案可以获得所需的三糖。脱保护后,完成了异沙脒的全合成。此外,该方法经过修改后,可以获得几种异氨基丁酸...