作者:Alma Sanchez-Eleuterio、Virginia M. Mastranzo、Leticia Quintero、Fernando Sartillo-Piscil
DOI:10.2174/1570178614666170307091943
日期:2017.6.8
Background: The synthesis of biologically active model compounds represents a valuable
tool for medicinal chemistry. In this regard, the synthesis of MSVII-19, a structurally simplified model
compound of Dysiherbaine, developed by the group of Sasaki, was synthesized with the intention of
preparing a powerful agonist or antagonist of glutamate receptor. Therefore, the synthesis of an advanced
intermediate in the Sasaki’s synthesis of MSVIII-19 is reported.
Methods: Taking advantage of the furanose ring of the diacetone-D-glucose (DAG), the cis-fused
hexahydrofuro[3,2-b]pyran ring system of the title compound was constructed by featuring two protocols:
SHOWO (sequential hydrolysis-oxidation-Wittig olefination) and RCM (ring closing metathesis).
Then, by applying a combined allylation at the anomeric position and a Pd-catalyzed double bond
isomerization reaction, the methyl ester group in 1b was installed.
Results: The synthesis of an advanced intermediate of MSVIII-19 involves three key procedures: a)
SHOWO (sequential hydrolysis-oxidation-Wittig olefination) protocol; b) RCM (ring closing metathesis)
reaction; y c) the nucleophilic substitution at the anomeric position. Additionally, with the use of a
cheaper starting material (DAG) than that used in the previous synthesis (tri-O-acetyl-D-glucal). The
current synthesis is truly competitive with that reported by the Sasaki group.
Conclusion: A concise formal total synthesis of the advanced intermediate of MSVIII-19 was
achieved. (Current synthesis: 14 steps; previous synthesis 20 steps).
背景:生物活性模型化合物的合成是药物化学中的一项重要工具。在这方面,由佐佐木团队开发的结构简化的Dysiherbaine模型化合物MSVIII-19的合成旨在制备强效的谷氨酸受体激动剂或拮抗剂。因此,报告了佐佐木合成MSVIII-19中一个高级中间体的合成。
方法:利用二乙酮-D-葡萄糖(DAG)的呋喃环,通过两个步骤构建了标题化合物的顺式融合六氢呋喃[3,2-b]吡喃环系统:SHOWO(顺序水解-氧化-Wittig烯化)和RCM(环闭合烯烃交换反应)。然后,通过在异头位置应用联合烯丙基化和Pd催化的双键异构化反应,以安装1b中的甲基酯基团。
结果:MSVIII-19高级中间体的合成涉及三个关键程序:a) SHOWO(顺序水解-氧化-Wittig烯化)协议;b) RCM(环闭合烯烃交换)反应;c) 在异头位置的亲核取代。此外,使用了比先前合成中使用的起始材料(tri-O-乙酰-D-葡萄糖醛)更便宜的起始物质(DAG)。目前的合成与佐佐木团队报告的合成相比,具有较强的竞争力。
结论:成功实现了MSVIII-19高级中间体的简洁正式总合成。(当前合成:14步;先前合成:20步)。