Mimicry of Peptide Backbone Geometry and Heteroatomic Side-Chain Functionality: Synthesis of Enantiopure Indolizidin-2-one Amino Acids Possessing Alcohol, Acid, and Azide Functional Groups
作者:Felix Polyak、William D. Lubell
DOI:10.1021/jo001251t
日期:2001.2.1
and 8, and indolizidin-2-one amino dicarboxylate 9. Both 5- and 7-hydroxymethylindolizidinone amino acids 5 and 6 were obtained from sequences commencing with the Claisen condensation of alpha-tert-butyl gamma-methyl l-N-(PhF)-L-glutamate to furnish di-tert-butyl 4-carbomethoxy-5-oxo-2,8-di-[N-(PhF)amino]azelate 10 (PhF = 9-(9-phenylfluorenyl)). Subsequent hydride reduction of 10 to an isomeric mixture
通过修饰羟甲基吲哚啶酮酮氨基酸5和6,合成了在5和7位具有各种杂原子侧链的吲哚嗪酮氨基酸。用叠氮化钠置换醇5和6中的甲磺酸盐,以及氧化乙醇5 ,已经被用于提供正交保护的吲哚并丁-2-一二氨基羧酸盐7和8,以及吲哚并嗪-2-一二氨基氨基羧酸9。5-和7-羟甲基吲哚嗪酮酮氨基酸5和6均从克莱森缩合反应开始的序列中获得。 α-叔丁基γ-甲基lN-(PhF)-L-谷氨酸制备4-羧甲氧基-5-氧代-2,8-二-[N-(PhF)氨基]壬二酸二叔丁基酯10( PhF = 9-(9-苯基芴基)。随后将氢化物还原10为二醇12的异构体混合物 伯醇作为叔丁基二甲基甲硅烷基醚14的选择性保护和仲醇的氧化产生了4-叔丁基二甲基甲硅烷基氧基甲基-5-氧代-2,8-二-[N-(PhF)氨基]壬二酸酯的二叔丁基作为可分离的非对映异构体混合物。然后通过具有还原性胺化,甲磺酸盐置换和内酰胺环化的路线将直链酮15和醇14转化