Hetero-Diels–Alder and pyroglutamate approaches to (2S,4R)-2-methylamino-5-hydroxy-4-methylpentanoic acid
作者:James E. Tarver、Kristen M. Terranova、Madeleine M. Joullié
DOI:10.1016/j.tet.2004.08.089
日期:2004.11
protected (2S,4R)-2-methylamino-5-hydroxy-4-methylpentanoic acid, a non-coded amino acid of cyclomarin A, and its diastereomer are reported. A pyroglutamate template was employed in the key diastereoselective alkylation used for introducing the 4-methyl stereochemistry. In addition, the first diastereoselective intramolecular hetero-Diels–Alder of a 2-cyano-1-azadiene with an electron deficient dienophile
报道了完全保护的(2 S,4 R)-2-甲基氨基-5-羟基-4-甲基戊酸,环marin A的非编码氨基酸及其非对映异构体的立体选择性合成。在用于引入4-甲基立体化学的关键非对映选择性烷基化中使用焦谷氨酸模板。另外,描述了具有电子缺陷的亲双烯体的2-氰基-1-氮杂二烯的第一个非对映选择性分子内杂-Diels-Alder。