3,6-Dioxoperhydropyrrolo[1,2-a]pyrazines. A new approach to conformationally restricted tripeptides

Article abstract of DOI:10.1016/0040-4039(92)88173-3

Catalytic hydrogenation of the 4-ketodiesters, obtained from Z-Xaa-Gly (Xaa = Ala, Phe) halomethyl ketones and dimethyl malonate, provides readily access to the corresponding 4-substituted-3,6-dioxoperhydropyrrolo[1,2-a]pyrazine-7-carboxylic acid derivati