Novel synthesis of 5,11‐dihydro‐6H‐pyrido[2,3‐b]‐[1,4]benzodiazepin‐6‐ones and related studies

Publisher Website
Google Scholar
Abstract
5,11‐Dihydro‐6H‐pyrido[2,3‐6][1,4]benzodiazepin‐6‐one (1), a basic intermediate in the preparation of 11‐α‐aminoacetyl derivatives with important biological activities, has been obtained by a three‐step synthesis starting from easily available isatoic anhydride and anhydro ornithine. Some model cyclisation reactions leading to 5‐member ring derivatives 10 and 12 instead of 7‐member ring analogues of 1, are reported. Easy transformations of the tetrahydro congener of 1, i.e., compound 4 into 19, which actually represents a tetrahedral intermediate in the transformation of 5 into 4, is noticed. Further rearrangement of 19 into spiro compound 20, and return of the latter into 5 is described.