A novel and efficient two-step synthetic sequence for the preparation of 3,3-disubstituted oxindoles was developed starting from arylhydrazines and α-branched aldehydes via Fischer indole type synthesis followed by imine oxidation.
A series of 15 benzene-fused hexahydropyrrolo[1,2-b]isoquinolonic acids with substantial degree of steric encumbrance has been prepared via a novel variant of the Castagnoli-Cushman reaction of homophthalic anhydride (HPA) and various indolenines. The employment of a special kind of a cyclic imine component reaction allowed, for the first time, isolating a Mannich-type adduct between HPA and an imine
Sterically Constrained and Encumbered: An Approach to the Naturally Occurring Peptidomimetic Tetrahydropyrazino[1,2-<i>a</i>]indole-1,4-dione Core
作者:Pavel Golubev、Mikhail Krasavin
DOI:10.1002/ejoc.201700152
日期:2017.4.3
The combination of two privileged motifs, that is, indoline and the constrainedpeptidomimetic piperazine-2,5-dione, within one tricyclic structure resulted in a scaffold that is abundant in nature but surprisingly scarce in the domain of synthetic bioactive molecules. Utilizing the power of the isocyanide-based Joullie–Ugi reaction followed by postcondensation cyclization, we synthesized such compounds