The three-component reaction of 1,2,3,4-tetrahydroisoquinoline, isatins and 3-phenacylideneoxindoles in refluxing ethanol afforded dispiro[indoline-3,1′-pyrrolo[2,1-a]isoquinoline-3′,3′-indolines] (4a–4x) in good yields via 1,3-dipolar cycloaddition.
A regio- and diastereoselective synthesis of 2,3-dihydro-10b′H-spiro[indeno[1,2-b]quinoxaline-11,1′-pyrrolo[2,1-a]isoquinoline]-2′,3′-diylbis(phenylmethanone) derivatives containing four contiguous chiral stereocenters was achieved through 1,3-dipolar cycloaddition of isoquinolinium N-ylides in a one-pot three-component reaction. The desired products were obtained in short reaction times and in moderate to high yields (up to 92%) under relatively mild reaction conditions. The structure and relative stereochemistry of the desired product was confirmed by X-ray diffraction analysis.
An efficient stereoselective assembly strategy for the construction of pyrrolidin-2,3′-oxindole cis-fused phosphadihydrocoumarins was established. The process involves the condensation of O-vinylphosphonylated salicylaldehydes and 3-amino oxindoles followed by intermolecular cycloaddition with high diastereoselectivity and atom economy.
Diastereoselective synthesis of dispirooxindoles via [3+2] cycloaddition of azomethine ylides to 3-phenacylideneoxindoles and evaluation of their cytotoxicity
