Application of Remote Photocyclization with a Pair System of Phthalimide and Methylthio Groups. A Photochemical Synthesis of Cyclic Peptide Models

Abstract

Application of regioselective remote photocyclization of a pair system consisting of a phthalimide group and a methylthio group to a homologous series of N-substituted phthalimides (4 and 5) possessing a terminal sulfide function in the amide side chain was investigated. On irradiation, medium to large membered cyclic peptide-like compunds (6, 7 and 9), up to a thirty-eight membered ring product (6f), were synthesized in moderate yields.