Prodn. of eserolin and bromeserolin - by redn. (with organo-metallic) or bromination of hydroxy-tri:methyl- tetra:hydro:pyrrole(2, 3-b) indolone, opt. after resolution with chiral isocyanate

摘要

The following processes are claimed: (A) Prodn. of(+-)-1,3a,8-trimethyl-3,3a,8,8a- tetrahydropyrrolo(2, 3-b) -indol-5-ol (II) comprises reducing 5-hydroxy-1,3a,8-trimethyl- 3,3a,8,8a-tetrahydro- pyrrolo(2, 3-b) -indol-2-one (I) using an organometallic reducing agent (A). (B) Prodn. of (+-)-7-bromo-5-hydroxy-1,3a,8- trimethyl-3,3a,8,8a-tetrahydro- pyrrolo(2, 3-b) -indol-2-one (III) by brominating (I). (C) Prodn. of (+-)-7-bromo-5-hydroxy-1,3a,8- trimethyl-3,3a,8,8a- tetrahydropyrrolo(2, 3-b) -indol-5-ol (IV) by reducing (III) with (A); and (D) Prodn. of (+) and (-) isomers of (I) by separating racemic (I) into diastereomers, using a chiral isocyanate and a catalyst; sepg. the diastereomers by crystallisation, and splitting them with a bath. Also claimed is the use of the pure isomers of (I) for prodn. of optically active (II), (IV), physostigmine (eserin) and derivs. of these.