Total synthesis of the spermidine alkaloid (+)-(9S,13S)-isocyclocelabenzine

Article abstract of DOI:10.1016/0040-4020(96)00872-1

An asymmetric synthesis of the spermidine alkaliod (+)-isocyclocelabenzine (1a) is reported using (3S)-3-amino-3-phenylpropanoic acid as the chiral building block. The 1,2,3,4-tetrahydroisoquinolin-1-one fragment 9 was synthesized by a modified Bischler-Napieralski reaction. The resulting C(13)-epimers were separated by semi-preparative HPLC. The relative configuratoin of the naturally occurring alkaloid was determined by an X-ray crystal structure analysis, which enabled us to determine the absolute configuration of natural (+)-1a at both chiral centers to be (9S) and (13S).