Abstract Continuing our systematic 15 N NMR study of isoquinoline alkaloids, we report a contribution extending our previous paper. The 15 N NMR chemical shifts and 15 N, 1 H long-range coupling pathways of tertiary and quaternary isoquinoline alkaloids of several constitutional types are presented. The selected compounds belong to the protoberberine, proaporphine, pavinane, rhoeadine and phtalideisoquinoline classes of alkaloids and ...
