SYNTHESIS OF MYRIMCARIN 217, A PYRROLO[2,1,5-CD]INDOLIZINE FROM ANTS

The ant alkaloid myrmicarin 217 ,7-hexahydro-2-propylpyrrolo-[2,1,5-cd ]indolizine, 1) was synthesized using a new method for the direct cycl ization of appropriately disubstituted piperidines. The mechanism for the formation of the pyrrolo[2,1,5-cd]indolizine system was investigat ed by H-1-NMR spectroscopy, which showed the reaction to proceed throu gh indolizidine intermediates. The course of this facile cyclization m ay parallel steps in the biosynthesis of mymicarin 217 and related alk aloids. (C) 1998 Elsevier Science Ltd. All rights reserved.