Synthesis of fire ant venom alkaloids, dehydrosolenopsins B & C

Piperidine alkaloids are the major constituents of the venom of the imported fire ant, Solenopsis invicta . Even though the alkaloid fraction is mainly comprised of (2 R ,6 R )- trans -2-methyl-6-alky- and 6- alkenylpiperidines small amounts of (2 R ,6 S )-cis-analogs are also present. Several procedures have been reported for the stereospecific synthesis of (2 R ,6 S )- cis - and (2 R ,6 R )- trans -2-methyl-6-alkylpiperidine constituents. However, no procedure has so far been reported for the stereospecific synthesis of (2 R ,6 R )- trans -2-methyl-6-alkenylpiperidine constituents. We have developed a procedure for the stereospecific synthesis of the major (2 R ,6 R )- trans -2-methyl-6-alkenylpiperidine fire ant venom alkaloids, (2 R ,6 R )-dehydrosolenopsin B and C.