Enanatiomerically pure 4aS,7S,7aR and 4aS,7S,7aS-nepetalactams and their analogs have been prepared in just two steps from 4aS,7S,7aR and 4aS,7S,7aS-nepetalactones, major components of catnip oil. Lactams or cyclic amides from iridoid monoterpenes are generated and being evaluated as a new class of compounds as arthropod deterrents against disease vectors.
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5.
(a) ChauhanK.R., ZhangA. (2008) Methods of separating ZE-nepetalactone and EZ-nepetalactone from catnip oil. U.S. Patent 7,375,239 B2; (b) Birkett MA, Pickett JA. (2003) Aphid sex pheromones: from discovery to commercial production. Phytochemistry, 62, 651–656.
(a) DawsonG.W., PickettJ.A., SmileyW.M. (1996) The aphid sex pheromone cyclopentanoids: Synthesis in the elucidation of structure and biosynthetic pathways. Bioorganic & Medicinal Chemistry, 4, 351–361;(b) Since nepetalactam isomers were derived from nepetalactone 3 and 4, the absolute configuration remain intact for 7a, 7 and 4a positions of origin (which was established earlier [7a]).
(a) ScialdoneM.A. (2006) Derivatives of dihydronepetalactone and methods of preparation. U.S. Patent 7,067,678 B2; (b) Scialdone MA, Liauw A. (2006) Nepetalactam and N-substituted derivatives thereof. U.S. Patent 20060148842 A1.
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