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Published on: July 19, 2019
Which is more likely in trichodiene biosynthesis: hydride or proton transfer?
Young J Hong1, Dean J Tantillo
1Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, USA.
Abstract:
The mechanisms proposed for enzyme-catalyzed formation of the sesquiterpene natural product trichodiene consistently include a step involving a 1,4-hydride transfer. Using quantum chemical methods (B3LYP/6-31+G(d,p) and mPW1PW91/6-31+G(d,p)), we discovered two alternative pathways for transformation of the intermediate bisabolyl cation to the cuprenyl cation, one of which--a proton-transfer pathway--appears to be much more energetically favorable (by more than 10 kcal/mol) than the hydride transfer pathways usually proposed.
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