Traversing Biosynthetic Carbocation Landscapes in the Total Synthesis of Andrastin and Terretonin Meroterpenes
Dr. Gong Xu
Department of Chemistry, University of California, Berkeley, 826 Latimer Hall, Berkeley, CA, 94720 USA
Search for more papers by this authorMasha Elkin
Department of Chemistry, Yale University, 275 Prospect Street, New Haven, CT, 06520 USA
Search for more papers by this authorProf. Dr. Dean J. Tantillo
Department of Chemistry, University of California, Davis, 1 Shields Avenue, Davis, CA, 95616 USA
Search for more papers by this authorCorresponding Author
Prof. Dr. Timothy R. Newhouse
Department of Chemistry, Yale University, 275 Prospect Street, New Haven, CT, 06520 USA
Search for more papers by this authorCorresponding Author
Prof. Dr. Thomas J. Maimone
Department of Chemistry, University of California, Berkeley, 826 Latimer Hall, Berkeley, CA, 94720 USA
Search for more papers by this authorDr. Gong Xu
Department of Chemistry, University of California, Berkeley, 826 Latimer Hall, Berkeley, CA, 94720 USA
Search for more papers by this authorMasha Elkin
Department of Chemistry, Yale University, 275 Prospect Street, New Haven, CT, 06520 USA
Search for more papers by this authorProf. Dr. Dean J. Tantillo
Department of Chemistry, University of California, Davis, 1 Shields Avenue, Davis, CA, 95616 USA
Search for more papers by this authorCorresponding Author
Prof. Dr. Timothy R. Newhouse
Department of Chemistry, Yale University, 275 Prospect Street, New Haven, CT, 06520 USA
Search for more papers by this authorCorresponding Author
Prof. Dr. Thomas J. Maimone
Department of Chemistry, University of California, Berkeley, 826 Latimer Hall, Berkeley, CA, 94720 USA
Search for more papers by this authorGraphical Abstract
All positives: A key point of divergence in dimethylorsellinic-acid-derived meroterpene biosynthesis is the protoaustinoid A carbocation, which can be diverted to either the berkeleyone, andrastin, or terretonin structural classes by cyclase-controlled rearrangements. Shown herein is that the carbocation can be reverted to either andrastin or terretonin ring systems under abiotic reaction conditions. The first total syntheses of members of these natural product families are reported as their racemates.
Abstract
Meroterpenes derived from dimethylorsellinic acid (DMOA) and farnesyl pyrophosphate have attracted much biosynthetic attention, yet only recently have synthetic solutions to any family members appeared. A key point of divergence in DMOA-derived meroterpene biosynthesis is the protoaustinoid A carbocation, which can be diverted to either the berkeleyone, andrastin, or terretonin structural classes by cyclase-controlled rearrangement pathways. Shown herein is that the protoaustinoid bicyclo[3.3.1]nonane nucleus can be reverted to either andrastin or terretonin ring systems under abiotic reaction conditions. The first total syntheses of members of these natural product families are reported as their racemates.
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