| Title: | Absolute Configurations of Stink Bug- and Plant-Produced Sesquipiperitols via Synthesis of All Stereoisomers |
| Author(s): | Khrimian A; Guggilapu SD; Guzman F; Blassioli-Moraes MC; Borges M; |
| Address: | "Invasive Insect Biocontrol and Behavior Laboratory, USDA-ARS, Beltsville Agricultural Research Center, Room 301, Building 007, 10300 Baltimore Avenue, Beltsville, Maryland 20705, United States. National Institute of Diabetes and Digestive and Kidney Diseases, Laboratory of Bioorganic Chemistry, National Institutes of Health, Bethesda, Maryland 20892, United States. Semiochemicals, Embrapa Genetic Resources and Biotechnology, 70770-917 Brasilia-DF, Brazil" |
| DOI: | 10.1021/acs.jnatprod.0c00517 |
| ISSN/ISBN: | 1520-6025 (Electronic) 0163-3864 (Linking) |
| Abstract: | "Sesquipiperitol is a sesquiterpene alcohol, some stereoisomers of which were found in several plant species. The biological role of these compounds in plants and their absolute configurations have not been reported. Recently, we found that 1S,6S,7R stereoisomer of sesquipiperitol was a key precursor in the biosynthesis of the harlequin bug, Murgantia histrionica, pheromone, which consists of two stereoisomeric zingiberenol oxides. In addition, the Tibraca limbativentris stink bug was shown to produce two sesquipiperitol stereoisomers as minor components in their male-produced sex pheromone, the main constituents of which were zingiberenols. To determine absolute configurations of plant- and stink-bug-produced sesquipiperitols, we undertook syntheses of all stereoisomers of this sesquiterpene alcohol. The syntheses were based on 1,10-bisaboladien-3-ols (aka zingiberenols) with known configurations at C-6 and C-7, the oxidation of which provided sesquipiperitone precursors with retention of configurations of these stereogenic centers. The foremost challenge of the synthetic endeavor was the assignment of absolute configurations of secondary carbinol centers, which was resolved by NMR analyses of corresponding Mosher's esters. Thus, the availability of all eight diastereomers allowed us to assign sesquipiperitols from Fitzroya cupressoides and Argyranthemum adauctum spp. jacobaeifolium plants 1S,6S,7R (16) and 1R,6R,7S (14) configurations, respectively. A chiral-phase gas-chromatographic method was developed to determine 1S,6S,7R and 1R,6S,7R (15) configurations of T. limbativentris sesquipiperitol pheromone components" |
| Keywords: | Animals Heteroptera/*chemistry Molecular Structure Oxidation-Reduction Plants/*chemistry Sesquiterpenes/*chemistry/isolation & purification Stereoisomerism; |
| Notes: | "MedlineKhrimian, Ashot Guggilapu, Sravanthi D Guzman, Filadelfo Blassioli-Moraes, Maria Carolina Borges, Miguel eng 2020/07/11 J Nat Prod. 2020 Jul 24; 83(7):2281-2286. doi: 10.1021/acs.jnatprod.0c00517. Epub 2020 Jul 10" |
