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| Author(s): |
Carla Cristina Perez
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Química |
| Defense date: | 2012-06-29 |
| Examining board members: |
Luiz Carlos Dias;
Adriano Lisboa Monteiro;
Simon John Garden;
Antonio Claudio Herrera Braga;
Carlos Roque Duarte Correia
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| Advisor: | Luiz Carlos Dias |
| Abstract | |
The saliniketals A (1) and B (2) were isolated in 2007 by Fenical and coworkers from Salinispora arenicola and showed to be important inhibitors of ornithine decarboxylase. We concluded the synthesis of C-4/C-17 fragment (19) after 19 steps in 5.5% overall yield from Roche ester (longest linear sequence). This work was always focused on the search for the more creative and efficient synthetic route. The key steps involved an efficient syn-aldol reaction for the preparation of adducts 139 and a double diastereo-differentiating aldol reaction for the preparation of 134b. Substrate controlled Grignard reaction provide 169, and an intramolecular Wacker-type cyclization established the bicyclic spiroketal in 29. The Seyferth-Gilbert homologation was used in the preparation of alkyne 187 and a syn-hydrostannation provided the vinyl stannane 19. This result allowed the unequivocal determination of the stereochemistry for all stereocenters formed by comparison with data obtained from the literature. We are able to conclude a formal total synthesis of saliniketals A and B and the synthetic route is, in principle, amenable to a large scale synthesis (AU) | |
| FAPESP's process: | 07/08564-0 - Total synthesis of the bicyclic polyketide salineketal A |
| Grantee: | Carla Cristina Perez |
| Support Opportunities: | Scholarships in Brazil - Doctorate |