An efficient two-step route to pyridoxatin analogues 13 and 15 has been developed. Condensation of 4-hydroxypyridone (4) with citronellal (10) affords o-quinone methide intermediate 11, which reacts further to give inverse electron demand Diels-Alder adducts 12 and 16 and ene adduct 14. Oxidation of 12 and 14 with MoO5 by Sammes' procedure completes the synthesis of 13 and 15. Using this approach, the first total synthesis of(+/-)-pyridoxatin (1) has been carried out in seven steps from cis-2,4-dimethylcyclohexanone (21). The key step is the condensation of 4-hydroxypyridone (4) with the allylic silane aldehyde 26 to give 35% of cyclohexylpyridones 2 and 30.
Chaunopyran A: Co-Cultivation of Marine Mollusk-Derived Fungi Activates a Rare Class of 2-Alkenyl-Tetrahydropyran
作者:Zhuo Shang、Angela A. Salim、Robert J. Capon
DOI:10.1021/acs.jnatprod.7b00144
日期:2017.4.28
Co-cultivation of Chaunopycnis sp. (CMB-MF028) and Trichoderma hamatum (CMB-MF030), fungal strains co-isolated from the inner tissue of an intertidal rock platform mollusc (Siphonaria sp), resulted in transcriptional activation of a rare class of 2-alkenyl-tetrahydropyran, chaunopyran A (7), and biotransformation and deactivation of the antifungal pyridoxatin (1), to methyl-pyridoxatin (8). This study illustrates the complexity of offensive and counter-offensive molecular defenses encountered during fungal co-cultivation, and the opportunities for activating new, otherwise transcriptionally silent secondary metabolites.
SHIKIMATE ANALOGUES AND METHODS OF USE
申请人:The Board of Regents of the University of Oklahoma
公开号:US20190038579A1
公开(公告)日:2019-02-07
The present disclosure, in at least certain embodiments, is directed to shikimate (shikimic acid) analogues and compositions thereof, kits which contain the shikimate analogues or compositions thereof, and methods of use of the compounds and compositions for treating epithelial surfaces before or following exposure to irritants, allergens, and toxic agents (for example, urushiol).
[EN] SHIKIMATE ANALOGUES AND METHODS OF USE<br/>[FR] ANALOGUES DE SHIKIMATE ET MÉTHODES D'UTILISATION
申请人:UNIV OKLAHOMA
公开号:WO2017142866A1
公开(公告)日:2017-08-24
The present disclosure, in at least certain embodiments, is directed to shikimate (shikimic acid) analogues and compositions thereof, kits which contain the shikimate analogues or compositions thereof, and methods of use of the compounds and compositions for treating epithelial surfaces before or following exposure to irritants, allergens, and toxic agents (for example, urushiol).