First total synthesis of aspinolide B, a new pentaketide produced by Aspergillus ochraceus.
The first asymmetric total synthesis of Aspinolide B (1), a new 10-membered lactone discovered by chemical screening methods in the cultures of Aspergillus ochraceus, has been accomplished. The key steps included a selective Felkin-type addition of TMS-acetylene to aldehyde 3a and a Nozaki-Hiyama-Kishi coupling reaction to build the required 10-membered ring. This synthesis confirmed the absolute stereochemistry of aspinolide B, established through Helmchen's method and corrected its previously reported specific optical rotation.
Pilli
R A
RA
Instituto de Química, Unicamp, Cx. Postal 6154, 13083-970 Campinas, SP Brazil. pilli@iqm.unicamp.br
Victor
M M
MM
de Meijere
A
A
D001235:Aspergillus ochraceus / Q000737:chemistry*; D002849:Chromatography, Gas; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry; D009904:Optical Rotation; D013237:Stereoisomerism
D007783:Lactones; C415190:aspinolide B