Synthesis of An Enantio-Enriched Iridolactone Core in Brasoside.
Authors
Makama B. Y.
Department of Petroleum Chemistry,American University of Nigeria, Lamido Zubairu Way,P.M.B. 2250, Yola, Adamawa State
Abstract
A three step enantio-enriched protocol to the iridolactone core of brasoside is reported. Stereo-control reduction of [(1S,2R,3S)-3-methyl-2(nitromethyl)-5-oxocyclopentyl]acetic acid 3 afforded (3aR,4S,5R,6aS)-5-methyl-4-(nitromethyl)-hexahydrocyclopenta[b]furan-2-one 4. A further formylation strategy on the AB-ring system 4 afforded the enol ester 5, followed by Nef reaction of the nitoo functionality and acid quenching to the desired tricyclic lactone 11. Chiral ɤ-keto-acid 3 was used, since this precursor contains three functional groups: ketone, carboxylic acid, nitromethyl; it is also available in bulk as a pure enantiomer at low price
Author Biography
Makama B. Y., Department of Petroleum Chemistry,American University of Nigeria, Lamido Zubairu Way,P.M.B. 2250, Yola, Adamawa State
Head and Senior Lecturer, Department of Biological Sciences