Synthesis of Azetidinones from L-Threonine: Formation of Unusually Stable Bicyclic Hemiketals andcis-Azetidinones
- 1 January 1990
- journal article
- letter
- Published by Georg Thieme Verlag KG in Synlett
- Vol. 1990 (07) , 431-432
- https://doi.org/10.1055/s-1990-21119
Abstract
L-Threonine-based synthesis of azetidinones/penems leads to the desired trans-azetidinones as well as novel, unusually stable bicyclic hemiketals/cis-azetidinones. The latter compounds are resistant to Baeyer-Villiger oxidation, and hence they can not be used towards penem synthesis. Structures of the bicyclic hemiketal, (1S,2R, 4R,5R)-4-(4-chlorophenyl)-4-hydroxy-6-(4-methoxyphenyl)-2-methyl-3-oxa-6-azabicyclo[3.2.0]heptan-7-one, and the cis-azetidione, (3S, 4R)-3-[(R)-1-(acetoxy)ethyl]-4-(4-chlorobenzoyl)-1-(4-methoxyphenyl)-2-azetidinone, were established by x-ray crystallography.Keywords
This publication has 0 references indexed in Scilit: