J. Bigorra et al., SYNTHETIC APPROACHES TO EITHER HOMOCHIRAL OR ACHIRAL DERIVATIVES OF 3-HYDROXY-2(5H)-FURANONE (ISOTETRONIC ACID), Tetrahedron, 49(30), 1993, pp. 6717-6728
Several title compounds were synthesized according to new methods base
d either on the use of D-ribonolactone as a chiral precursor or on the
cyclization of 2,4-dioxopentanoic acid as a suitable achiral precurso
r. Base-induced elimination and subsequent acid-promoted ring contract
ion is an efficient protocol for the preparation of isotetronic acids
from 2-O-alkyl-3,4-O-benzylidene-D-ribono-1,5-lactone derivatives.