Collection of Czechoslovak Chemical Communications - digital archive 

Abstract

3-Trifluoroacetamido-4-O-trifluoroacetyl-2,3,6-trideoxy-α,β-L-lyxopyranosyl chloride (VII) was coupled under Koenigs-Knorr glycosidation conditions to (7S)-O-(2-hydroxyethyl)daunomycinone (IV), (7R)-O-(2-hydroxyethyl)daunomycinone (V), and (7S)-O-(4-hydroxy-2-butynyl)daunomycinone (VI). The deprotection of isolated N-trifluoroacetyl derivatives of α- and β-glycosides XVI, XVII, XX, XXI, and XXIV yielded free glycosides XVIII, XIX, XXII, XXIII, and XXV. Their anomeric configuration was determined by NMR spectroscopy. Reaction of 3,4-di-O-acetyl-2,6-dideoxy-α,β-L-arabinopyranosyl chloride (II) with IV gave glycosides XII and XIII. Their deacetylation provided free glycosides XIV and XV. An analogueous reaction with 3-acetamido-4-O-acetyl-2,3,6-trideoxy-α,β-L-lyxopyranosyl chloride (III) with IV lead to the N-acetyl glycoside IX only.