1 research outputs found
Regioselective One-Pot Benzoylation of Triol and Tetraol Arrays in Carbohydrates
Protection of 2,3,4-<i>O</i>-unprotected α-galacto-
and α-fucopyranosides with BzCN and DMAP/DIPEA as the base afforded
directly and regioselectively the 3-<i>O</i>-unprotected
derivatives. The rationale for these studies was to take advantage
of the eventual cooperativity of the “cyanide effect”
and “the alkoxy group mediated diol effect”. This way,
even the totally unprotected α-galactopyranosides could be regioselectively
transformed into the corresponding 2,4,6-<i>O</i>-protected
derivatives. The great utility of these building blocks was demonstrated
in efficient trisaccharide syntheses