96520-22-8Relevant articles and documents
The total synthesis of ganglioside GM3
Duclos Jr., Richard I.
, p. 489 - 507 (2007/10/03)
Previous syntheses of ganglioside GM3 (NeuAcα3Galβ4Glcβ1Cer) are reviewed, and both chemoenzymatic and chemical total synthetic approaches were investigated. In a chemoenzymatic approach, (2S,3R,4E)-5'''-acetyl-α-neuraminyl-(2''' → 3'')-β-galactopyranosyl-(1'' → 4')-β-glucopyranosyl-(1' mutually implies 1)-2-azido-4-octadecene-1,3-diol (azidoGM3) was readily prepared utilizing recombinant β-Gal-(1'' → 3'/4')-GlcNAc α-(2''' → 3'')-sialyltransferase enzyme, and was evaluated as a synthetic intermediate to ganglioside GM3. The chemical total synthesis of ganglioside GM3 was performed on one of the largest scales yet reported. The highlights of this synthesis include minimizing the steps necessary to prepare the lactosyl acceptor as a useful anomeric mixture, which was present in excess for the highly regioselective and fairly stereoselective sialylation with a known neuraminyl donor to give the protected GM3 trisaccharide. The synthetic methodology maximized convergence by a subsequent glycosidic coupling of the well-characterized GM3 trisaccharide trichloroacetimidate derivative with protected ceramide. The ganglioside GM3 was nearly homogeneous as the two glycosidic couplings utilized preparative HLPC purifications, and variations in the sphingosine base and fatty acyl group were under 0.1 and 0.2%, respectively. (C) 2000 Elsevier Science Ltd.
Efficient sialylation with phosphite as leaving group
Martin, Thomas J.,Schmidtrk, Richard R.
, p. 6123 - 6126 (2007/10/02)
The search for an acid labile leaving group attached to the anomeric position of O-protected N-acetylneuraminic acid led to phosphite derivative 1c which provided in the presence of catalytic amounts of trimethylsilyl trifluoromethanesulfonate the desired
SYNTHESIS OF α-Neu5Acp-(2--3)-D-Gal AND α-Neu5Acp-(2--3)-β-D-Galp-(1--4)-D-Glc
Ogawa, Tomoya,Sugimoto, Mamoru
, p. C5 - C9 (2007/10/02)
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