title: Preparation of deacetyl-, lyso-, and deacetyl-lyso-GM(3) by selective alkaline hydrolysis of GM3 ganglioside.
abstract: Three methods (using GM3 quantities ranging from a few milligrams to grams) have been developed to prepare, in high yield, the three derivatives of ganglioside GM3 [alpha-Neu5Ac-(2-3)-beta-Gal-(1-4)-beta-Glc-(1-1)-ceramide]: deacetyl-GM3 [alpha-Neu-(2-3)-beta-Gal-(1-4)-beta-Glc-(1-1)-ceramide], lyso-GM3 [alpha-Neu5Ac-(2-3)-beta-Gal-(1-4)-beta-Glc-(1-1)-sphingosine], and deacetyl-lyso-GM3 [alpha-Neu-(2-3)-beta-Gal-(1-4)-beta-Glc-(1-1)-sphingosine]. This is the first report of the preparation of lyso-GM3 by a one-pot reaction. We can now define the optimal conditions for the different preparations. Preparation of deacetyl-GM3: alkaline reagent, 2 M KOH in water; GM3 concentration, 33 mg/ml; reaction temperature, 90 degrees C; reaction time, 3.5 h; nitrogen atmosphere. Preparation of deacetyl-lyso-GM3: alkaline reagent, 8 M KOH in water; GM3 concentration, 10 mg/ml; reaction temperature, 90 degrees C; reaction time, 18 h; nitrogen atmosphere. Preparation of lyso-GM(3): alkaline reagent, 1 M sodium tert-butoxide in methanol; GM3 concentration, 10 mg/ml; reaction temperature, 80 degrees C; reaction time, 18 h; anhydrous conditions. The percentage yield of deacetyl-GM3 was 70;-75%, that of deacetyl-lyso-GM3 100%, and of lyso-GM3 36;-40%.Deacetyl-GM3, deacetyl-lyso-GM3, and lyso-GM3 were purified by column chromatography, and chemical structures were confirmed by electron spray-mass spectrometry.
authors.affiliation: Vaccines Department, Center of Molecular Immunology, Havana 11600, Cuba.
authors.forename: O
authors.initials: O
authors.lastname: Valiente
authors.forename: L
authors.initials: L
authors.lastname: Mauri
authors.forename: R
authors.initials: R
authors.lastname: Casellato
authors.forename: L E
authors.initials: LE
authors.lastname: Fernandez
authors.forename: S
authors.initials: S
authors.lastname: Sonnino
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003124:Colorimetry; D005679:G(M3) Ganglioside / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000302:isolation & purification; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D006878:Hydroxides; D007700:Kinetics; D019158:N-Acetylneuraminic Acid / Q000737:chemistry; D009438:Neuraminic Acids / Q000737:chemistry; D017680:Potassium Compounds; D021241:Spectrometry, Mass, Electrospray Ionization; D013110:Sphingosine / Q000737:chemistry; D014316:Tritium
chemical_list: D005679:G(M3) Ganglioside; D006878:Hydroxides; D009438:Neuraminic Acids; D017680:Potassium Compounds; C056605:lyso-G(M3) ganglioside; D014316:Tritium; D019158:N-Acetylneuraminic Acid; D013110:Sphingosine; C029943:potassium hydroxide