Esterification of 9-fluorenylmethoxycarbonyl-glycosylated serine and cysteine derivatives with an hydroxymethyl resin.
Esterification of glycosylated serine and cysteine derivatives with a 4-alkoxybenzyl alcohol (Wang) resin is described. The classical methods of ester bond formation (symmetrical anhydride, 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate [TBTU]/4-dimethylaminopyridine [DMAP] with or without 1-hydroxybenzotriazole [HOBT], pentafluorophenyl [Pfp] esters gave high percentages of racemization of the glycosylated serine or cysteine residues. To reduce the D-amino acid content, we found that the best results were obtained with the highly efficient MSNT reagent (2,4,6-mesitylenesulfonyl-3-nitro-1,2,4-triazolide), which gave a high yield of substitution of the resin and the lowest percentage of racemization. A difference in behavior was observed between the two amino acids. The glycosylated cysteine derivative always gave lower racemization than the analogous glycosylated serine.
Harth-Fritschy
E
E
Institut Pasteur, Département de Biochimie et Génétique Moléculaire, Paris, France.
Cantacuzène
D
D
D000409:Alanine / Q000031:analogs & derivatives; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D003545:Cysteine / Q000031:analogs & derivatives* / Q000737:chemistry*; D004136:Dinitrobenzenes; D004951:Esterification; D005449:Fluorenes / Q000737:chemistry; D006031:Glycosylation; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D010455:Peptides / Q000737:chemistry; D012116:Resins, Plant; D012694:Serine / Q000031:analogs & derivatives* / Q000737:chemistry*; D013237:Stereoisomerism; D014227:Triazines / Q000737:chemistry*
C110274:2,4,6-mesitylenesulfonyl-3-nitro-1,2,4-triazolide; D000596:Amino Acids; D004136:Dinitrobenzenes; D005449:Fluorenes; D007202:Indicators and Reagents; C016456:N(alpha)-fluorenylmethyloxycarbonylamino acids; D010455:Peptides; D012116:Resins, Plant; D014227:Triazines; D012694:Serine; C047134:Marfey's reagent; D003545:Cysteine; D000409:Alanine