Rocchi R, Biondi L, Filira F, Gobbo M, Dagan S, Fridkin M
Int J Pept Protein Res. 1987 Feb;29(2):250-61. doi: 10.1111/j.1399-3011.1987.tb02252.x.
Synthesis of some modified tuftsins is described in which a monosaccharide or a monosaccharide derivative was incorporated in the molecule. Acylation of H-Thr-Lys(Z)-Pro-Arg(NO2)-OBzl with D(+)-gluco-1,5-lactone followed by catalytic hydrogenation gave N alpha-gluconyl-tuftsin. Glycosylation of the carboxyl function of the C-terminal arginine has been achieved by reacting, through the mixed anhydride procedure, Boc-Thr-Lys(Z)-Pro-OH with 2-deoxy-2-(NG-nitroargininamido)-D-glucopyranose followed by catalytic hydrogenation and trifluoroacetic acid treatment. O-Glucosyl-tuftsin has been prepared by reacting o-nitrophenyl N-benzyloxycarbonyl-O-[(alpha + beta) 2,3,4,6-tetra-O-benzyl-D-glucopyranosyl]-threoninate with H-Lys(Z)-Pro-Arg(NO2)-OBzl in the presence of 1-hydroxybenzotriazole. Flash chromatography on silica gel allowed a partial separation of the diastereoisomers, one of which has been isolated in a reasonable yield. The single diastereoisomer and the alpha + beta anomeric mixture were separately deblocked by catalytic hydrogenation and purified by RP-HPLC.
