| Research Abstract |
A new fluorescent protecting group, 3-N-(5-dimethylaminonaphthalene-1-sulfonyl) aminopropionyl (DSAP) group, was introduced to mannose derivatives for non-destructive monitoring in the solid-phase synthesis of oligosaccharides. The mannosyl trichloro-actimidate with the DSAP group was glycosylated to Wang type resins, and then the DSAP group was readily removed by NaOMe. The corresponding methyl ester (DSAP-OMe) is potential to quantify the yield of the solid phase reactions. This fluorometric monitoring method using O-DSAP group is possible to sensitively detect all the situations such as not only expected reactions but also unexpected degradation similar to TLC analysis of solution synthesis. Thus, this fluorometric monitoring using O-DSAP protecting group is the most reliable method for solid-phaseoligosaccharide syntheses.
Next a new acyl-type protecting group (N-C_8F_<17>C_2H_4CO-N-_8F_<17>C_3H_6-aminopropionyl group ; PFP group) was synthesized. Fluorous oligosaccharide synthesis was tried from methyl 2, 3, 4-tri-O-PFP-D-mannopyranoside using 2, 3, 4-tri-O-acetyl-6-O-t-butyldiphenylsilyl-D-glucopyranosyl trichloroacetimidate. After glycosidation the desired disaccharide was obtained easily from perfuluorocarbon (Fluorinart^<TM>) phase by only extraction with organic solvent. By this synthetic strategy we obtained the corresponding tetrasaccharide in good yield. Thus, this fluorous synthesis using PFP group is possible to take the place of the solid-phase oligosaccharide synthesis.
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