1- Thio-P-D-galactopyranoside

M. Yde and C. K. De Bruyne, Binding of substituted phenyl 1-thio-P-D-galactopyranosides to P-D-galactosidase from E. coli, Carbohydr. Res., 60 (1978) 155-165. 

A solution of ethyl 1-thio- p-D-galactopyranoside (5 g, 12.9 mmol) and dibutyhin oxide (3.2 g, 13 mmol) in MeOH (500mL) was boiled under reflux for 4 h. Removal of the solvent gave a white powder that was dissolved in dry THF (500mL). r-Butyldimethylsilylchk>ride (1.95 g, 13 mmol) was added to the solution and left to stir for 24 h at room temperature, after which time TLC (9 1, CHjClj/MeOH) showed that no starting material remained. 

Chloroethyl 1-thio-P-D-galactopyranoside and the corresponding glucoside are suitable glycosylating agents for the preparation of glycoconjugates. ... 

Isopropyl 3,4-O-isopropylidene-0E-L-f 7iAro-pentopyranosid-2-ulose, P-42 Isopropyl (methyl 2,3-0-isopropylidene-p-D-ribofuranosid)uronate, R-146 Isopropyl 2,3,4,5,6-penta-O-acetyl-D-galactonate, G-23 Isopropyl 1-thio-p-D-galactopyranoside, T-65 Isopropyl 1-thio-a-D-glucopyranoside, T-65... 

Isopropyl 1-thio-p-D-galactopyranoside, T-65 Isopropyl 1-thio-a-D-glucopyranoside, T-65... 

In the next steps, the relative reactivities of armed and disarmed (active) p-Ai-acetamidophenyl 1-thioglycosides were established using perbenzoylated p-nitrophenyl 1-thioglycoside 17 as the acceptor (disarmed-latent) (Scheme 7). To this end, fully benzoylated and benzylated p-Ai-acetamidophenyl 1-thio-p-D-galactopyranosides 29 and 47 were glycosylated with 17 using TfOH in a 1.5 1 M ratio relative to the acceptor. Similar to the results obtained from 37 and 43,... 

Aminophenyl di-A-acetyl-p-chitobioside 4-Aminophenyl 1-thio- p-D-galactopyranoside... 

Benzaldehyde dimethyl acetal (0.63 mL, 4.17 mmol) and 10-camphorsulfonic acid (27 mg, 0.12 mmol) were added to a vigorously stirred suspension of ethyl 1-thio-P-D-galactopyranoside (5," 500 mg, 2.32 mmol) in CH3CN (10 mL), and the mixture was refluxed for 15-20 min. After work-up, as described above, CTystaUization gave 6 as white crystals (542 mg, 75%). m.p. 157.5-158.5 C (CH2CI2 - hexanes),... 

Synthesis of Phenyl 2,3,4,6-Tetra-0-acetyl-1-thio-P-D-galactopyranoside 273... 

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