Collect. Czech. Chem. Commun.
1996, 61, 1489-1500
https://doi.org/10.1135/cccc19961489
Preparation and Reactions of 2-Chloroethyl 1-Thio-β-D-glycopyranosides Derived from D-Galactose, D-Glucose, and 2-Acetamido-2-deoxy-D-glucose
Miloslav Černýa, Tomáš Trnkaa and Miloš Buděšínskýb
a Department of Organic Chemistry, Charles University, 128 40 Prague 2, Czech Republic
b Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 166 10 Prague 6, Czech Republic
Abstract
Chloroethyl 1-thio-β-D-glycopyranosides of the D-galacto and D-gluco configurations 5a-5c were prepared by alkylation of the corresponding 1-thio-β-D-hexopyranoses 3a-3c with 1-bromo-2-chloroethane followed by deacetylation. The starting 1-thio-β-D-hexopyranoses were obtained from the acetylated glycopyranosyl halides via isothiouronium salts. It was demonstrated that the chloroethyl thioglycosides 5a-5c undergo hydrolysis in aqueous solutions to give the 2-hydroxyethyl thioglycosides 6a-6c and reducing hexoses and that this hydrolysis proceeds via episulfonium salts. The hydrolysis was monitored by 1H and 13C NMR spectroscopy. In 1% aqueous solutions of sodium carbonate containing phenol or aniline, the thioglycosides 5a-5c provide, in addition to the above hydrolysis products, also the phenoxyethyl and phenylaminoethyl thioglycosides 9a, 10a and 9b, 10b, respectively.
Keywords: 2-Halogenoethyl thioglycosides; Synthesis; Nucleophilic substitution; Mechanism of hydrolysis; 1H and 13C NMR.
