STEREOSELECTIVE SYNTHESIS OF METHYL TETRA-0-METHYL a-AND P-D-GLUCO-AND MANNOPYRANOSIDES
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Abstract:
Methyl tetra - 0-methyl- ?-D- glucopyranoside is stereoselectively prepared from tetramethyl-D- glucopyranose by using (MeI+NaH) in toluene (86%) or cyclohexane (85%), while its ?- isomer is best synthesized in hexamethyl phosphoramide (64%). Similarly, methyl tetra-o-methyl-?- D-mannopyranoside is synthesized in cyclohexane (80%), while its ?- isomer is predominantly prepared by (MeI+n-BuLi) in cyclohexane (98%). The ?-and ?- isomers of these glycosides were identified and quantified by G.C
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Journal title
volume 3 issue 1
pages -
publication date 1992-06-01
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