stereoselective synthesis of methyl tetra-0-methyl a-and p-d-gluco-and mannopyranosides
نویسندگان
چکیده
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
منابع مشابه
STEREOSELECTIVE SYNTHESIS OF METHYL TETRA-0-METHYL a-AND P-D-GLUCO-AND MANNOPYRANOSIDES
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-Bu...
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عنوان ژورنال:
journal of sciences islamic republic of iranجلد ۳، شماره ۱، صفحات ۰-۰
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