ISSN:
0170-2041
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Reactions of Enolic Sugar Derivatives, XVI. - Synthesis of a Diastereotopic Proton Probe [(Z-3,7-Anhydro-1,2-dideoxy-D-gluco-oct-2-enitol] for α- and β-D-GlucosylasesFor the elucidation of the stereochemistry in glucosylase-catalyzed proton addition reactions Z)-3,7-anhydro-1,2-dideoxy-D-gluco-oct-2-enitol (1) was synthesized. Starting material for the multistep synthesis is 3,4,5,7-tetra-O-acetyl-2,6-anhydro-1-C-(1,3-diphenyl-2-imidazolidinyl)-D-glycero-D-gulo-heptose (4), which after chain elongation by Grignard reaction yields the separable diastereomeric alcohols 3,7-anhydro-4,5,6,8-tetra-O-benzyl-1-desoxy-D-erythro-L-galacto-octitol (14) and -L-talo-octitol (15). After O tosylation of the hydroxy group in position 2 and replacement of the O benzyl by O acetyl groups in compounds 14 and 15, the resulting isomeric products were subjected to reaction with sodium benzoate. One isomer, 3,7-anhydro-1-deoxy-4,5,6,8-tetra-O-acetyl-2-O-(p-tolylsulfonyl)-D-erythro-L-galacto-octitol (16), yields the title compound 1 in reasonable quantity in addition to the nucleophilic substitution product 19. Several glucosylases catalyze the addition of water to the double bond of 1.
Notes:
Für die Untersuchung der Stereochemie enzymatischer Protonierungsschritte bei Glucosylasen wurde Z)-3,7-Anhydro-1,2-didesoxy-D-gluco-oct-2-enitol (1) synthetisiert. Edukt für die mehrstufige Synthese ist die 3,4,5,7-Tetra-O-acetyl-2,6-anhydro-1-C-(1,3-diphenyl-2-imidazolidinyl)-D-glycero-D-gulo-heptose (4), die nach Kettenverlängerung durch Grignard-Reaktion die diastereomeren Alkohole 3,7-Anhydro-4,5,6,8-tetra-O-benzyl-1-desoxy-D-erythro-L-galacto-octitol (14) und -L-talo-octitol (15) liefert. Letztere werden nach O-Tosylierung der 2-Hydroxygruppe und Austausch der O-Benzylschutzgruppen gegen O-Acetylgruppen der Reaktion mit Natriumbenzoat unterworfen. 3,7-Anhydro-1-desoxy-4,5,6,8-tetra-O-acetyl-2-O-(p-tolylsulfonyl)-D-erythro-L-galacto-octitol (16) liefert neben dem Substitutionsprodukt 19 in nennenswerter Ausbeute 1. Zahlreiche Glucosylasen katalysieren die Umsetzung von 1 zu Additionsprodukten.
Additional Material:
1 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.198419840604
