Lutz Muller

Untersuchungen zur struktur des α-d-glucosidaseinhibitors acarbose

Abstract Hydrolysis of the pseudotetrasaccharide acarbose ( 1 ), a potent inhibitor of intestinal α- d -glucosidases and an effective oral antidiabetic agent, gave d -glucose and a tricyclic compound (1 R ,2 S ,3 R ,4a S ,7 R ,8 S ,8a S ,9a R )-1,2,3,4a,7,8,8a,9a-octahydro-1,2,7,8-tetrahydroxy-3- [(1 R )-1-hydroxyethyl]-6-hydroxymethylpyrrolo-[2,1- b ]benzoxazole ( 6 ) that was further degraded into 1 l -(1,2,4/3)-1-hydroxymethyl-2,3,4-cyclohexanetriol (validatol, 25 ) and (2 R ,3 S ,4 S )-2-[(1 R )-1-hydroxyethyl]-pyrrolidine-3,4-diol ( 49 ) by sodium borohydride reduction and subsequent catalytic hydrogenation. Methanolysis of 1 afforded α- and β-glycosides 11 and 10 which were cleaved by hydrogenation to give 25 and methyl α- and β-glycosides of 4-amino-4,6-dideoxy-α- and β- d -glucopyranose (viosamine, 38 ). Upon hydrogenation, 1 gave, beside several minor products, 25 and a basic trisaccharide that was acetolyzed into the peracetates of viosamine 38 and d -glucose. The structure of 6 was determined by derivatives and ring-cleavage products. N.m.r. and mass spectra of the acarbose products and derivatives are discussed.

Analytische Charakterisierung von Palatinit

SummaryThe reaction product of the catalytic hydrogenation of isomaltulose (palatinose) is a mixture ofα-d-glucopyranosido-1,6-sorbitol and α-d-glucopyranosido-1,6-mannitol designated palatinit. Because of its high potential as a sugar substitute methods for the identification and characterization of hydrogenation products and for the determination of palatinit as an ingredient in food preparations and biological samples are required. Several working procedures are described in full detail including thin layer and gas chromatography as well as enzymatic and chemical determinations.ZusammenfassungDas Reaktionsprodukt der katalytischen Hydrierung von Isomaltulose (Palatinose) ist eine Mischung vonα-d-Glucopyranosido-1,6-sorbit undα-d-Glucopyranosido-1,6-mannit und wird als Palatinit bezeichnet. Seine Eignung als potentieller Zuckeraustauschstoff macht Methoden zur Identifizierung und Charakterisierung der Hydrierungsprodukte und zur Bestimmung von Palatinit als Bestandteil von Lebensmitteln und biologischem Material erforderlich. Mehrere Arbeitsvorschriften werden detailliert wiedergegeben; sie umfassen Dünnschicht- und Gaschromatographie ebenso wie enzymatische und chemische Bestimmungsmethoden.

Drug concentration monitoring, microbial alpha-glucosidase inhibitors, plasminogen activators

Drug Concentration Monitoring.- Microbial Alpha-Glucosidase Inhibitors: Chemistry, Biochemistry and Therapeutic Potential.- Plasminogen Activators: Molecular Properties, Biological Cell Function and Clinical Application.- Author Index Volumes 1-7.