Within the past few decades, interest in the field of aminosugar chemistry has been stimulated to a remarkable degree and the discovery and syntheses of a wide range of new aminosugars of differing types, for example of two monoamino-tetroses (12,19), nineteen monoamino-pentoses, two diamino-pentoses, thirty-three monoamino-hexoses, and eighteen diamino-hexoses (20) have been accomplished. It is well undterstood that the aminosugars, significant constituents in mnay biologically important materials (11), consist of substances that may be regarded a teh condesation products of an amine and a carbohydrate. Falling into this category are the 2-amino-hexoses which may be derived conceptually as the condensation of ammonia with carbon atom number 2 or a hexose. (4). Thus, D-glucose is the conceptual parent of D-glucosamine (i.e., 2-amino-2-deoxy-D-Glucose). D-allosamine is one of the rarer aminosugars about which very little is know concerning chemical properties and derivatives. A few studies have recently been made on the beta series of benzyl D-allosaminides after it was shown by Gross et al. (5) that the use of benzyl N-benzoyl-4, 6-0-benzylidene-β-D-glucosaminide as an intermediate in the synthesis of D-allosamine derivative proved fruitful for large-scale preparation of the β-D-allosaminide derivatives. This basic work has established conditions which have made it possible and desireable to conduct also an investigatin into the chemistry of the alpha series of D-allosaminides. Thus it appeared that a procedure involving the benzyl N-benzoyl-α-D-glucosaminide might well afford the alpha anomeric D-allosaminides. Although several benzyl N-benzoyl-hexosaminides are known (1,5,20), no information is yet available in the literature about benzyl N-benzoyl-α-D-glucosaminide from the standpoint of chemical properties and derivatives. To explore processes from making derivatives of D-allosamine particularly in the series of alpha-anomers, it is necessary to investigate the chemistry of benzyl N-benzoyl-α-D-glucosaminide and its derivatives, preparatory to an attempt to enter the alphaseries of D-allosaminides. Therefore, the principal interest of this investigation was to prepare and to investigate properties of benzyl N-benzoyl-α-D-glucosaminide and its derivatives, and to explore its utility as a possible precursor for the preparation of benzyl 3-0-benzoyl-α-D-allosaminide hydrochloride by the method analogous to the synthesis of the corresponding beta-anomer.

No description available.

No description available.

This thesis describes the synthesis of three novel seven carbon bicyclic mimics of α-L-fucose, and of two new pyrrolidine amino sugars. 2,7-Anhydro- l-deoxy-β-L-gulo-heptulopyranose and l,2,7-trideoxy-2,7-imino-β- L-gulo-heptulopyranose were both synthesised from L-gulono-l,4-lactone. The addition of one equivalent of methyllithium to the diacetonide of L-gulono-1,4- lactone gave a keto-sugar, l-deoxy-3,4;6,7-di-0-isopropylidene-β-L-gulo- heptulofuranose. The anomeric configuration of this compound was determined by equilibrium nOe measurements. Hydrolysis in aqueous trifluoroacetic acid caused simultaneous deprotection, isomerisation and dehydration to yield 2,7-anhydro-l-deoxy-β-L-guloheptulopyranose, a highly stable, rigid bicyclic system. The structure of the bicyclic system was confirmed by X-ray crystallographic studies on a crystalline derivative. The introduction of nitrogen at C-6 of L-gulono-l,4-lactone was achieved via the azide displacement of the known bromide, 6-bromo-6-deoxy-2,3-0- isopropylidene-L-gulono-l,4-lactone. Protection of the C-5 hydroxyl group as its silyl ether was followed by the addition of one equivalent of methyllithium to the carbonyl group to give a keto-sugar, 7-azido-6-(0-tert-butyldimethylsilyl-l,7- dideoxy-3,4-0-isopropylidene-β-L-gulo-heptulofuranose. Removal of the protecting groups followed by reduction of the azide functionality gave the bicyclic hemiaminal, l,2,7-trideoxy-2,7-imino-β-L-gulo-heptulopyranose, a stable but hygroscopic solid. A third bicyclic system, 2,7-anhydro-l,2,6-trideoxy-2,6-imino-β-L-gulo- heptulopyranose, was synthesised from diacetone-D-mannose via the known ketosugar, 6-azido-7-0-tert-butyldimethylsilyl-l,6-dideoxy-3,4-0-isopropylidene-β- L-gulo-heptulofuranose. Removal of the protecting groups from this keto-sugar, followed by reduction of the azide functionality, gave the target system. Analysis of the NMR spectra showed that this existed as an equilibrium mixture of the closed, bicyclic hemiaminal form and the monocyclic imine form, with the bicyclic form predominating in all solvents investigated. The sodium borohydride reduction of l-deoxy-3,4;6,7-di-0-isopropylidene-β-L-gulo-heptulofuranose gave a single product, the heptitol 7-deoxy-l,2;4,5-di-0-isopropylidene- L-glycero-D-gluco-heptitol. This was converted into two novel pyrrolidine amino sugars, l,2,5-trideoxy-2,5-imino-L-glycero-L-allo-heplitol and l,2,5-trideoxy-2,5-imino-L-allitol. The two free hydroxyl groups in the heptitol were converted into leaving groups and one was then displaced selectively with sodium azide. Reduction of the azide functionality gave an amine which cyclised onto the remaining leaving group to form the pyrrolidine framework. Complete deprotection of this product gave l,2,5-trideoxy-2,5-imino-L-glycero-L-allo- heptitol, the structure of which was confirmed by X-ray crystallographic studies on a crystalline derivative. Removal of the primary acetonide from the cyclisation product and subsequent periodate cleavage gave an aldehyde which was then reduced to an alcohol. Deprotection then gave the second pyrrolidine amino sugar l,2,5-trideoxy-2,5-imino-L-allitol. The effect of all five target compounds on eleven human liver glycosidase enzymes was investigated, and these results are also reported.

The purpose of this work was the preparation of specifically blocked D-glucose derivatives with a free hydroxyl group on the anomeric carbon (C-1).

No description available.

No description available.

No description available.

This study concerns an investigation of nitrous acid deamination of various amino sugar derivatives. Deamination reagents have also been used for the diazotization of aromatic compounds. Nitrous acid deamination was used in the deamination of amino acids pinacolic amino alcohols and amino sugars.

Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 104-124). Also available on the World Wide Web.