Mannitol deamination

The same anhydride of mannitol has been obtained recently by the deamination of 1-amino-l-desoxy-D-mannitol.8 It is interesting to note that this method of formation of anhydro rings is of fairly general application. Thus 1,4-anhydro-D-sorbitol is obtained from 1-amino-l-desoxy-D-sorbitol. Similarly, methyl 2,3-anhydro-4,6-benzylidene-a-D-manno-pyranoside and methyl 2,3-anhydro-4,6-benzylidene-a-D-allopyranoside9... 

Since no other stereoisomer but that of iditol, mannitol or sorbitol can exist in the as-fused ring series of l,4 3,6-dianhydrohexitols and since amination experiments on the ditosyl derivatives of each isomer have given three different amino derivatives, it is reasonable to assume that the two diamines which have been isolated are of the same configuration as their parent dianhydrohexitols. These two diamines LXXIV and LXXV on treatment with nitrous acid suffered deamination as expected but instead of obtaining in one case isomannide and in the other isosorbide, only one dianhydrohexitol was isolated and that was dian-hydro-L-iditol. The deamination must of course lead to the transitory carbonium cation LXXVIII and this on hydroxylation can take on any of the configurations, L-iditol, D-mannitol or D-sorbitol. That it preferentially takes on the configuration of L-iditol indicates that this is in some ways a more stable structure than the others. This behavior is paralleled... 

On deamination, 2-amino-l,5-anhydro-2-deoxy-l>mannitol gave l,5-anhydro-2-deoxy-D-eryf/iro-3-hexulose as the major product.54 The substitution product 1,5-anhydro-D-glucitol was formed to a small extent, and inversion again predominated, as with other axial amines (60, 72, and methyl 4-amino-4-deoxy-a-D-galactopyranoside) this is in accord with the predominant inversion of configuration reported for deamination, in water-rich media, of simple cyclohexyla-mines,154 and aminodecahydronaphthalenes39 in which the amino group is axial. As discussed previously (see p. 15), the extent of inversion can vary considerably with the nature of the solvent, and steric factors appear to be important in deaminations of per-O-acetyl amines (see pp. 37 and 49). 

The 2,5-diamino-2,5-dideoxy derivatives of l,4 3,6-dianhydro-D-mannitol and -D-glucitol gave, on deamination, the same product, namely, l,4 3,6-dianhydro-L-iditol, in unspecified yield.176 The product presumably arose from carbonium-ion intermediates, which reacted predominantly with solvent on the less hindered, exo sides of the V-shaped molecule. 

The isolation of D-aroWno-hexulose phenylosazone from both 1,4-anhydro-D-mannitol and 1,5-anhydro-D-glucitol indicates that o-aroMno-hexosulose is among the reaction products. - Crude methyl D-glucofurano-sides in dilute sulfuric acid yield pyruvaldehyde, and 2-amino-2-deoxy-D-glucose hydrochloride suffers oxidative deamination. ... 

A synthesis of 3 starting from a conformationally flexible D-mannitol A-Boc bis-aziridine derivative 81 has been reported (Scheme 14). The cyclic carbamate-protected pyrrolidine 82 was obtained from 81 via the regioselective bis-aziridine ring opening with Li2NiBr4, followed by Ag+-promoted intramolecular substitution of the bromide by the N -Boc group in 75% overall yield. Nitrous acid deamination of 82 with isoamyl nitrite led, in 50% yield, to a 1 1 mixture of cyclic carbamate protected pyrrolidines 84 and 85 via the intermediate... 

In the field of aldobiouronic acid derivatives an ingenious method has been devised for the preparation of radioactive disaccharides for use as substrates for o-L-iduronidase, jS-D-glucuronidase, and 2-sulpho-L-iduronate 2-sulphatase. Heparin was cleaved by the deamination procedure and the products were reduced using sodium borotritide to afford access to a-L-idopyranosyluronic and j3-D-glucopyranosyluronic acid derivatives of 2,5-anhydro-D-[l- H]mannitol. Acidic treatment in methanol of the water-soluble polysaccharides of wobaku wood, followed by acetylation, have led to the isolation of the anhydride derivative (53) which was concluded to arise by way of the corresponding aldo-... 

Deamination of N-deacetylated glycosamino-glycans followed by sodium borodeuteride reduction led to pseudo-disaccharides of 2,5-anhydro-D-mannitol or -D-talitol (from D-glucosamine and D-galact-osamine residues respectively) with attached glucuronic acid,... 

Deamination of 2-amino-l,5-anhydro-2-deoxy-D-mannitol with nitrous acid gave principally l,5-anhydro-2-deoxy-D-e/ yt/fru-hex-3-ulose (68%), by migration of H-3, and some 2-deoxy-D-a/ a6/no-hexose (8%) and 1,5-anhydro-D-glucitol (6%). It was established that 2-deoxy-D-nrai>//in-hexose is formed via a hydride-shift mechanism, rather than by acid-catalysed hydration of D-glucal produced by an elimination pathway. 

Deaminative cleavage of heparin and reduction of the resulting disulphated disaccharide with sodium borotritide afforded 2,5-anhydro-4-0-(a-L-idopyran-uronosyl 2-sulphate)-D-[l- H]mannitol 6-sulphate, which was used as the substrate in an assay for a-L-idopyranosyluronic acid 2-sulphate sulphatase. Heparin has been labelled in vivo with S-sulphate. ... 

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