Mannitol anhydro

Sugihara and Schmidt49 reported the isolation of 2,5-anhydro-D-glucitol in crystalline form its preparation on a relatively large scale has been described in the patent literature,50 and consists in the thermal dehydration of D-mannitol. The process leads to the formation of 1,4-anhydro-D-mannitol, 1,5-anhydro-D-mannitol, 1,4 3,6-dianhydro-D-mannitol, and 2,5-anhydro-D-glucitol, which is isolated as the crystalline 1,3-O-isopropyIidene derivative (35). 

Anhydro-D-mannitol 2.6- Anhydro-D-mannitol (1,5-anhydro-D-mannitol) 136-7... 

Alditols and Cyclitols.- 2,5-Anhydro-D-mannitol, 1,5-anhydro-D-glucitol, 1,2 i, 5-dianhydro-3-0- (4-pheny Ibenzoy 1 )-xylltol, and... 

The synthesis of all positional isomers of partially methylated-acetylated or methylated-benzoylated derivatives of 1,4-anhydro-D-xylitol, 1,4-anhydro-L-fucitol, 1,4-anhydro-D-ribitol, 1,5-anhydro-D-mannitol, 1,5-anhydro-D-gJu-citol, and IjS-anhydro-D-galactitoP" have been described. The compounds should be useful as standards for determining the primary structure of polysaccharides after reductive cleavage. 

Fakes et al. [1.152] described the moisture sorption behavior of mannitol, anhydro-lactase, sucrose, D-(+)-trehalose, dextran 40 and providone (PVP K24) before and after freeze-drying in a 10% solution. All products where frozen at 0.50 °C/min to -40 °C and freeze-dried at 0.13 mbar and Tsh = -15 °C for 28 h. SD lasted for 14 h at Tsh = 25 °C. Table 1.10.5 shows the moisture contents before and after freeze-dying. Figure 1.69.2 present the weight change in % of sucose, trehalose, mannitol and lac-... 

Aliphatic fluorodenitration has also been applied to mononitro compounds, specifically to an a-nitroepoxide Thus, l,2-anhydro-3 4 5,6-di-O isopropyli dene-1-C-nitro D mannitol and labeled potassium bifluonde give 2-deoxy-2-fluo-ro-3,4 5,6-di-O-isopropylidene aldehydo D glucose [J03, 104] (equation 30)... 

Amino-1,5-anhydro-1 -deoxy-D-mannitol or 1,5-dideoxy-1,5-imino-D-mannitol trivial name deoxymannojirimycin... 

S)-1,5-Anhydro-3,4,6-tri-0-benzyl-1 -C,2-0-(ophenylenemethylene)-D-mannitol Note. The isomeric chromene would be named as a 2-0,1 -C-substituted system. 

Support for this result was obtained from the taste of 1,5-anhydrohexitols, which, only for purposes of comparison, can be regarded as 1-deoxyal-dopyranoses. 1,5-Anhydro-D-glucitol (that is, the incorrectly named 1-deoxy-D-glucopyranose ) (14), 1,5-anhydro-D-mannitol ( 1-deoxy-D-mannopyranose or 2-deoxy-D-fructopyranose ) (15), and 1,5-anhydro-D-galactitol ( l-deoxy-o-galactopyranose ) (16) are all purely sweet, without any trace of bitterness. Furthermore, the complete absence of bitterness of 1,5-anhydromannitol (16) clearly indicates that the anomeric... 

When Shallenberger and coworkers attempted to explain the sweetness of /8-D-fructopyranose, they intuitively assigned the anomeric 2-hydroxyl group as AH and the oxygen atom of the 2-(hydroxymethyl) substituent as B. This assignment has since been supported by Lindley and Birch. It was shown that 1,5-anhydro-D-mannitol (15, 2-deoxy-D-fructopyranose ) and jS-D-arabinopyranose (22) (in both of which, one of the AH or B units... 

Ana,6s (2 AM6S (where I = a-L-iduronic acid, ANA6S = 2-acetamido-2-deoxy-a-D-glucopyranose 6-sulfate, G = / -D-glucuronic acid, and AMes = 2,5-anhydro-D-mannitol 6-sulfate, the last arising from 2-deoxy-... 

Brigl and Griiner45 reported the isolation of three products when 1,6-di-O-benzoyl-D-mannitol (29) was heated in boiling 1,1,2,2-tet-rachloroethane in the presence of p-toluenesulfonic acid as the catalyst. These compounds were assigned mono- and di-anhydro structures, and were later shown by Hockett and coworkers46,47 to be 1,4-anhydro-D-mannitol dibenzoate (30), l,4 3,6-dianhydro-D-man-nitol dibenzoate (31), and 2,5-anhydro-l,6-di-0-benzoyl-D-glucitol (32). The latter compound, which can be readily isolated from the... 

Intramolecular cyclization can also be effected with acyclic intermediates derived from such readily available alditols as D-mannitol. Kuszmann and Vargha63 reported the formation of 2,5-anhydro-l,6-dibromo-l,6-dideoxy-4-0-(methylsulfonyl)-D-glucitol (63), in 73% yield, by boiling 3,5-di-0-acetyl-l,6-dibromo-l,6-dideoxy-2,4-di-0-... 

Miiller and Vargha65 reported that treatment of 1,6-di-O-benzoyl-D-mannitol (29) with p-toluenesulfonyl chloride gave 2,5-anhydro-l,6-di-0-benzoyl-3,4-di-0-p-tolylsulfonyl-D-glucitol (67). The formation of this compound may be the result of a favored p-toluenesulfonyla-tion at the 2(5)-hydroxyl group, followed by intramolecular cycliza-tion and subsequent esterification by the excess of the reagent. This... 

Intramolecular displacement of primary sulfonyloxy or halide groups in derivatives of D-mannitol can also be brought about under basic conditions, albeit in low yield. Treatment of l,6-di-0-(methyl-sulfonyl)-D-mannitol (78), or the corresponding dichloride derivative, with sodium methoxide gave 2,5 3,6-dianhydro-D-glucitol74 (79). Treatment of the latter with hydrochloric acid at 100° in a sealed tube gave the 6-chloro-6-deoxy derivative (80), which was converted into the known 2,5-anhydro-l,6-di-0-benzoyl-D-glucitol45 47 (32). The sequence 78-80 is of interest in the context of C-/3-D-nucleoside precursors, but it suffers from the fact that yields are low. 

Ring contraction ofglycals.1 The oxidative ring contraction of cyclic alkenes (4,492-493) can be applied to protected glycals. Thus oxidation of the D-glucal 1 with TTN in CH3CN provides the 2,5-anhydro-D-manose 2, whose structure was established by conversion to the 2,5-anhydro-D-mannitol derivative (3). 

Styracitol, or 1,5-anhydro-D-mannitol (XLI), discovered in Styrax Obassia Sieb. et Zucc. by Asahina45 and subsequently synthesized by... 

Ethyl tetraacetyl-l-thio-/S-D-mannopyranoside to l,5-anhydro-i>-mannitol... 

Anhydro-D-mannitol is also obtained by a novel route from 1,6-dibenzoyl-D-mannitol. When this compound is heated with p-tolu-enesulfonic acid in acetylene tetrachloride, it suffers partial dehydration and one of the products is a dibenzoyl derivative of mannitan. On debenzoylation of this substance it yields crystalline 1,4-anhydro-D-mannitol.67 The formation of dibenzoyl-1,4-anhydro-D-mannitol has involved the migration of at least one benzoyl group and Hockett and coworkers6 believe that the initial product is either 2,6- or 3,6-dibenzoyl-1,4-anhydro-D-mannitol. 

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... 

Crystalline 1,4-anhydro-D-sorbitol is of much more recent origin than 1,4-anhydro-D-mannitol, inasmuch as its preparation was first recorded in 1946.10 It was obtained by the restricted dehydration of D-sorbitol and has been given the trivial name arlitan. Two groups of workers simultaneously effected proof of its constitution. Hockett and coworkers11 treated the anhydride with lead tetraacetate and since its rate of oxidation coincided with that of ethyl D-galactofuranoside and since one molecular proportion of formaldehyde was formed, the authors concluded that the ring must involve Cl and C4 of a hexitol chain. Assuming that no other carbon atoms are involved, sorbitan is either 1,4-anhydro-D-sorbitol or 1,4-anhydro-D-dulcitol (Walden inversion at C4 of the sorbitol molecule). They therefore synthesized 3,6-anhydro-D-dulcitol (enantio-morphous with 1,4-anhydro-L-dulcitol) but found it to be different from arlitan. 

Freudenberg and Rogers24 then offered evidence that styracitol was 1,5-anhydro-D-mannitol (XXV), which was based on the difference in... 

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