Inososes preparation

Treatment with base of the hexos-5-ulose 23, prepared from the acetal 22, gives mainly the inosose 24 with all the hydroxyl groups equatorial (Scheme 5) [13], and similarly the... 

Pentahydroxycyclohexanone Phenylhydrazone(nryo-Inos-ose-2 Phenylhydrazone) 2D-2,3,4,6/5-Pentahydroxycyclohexanone Phenylhydrazone, and 2L-2,4,5,6/3-Pentahydroxycyclohexanone Phenylhydrazone (DL-epi-Inosose Phenylhydrazone). These were prepared by the procedure of Posternak (65), mp 181° and 189°-191°C, respectively. 

D-2,3,5/4,6-Pentahydroxycyclohexanone Phenylhydrazone (D-myo-Inosose-l Phenylhydrazone). This was prepared by the procedure of Magasanik and Chargaff (66), mp 196°-197°C. 

A. I. Fatiadi, Bromine oxidation of inositols for preparation of inosose phenylhydrazones and phenylosazones, Carbohydr. Res., 8 (1968) 141-147. 

The reduction of inososes is a method much used for the preparation of new cyclitols. Catalytic hydrogenation in neutral, aqueous solution yields predominantly the isomer with the newly formed hydroxyl group in the axial position,210 whereas the product from a reduction by sodium amalgam usually contains considerable quantities of both the possible epimers.211 Recently, sodium borohydride has been used for reducing inososes62,68 211 in some cases, but not in others, it provides more of the equatorial isomer than does sodium amalgam. 

Three inosamines were obtained in the course of efforts to synthesize myo-inositol by the nitro-sugar cyclization (see p. 142). However, the methods which have been the most productive of new inosamines are those which are well known as means of preparing amino sugars and aminopolyhydric alcohols, namely, reduction of imine derivatives of carbonyl compounds (in this case, inososes) and ammonolysis of halohydrins and epoxides. 

As mentioned earlier, meso-inositol, and indeed all the inositols, are readily converted to aromatic compounds by oxidation. Posternak found that inosose has the tendency to form phenolic compounds under very mild conditions. On attempted acetylation of inosose with acetic anhydride in the presence of either pyridine or sodium acetate the expected pentaacetate was not obtained the product was 1,2,3,5-tetra-acetoxybenzene (XXXVII). Similarly, the treatment of inosose pentaacetate with boiling acetic anhydride and pyridine or sodium acetate gave the same product. Inosose pentabenzoate was prepared by the use of benzoyl chloride and zinc chloride. Under the influence of pyridine or sodium acetate in acetic acid the pentabenzoate lost two molecules of benzoic acid to give l-hydroxy-2,3,5-tribenzoxybenzene (XXXVIII). 

The Weerman degradation was employed in one of the first preparations of dialdoses, namely of n-f/ireo-tetrodialdose, using the diamide of D-glucaric acid as starting material. An inosose has been degraded to a pentodialdose by way of its disulfone and the Nef reaction, transformation of a 6-deoxy-... 

Finally MacDonald and Fischer have prepared the free ajyZo-pento-dialdose (8) by the sulfone-degradation method. The diethyl dithioacetal of scyllo-inosose (12) was oxidized to the corresponding disulfone which, on treatment with ammonia, gave the dialdose (8). The structure was proved by converting the compound into the bis(ethylene dithioacetal) derivative, which was identical with that obtained from a /io-pentodialdose prepared by a previous method. ... 

A. J. Fatiadi, Preparation of inososes from their phenylhydrazones by use of a cation exchange resin separation of phenylhydrazones from phenylosazones, Carbohydr. Res., 1 (1966) 489-491. 

Post and Anderson prepared the (+)-(13/24) stereoisomer (61) by hydrogenolysis and demethylation of an active inosose methyl ether (65) obtamed by catalytic oxidation of (+)-pinitol (66). The (—) enantiomorph was similarly prepared from (—)-quebrachitol (93, 2-methyl ether). 

A range of mono- and di-anhydro-inositols have been prepared from the isomeric 3,6-dibromocyclohexadienemono-epoxides (6) by conventional transformations via the corresponding anhydroconduritols (7). Another paper reports the synthesis of all the 1,2,3,4- and 1,2,4,5-dianhydro-inositols from inositol disulphonates using sodium methoxide. The hydration of three inososes... 

Two synthetically in iortant variants of the Ferrier carbocyclization reaction have been reported. One is a rearrangement of enol acetate 24 (Scheme 12.7). Reaction of 24 with a stoichiometric amount of Hg salt afforded an organomercurial intermediate 25, which was then treated with NaCl to induce the cyclization affording inosose derivatives 26a and 26b with good stereoselectivity. As biologically inportant myo-inositol derivatives, such as d-myo-inositol phosphates, are optically active, the enol-acetate version of the Ferrier carbocyclization would be effective for the preparation of enantiomerically pure inositol derivatives. 

Yamauchi N, Kakinuma K. Confirmation of m vitro synthesis of 2 deo y-jcyBo inosose. the earliest intermediate in the biosynthesis of 2-deoxysirepiaminc, using cell free preparations of Streptomyces fradiae. ] Antibiot 1992 45 774-780. 

Substituted (eg aminobenzoyl) myoinositol 1,3,4,5-tetralds- and 1,3,4,5,6-poitakis-phosphate and the tritiated derivative 128 have been prepared, the latter by reduction of the corresponding benzyl protected inosose with potassium borotritiide followed 1 l drogoiolysis. 

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