Neo-Inositol

An interesting example of the effectiveness of different reagents for 0-nitration can be seen during the synthesis of neo-inositol-based nitrate ester explosives. l,4-Dideoxy-l,4-dinitro-neo-inositol (15), a compound readily prepared from the condensation of nitromethane and glyoxal in the presence of base,undergoes conversion to the tetranitrate ester (16) on... 

Occasionally, a per-O-acetylated amine can be used in the synthesis of a partially acetylated compound. For example, 2-amino-2-deoxy-neo-inositol pentaacetate, which was prepared from hygromycin A, was converted by deamination into 1,2,3,4,6-penta-O-acetyl-myo-inositol.226... 

Barker and Shaw80 have recently shown that compounds which contain a cis-cis-1,2,3-triol system, in a six-membered ring, form relatively stable complexes with the periodate ion at a pH of about 7. Steric considerations suggest that the axial-equatorial-axial conformation is required. As expected, one mole of neo-inositol forms a complex with two moles of periodate, but rac-, muco-, and mi/o-inositols form no such complexes. Although mj/o-inositol has a cis-cis-1,2,3-triol system, the conformation XL required... 

Finally, new studies often illuminate the importance of pathways and metabolites that simply were not initially observed in first-generation studies. A great example of this is the study of Martin et al. (2000) which showed that the Ins phosphate pathways in the amoeba Entamoeba histolytic in fact use neo-inositol and not ///vd-inositol as the backbone for Ins phosphate synthesis. This suggests that a reanalysis of basic assumptions, leading to a new synthesis of the nature and role of these pathways, might be achieved in the coming years. 

Martin, J.-B., Laussmann, T., Bakker-Grunwald, T., Vogel, G., and Klein, G., 2000, neo-inositol polyphosphates in the amoeba Entamoeba histolytica. J. Biol. Chem. 275 10134-10410. 

If two axial hydroxyl groups in a molecule are sterically equivalent, they are oxidized at the same rate. Thus, the oxidation of epi-inositol (32) gives racemic ( )-epf-inosose (33, 34), which is also obtained by the oxidation of mi/o-inositol (23) with nitric acid. As expected, neo-inositol (35) yields pure neo-inosose (36) on catalytic oxidation. Hydrogenation of the... 

Of especial interest is the extremely facile dehydroacetylation of structures that contain a nitro group flanked on both sides by acetoxyl groups. Deoxynitroinositol pentaacetates (185 and epimers) and 1,4-dideoxy-l,4-dinitro-neo-inositol tetraacetate (187) readily lose three molecules of acetic acid per molecule by the action of pyridine, to... 

A. Maras, H. Secen, Y. Sutbeyaz, and M. Balci, Convenient synthesis of (+)-ta/o-quercitol (1-deoxy-neo-inositol) and (+) vibo-quercitol (1-deoxy-myo-inositol via ene reaction of singlet oxygen, J. Org. Chem., 63 (1998) 2039-2041. 

In the latter reaction, however, the predominant product is (+)-toZo-quercitol (44). neo-Quercitol is 5-deoxy-m2/o-inositol perhaps some preparation from myo-inositol can be devised. The configuration wieso(15/234) was established by correlation with neo-inositol (34). 

The (-I-) enantiomorph was obtained by dehalogenation of appropriate (123/456) stereoisomers of chloro-, bromo-, or iodo-quercitol (40) also, by hydrogenolysis of (-[-)-l,2-anhydro-neo-inositol (38). In the latter reaction, a little neo-quercitol is formed. ... 

Three stereoisomeric inositols were prepared from the highly functionalized derivative 215 which can be derived from 214 in one step by the reaction with KMn04 (Scheme 4-13).82 Treatment of 215 with AI2O3 in an aqueous medium afforded stereoselectively the ketoalcohol 216 in 85% yield, which was converted efficiently to allo-inositol (217) essentially as a single product. The epoxy diol 215 was converted under basic conditions to D-chiro-inositol (125) with more than 95% selectivity by attack of the hydroxide ion on one side of the epoxide carbon atom while its treatment under acidic conditions furnished neo-inositol (219) as a minor product along with 125 (3 7) resulting from the attack of H2O from the other side. 

Hygromycin. 5-Deoxy-5-[[3-[4-(<6-deoxy-d-D-arabino.hexo/ttranos-S-ulos-l-yt)oxy]-3-hydroxyphenyl]-2-methyl-I-oxo-2-propenyt]amino]-l,2-0-methylene-D-neo-inositol homomycin hygromycin A 1703-18B St-4331. C23Hj,NO mol wt 511.47. C 54.01%. H 5.71%, N 2.74%. O 37.54%. Antibiotic substance produced by Streptomyces hygroscopicus (Jensen) Waksman Henrici, from forest soil near Indianapolis, Ind R L. Mann ef of.. Antibiot. ... 

The trithiocarbonates may prove useful as intermediates for the synthesis of sugar dithiols from epoxides. Ring opening by reductive cleavage with lithium aluminum hydride gives excellent results with aliphatic and ahcyclic trithiocarbonates. When both carbon atoms are secondary, the product is a iraws-dithiol for example, cyclohexene oxide, which is converted into a irans-trithiocarbonate, gives, on reduction, cyclo-hexane-1,2-dithiol. The reaction has been used in the cyclitol series for the preparation of 1,2-dithio-neo-inositol and 1,2-dithio-ir-inositol, from 1,2-anhydro-alZo-inositol. The inositol trithiocarbonates show pronounced Cotton effects in their optical rotatory-dispersion spectra. 

Laird, M.H., Allen, H.J., Danielli, J.F. and Winzier, R.J. (1 976) The identification of phosphorylated neo-inositol as an anionic component of the Amoeba cell surface. Archives of Biochemistry and Biophysics 1 75, 384-391. 

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