Inositols anhydro

Inosine, 6-benzyloxy-9- -D-ribofuranosyl-2-dimethylamino-hydrogenolysis, 5, 558 Inosine, 2 -deoxy-alkylation, 5, 538 Inosine, 6-phenacylthio-dethiation, S, 559 Inosine 5 -monophosphate biosynthesis, 1, 88 Inosines, thio-synthesis, 5, 584 Inositol, D-l,4-anhydro-synthesis, 1, 416 Inositols synthesis, 1, 416 Insecticides... 

Scheme 6. — Reaction of ConduritoJ Epoxide (Anhydro-inositol, Hydroxyl groups omitted) with / - and a-Specific Glycosidase, Respectively.

Qualitative relaxation-studies have also been reported for an extensive series of derivatives of inositols, pentopyranoses, l,6-anhydro-/3-D-hexopyranoses, furanoses, and septanoses. In all instances, the experimentally determined Ri(ns) values reflect the anticipated geometry. For the furanose derivatives especially, they provide a better means for distinguishing between epimeric pairs than the relatively ambiguous interpretation of coupling-constant data. 

In the inositol series Angyal and co-workers 9- 4 have synthesized u number of epoxides by the same approach. For instance, 3-O-methyl-4-0-tosyl- +)-inoeital yielded 4,o,6tri-0acetyl -2,3-anhydro 10... 

Synthesis of 1,2-anhydro-alfo-inosito) was accomplished from 3,4 5.6-di-0-tacpropyiidene-aUo-inositol in four steps, as indicated in Kq. (249). Certain isomeric anhydroinositols were prepared analogously.33... 

The phenomenon of epoxide migration is directly demonstrable with l,2-anhydro-oUo-inogitol,S4 which gives on treatment with dilute alkali at room temperature the isomeric substance ),2-anhydro eo-inositol (Eq, 250). 

Partial benzylation with powdered potassium hydroxide as a base and toluene as a solvent was used some 50 years ago for the preparation of 1,6-anhydro-2,4-0-benzyl-P-D-glucopyranose [79]. Since that time, other solvents, such as benzene [80-82], 1,4-dioxane-toluene mixtures [83, 84], or excess benzyl chloride [82, 85] were used as well, with apparent effects on the regioselectivity. Thus, the axially oriented secondary hydroxyl group of lL-l,2,3,4-tetra-0-benzyl-c/i ro-inositol is more reactive than the equatorial one using benzyl chloride alone (ratio of 79 21), whereas the opposite is true (35 65) in benzene as a solvent [82]. Benzylation of myo-inositol derivatives in the latter solvent was also described [80, 81, 86]. 

Sequoyitol, which is optically inactive, was presumed to be one of the meso forms, and this presumption was eventually verified by the finding that the infrared spectrum of its pentaacetate differs from those of the (optically active) bornesitol pentaacetate and ononitol pentaacetate.66 Many unsuccessful attempts were made to decide between the two possibilities (LXXI and LXXII) by indirect means,78 83 by synthesis,164 and by degradation.68 Proof that sequoyitol is actually 5-O-methyl-myo-inositol (LXXI) was finally obtained by synthesizing it from (+)-pinitol.M The only myoinositol methyl ethers which could be derived from pinitol by the inversion of one of its hydroxyl groups are LXXI and LXXIV formula LXXIV is excluded because it must be optically active. The synthesis of sequoyitol from (+)-l, 2-anhydro-neoinositol (see p. 183) confirms the formula LXXI.7-166... 

An unequivocal synthesis of the racemate of LXXIV was achieved by treating 5,6-anhydro-aZZo-inositol with sodium methoxide7 (see p. 183). The pentaacetate of LXXIV has the same infrared spectrum as the pentaacetate of (+)-ononitol, and hence the ononitols are the 4-0-methyl- ra/o-inositols. 

Anhydro and 1,4-anhydroinositols are not known, but 1,2-anhy-droinositols are readily prepared by two methods (a) the action of bases on tosyl derivatives in which an adjacent hydroxyl group is frans-situated, and (b) treatment of cyclohexenetetrols with peracids. The former method has been used by Angyal and coworkers,7 149 the latter by Nakajima and coworkers.34 As a result of their work, six out of the ten possible diastereo-meric anhydrides are now known. On p. 168, the preparation of (+)-l,2-anhydro-3,4 5,6-di-O-isopropylidene-aZZo-inositol (LXII) from the mono-tosyl derivative of di-O-isopropylidene-feyo-inositol has already been mentioned careful, acidic hydrolysis of LXII gives (+)-l,2-anhydro-oZta-inositol (XCIX), the most readily available of the anhydroinositols.7 Similarly, the diisopropylidene acetal of 1-O-tosyl-epf-inositol gives 5,6-an-hydro-aZZo-inositol (CIII).7 The trans-1,2-di-0-tosyl compounds react in... 

Only one example is available of the use of a preformed true anhydro-inositol for inosamine synthesis (+)-l, 2-anhydro-3,4 5,6-di-0-isopropyl-idene-aZZo-inositol (CXXVII) yields (-j-)-neo-inosamine-l (CXXVIII) and Zero-inosamine-3 (/ewo-inosamine-o, CXXIX) on ammonolysis and hydrolysis.214 However, the epoxide CXXX and its pentaacetate CXXX (see below) have been treated with ammonia and with a variety of primary and... 

Enhancement Factors 1 for Paper-chromatographic Mobility of Alditols, Inositols, and Anhydro Compounds by Phenylboronic Acid... 

Alditol Enhancement factor" Inositols and anhydro compounds Enhancement factor"... 

Epoxide formation. Australian workers used the strongly basic Deacidite FF for conversion of 1-O-p-toluenesulfonylinositol (1) into l,2-anhydro-( )-inositol (2). Use of aqueous alkali led to 1,2-anhydromyoinositol (3) by epoxide migration. ... 

A number of tetraphosphate analogues, e.g. 24, have been prepared with a view to increasing cell membrane permeation properties. Routes to 3,4,5,6-tetrakis-phosphates, e.g. 25, of DL-l,2-dideoxy-l,2-difluoro-mjo-inositol and dl-1,2-dideoxy-1,2-difluoro-5cj//o-inositol have been reported.The fluoro substituents were introduced using DAST to displace hydroxy groups. However, the difluorina-tion could not be achieved in one step due to competing formation of a 1,4-anhydro derivative. The synthesis, from wjo-inositol monobenzoate derivatives, of all four... 

Idose, 3,6-anhydro-L-, 52 Inositol, aminodeoxy-meso-, 53 Inulin, 306... 

It should be more convenient to prepare the Dirpentol by hydrogenolysis of meso-2,3-anhydro-aZZo-inositol (36) and to prepare the (- -) or (—) pentols by hydrogenolysis of suitable forms of 1,2-anhydro-aZZo-inositol (37). In the latter reaction, ZaZo-quercitol would also be formed. 

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. ... 

The di-O-isopropylidene acetal (46), of 1,2-anhydro-cfs-inositol on reaction with a-toluenethiol gave the <8-benzyl derivative (47) which, on... 

When 1,2-anhydro-a(Zo-inositol di-O-isopropylene acetal was treated with a-toluene-thiol, using the same procedure, a colorless crystalline product, m.p. 103-104°, was obtained in small yield. This material was shown, by nuclear magnetic resonance, to be an unexpected byproduct, tribenzyl trithioorthoformate, resulting from the interaction of aqueous sodium a-toluenethioxide with the chloroform used as the extraction solvent. 

In their 1956 article,McCasIand and Reeves tentatively assigned the configuration dl(1235/46) to their bromoquercitol pentaacetate (m.p. 151.5-152.5°) from epi-inositol. For this reason, when Nakajima prepared the same product (m.p. 148-149°, uncorr.) in 1961 from 1,2-anhydro-ept-inositol, he did not recognize that the two products are identical. Both actually have the same configuration, namely, DL (1234/56). 

Reaction of the (-f)-di-O-isopropylidene acetal (96) of 1,2-anhydro-a21o-inositol with methyl potassium xanthate gave a yellow, crystalline mixture of the two diastereomeric trithiocarbonates (95 and 97), separated by... 

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