Isohexide derivatives

H Chemical Shifts for the Ring System of Isohexide Derivatives Chemical shifts... 

Four X-ray investigations of isohexide derivatives have been published.39-42 The oldest of them gave very little information about structural details. Two crystallographically independent molecules of 1,4 3,6-dianhydro-2-0-(p-bromophenylsulfonyl)-D-glucitol 5-nitrate (30), having the same conformation, are in the asymmetric unit. 

The continuous worldwide application of isosorbide dinitrate and, since the early eighties, of isosorbide 5-mononitrate also, has given rise to a very great number of publications on different aspects of these drugs. It would be beyond the scope of this report to include all of the work on these two important compounds. The present synopsis is therefore restricted to other novel isohexide derivatives and to some new pharmaceutical applications of known compounds. 

Among 138 examples of various sulfamoyl compounds, three isohexide derivatives were mentioned. Their preparation started from corresponding free hydroxyl compounds by reaction with sulfamoyl chloride, which itself had been generated in situ from chlorosulfonyl isocyanate. They were claimed for treatment of chronic arthritis and osteoporosis.221 ... 

Wu, J., Eduard, P., Thiyagarajan, S.etal. (2011) Isohexide derivatives from renewable resources as chiral building blocks. ChemSusChem, 4 (5), 599-603. 

Generally, lower shift values (downfield shifts) are measured for groups in the exo, compared with those in the endo, position.21 29 For mixed 2,5-disub-stituted isohexides, the situation is not so clear in each case.21 The 13C-chemical shifts of the isohexides and selected derivatives are summarized in Table VII. 

C Chemical Shifts of Isohexides and Derivatives in CDCl, versus Me4 Si as Internal Standard... 

As a consequence, in most cases, the preparation of dialkyl isohexides is described in the literature. Some mono ethers have also been prepared, bearing different acyl groups on the second hydroxyl group of the ring system. Only very few examples of monoalkyl derivatives lacking further substituents are known. 

Mesylates and tosylates of isosorbide and isomannide undergo nucleophilic displacement with a number of primary and secondary amines, as described in a pharmaceutically oriented publication.131 Several patents describe the preparation of numerous aminodeoxyisohexide derivatives bearing an additional nitric ester group at the 2 or 5 position of the isohexide ring-system.142 144 207 Among these, purines and purine-alkylamines were... 

An oxidized stage of isohexide nitrates, wherein the remaining hydroxyl group is transformed into the ketone, gives rise to a number of derivatives 161, such as oximes, semicarbazones, acyclic and cyclic acetals, and hydra-zones.154 Among them, 3-amino-2-hydroxypropyl-substituted oxime ethers... 

Isohexides exhibit excellent properties as plasticizers for polyvinyl alcohol polymers.2 Compounds obtained from isosorbide and trialkylaluminum proved to be highly active cocatalysts for polymerization of alkenes. Such derivatives, which were supposed to be oligomeric O-aluminum-isosorbides, are of glass-like appearance and exhibit pyrophoric properties.255 Isosorbide is a component of mixtures used for water-based pigment inks, having excellent dispersion stability, which is necessary for ink-jet printing.256 257... 

Table 9.5 Properties of the homo-polyesters derived from isohexides and various aliphatic diacids.

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