Alditole i anhydroalditole

Alditols belong to the group of acyclic polyols. Formally, they are obtained from the aldose or ketose by reduction of the carbonyl group. Single or double dehydratation of alditols provides the cyclic compounds named anhydroalditols and dianhydroalditols, respectively. Alditols and anhydroalditols are widespread in both animal and plant kingdoms. They are in human blood and urine, and in the amniotic and cerebrospinal fluids. Herein the applications of alditols and anhydroalditols in medicine and human nutrition are presented. (For example d-mannitol is used as a diuretic agent or in osmotherapy to reduce acutely raised intracranial pressure; isosorbide mononitrate is used against angina pectoris. Xylitol (pentitol) can counteract several diseases, among others, the acute otitis media, osteoporosis, tooth decay and helps the remineralization of teeth, thanks to that it found use as an additive to chewing gum [4]. Most alditols including d-mannitol, d-glucitol and 1,4-anhydro-d,l-galactitol, are used as sweeteners and as well as additives for low caloric food or as diets for diabeties. Although they show lower sweetness than glucose or saccharose, their great advantage is that it does not cause a rapid increase of glucose level in blood [5,6]. While nitrates 1,4:3,6-dianhydro-d-mannitol and 1,4:3,6-dianhydro-d-glucitol thanks to the ability of blood vessels relaxant are commonly used for years in the treatment of heart diseases and blood system [10]). It is demonstrated that introduction of alditol or anhydroalditol to biologically active compound may improve its activity. Anhydroalditols are also useful substrates for the stereospecific synthesis of bicyclic compounds. Additionally, alditols and anhydroalditols are promising monomers for synthesis of polymers with interesting properties. Finally, methods of alditols and anhydroalditols syntheses are presented. Among them we consider: cyclization in an acid medium involving intramolecular dehydration, SN2 reaction with suitable leaving groups, deamination reaction combined with reduction, reduction of glycosyl halide, tioglycoside and glycoside, and addition of water or hydrogen to the double bond in glycals.