Cyclitol

inositol is a common cyclitol.

In organic chemistry, a cyclitol is a cycloalkane containing at least three hydroxyl, each attached to a different ring carbon atom. ^[1] Most commonly, cyclitol refers to cyclic sugar alcohol. ^[2] Cyclitols and their derivatives are some of the compatible solutes that are formed in a plant as a response to salt or water stress. Cyclitols are minor components of trees. ^[3] Some cyclitols (e.g. quinic or shikimic acid) are parts of hydrolysable tannins.

Even simple cyclitols can be complicated by different isomeric possibilies. For example, there are three different constitutional isomers of cyclohexanetriol: 1,2,3-, 1,2,4-, and 1,3,5-. And even though there is only one reasonably stable constitutional isomer of cyclohexanehexol (inositol), there are nine stereoisomers possible.

Naturally occurring cyclitols

Unsubstituted

• Conduritol, or cyclohex-5-ene-1,2,3,4-tetrol; two out of ten possible isomers.
• Inositol, or cyclohexane-1,2,3,4,5,6-hexol; four out of nine possible isomers.
• Cyclohexanetetrol ^[4]

Substituted

• Bornesitol; (1R,2R,3S,4S,5R,6S)-6-methoxycyclohexane-1,2,3,4,5-pentol; D-(−)-O-methyl-myo-inositol
• Pinitol; (1S,2S,4S,5R)-6-methoxycyclohexane-1,2,3,4,5-pentol; 3-O-methyl-D-chiro-inositol
• Ononitol; (1R,2S,3S,4S,5S,6S)-6-methoxycyclohexane-1,2,3,4,5-pentaol; 4-O-methyl-myo-inositol
• Pinpollitol; (1R,2R,3R,4S,5R,6S)-3,6-dimethoxycyclohexane-1,2,4,5-tetraol; di-O-methyl-(+)-chiro-inositol
• Quebrachitol; (1R,2S,4S,5R)-6-methoxycyclohexane-1,2,3,4,5-pentol; 2-0-methyl-chiro-inositol
• Quinic acid; (1S,3R,4S,5R)-1,3,4,5-tetrahydroxycyclohexanecarboxylic acid
• Shikimic acid; (3R,4S,5R)-3,4,5-trihydroxycyclohex-1-ene-1-carboxylic acid
• Valienol; (1S,2S,3S,4R)-5-(Hydroxymethyl)cyclohex-5-ene-1,2,3,4-tetrol
• Viscumitol (1R,2S,3R,4S,5R,6S)-5,6-dimethoxycyclohexane-1,2,3,4-tetraol; 1,2-di-O-methyl-muco-inositol

Glycosides

• Ciceritol, a pinitol digalactoside

Phosphates

• Phytic acid; (1R,2S,3r,4R,5S,6s)-cyclohexane-1,2,3,4,5,6-hexayl hexakis[dihydrogen(phosphate)]; inositol hexakisphosphate

Other cyclitols

• 1,2,3,4-Cyclohexanetetrol ^[5]
• 1,2,3,4,5-Cyclopentanepentol

Applications

Aside from their utility to plants, cyclitols are useful as precursors to synthetic materials. ^[6]

Analysis methods

Théodore Posternak and others described the separation of cyclitols by paper chromatography using three methods of development: Tollens' reagents, the Meillère reagent (based on the Scherer-Gallois reaction), and digestion by Acetobacter suboxydans followed by Tollens' reagent. ^[7]

Further reading

Nomenclature for cyclitol stereoisomers:CON and CBN IUPAC Commissions on Nomenclature (1968): "The Nomenclature of Cyclitols - Tentative Rules". European Journal of Biochemistry, volume 5, pages 1-12. doi : 10.1111/j.1432-1033.1968.tb00328.x

See also

• Aminocyclitol

References

1. IUPAC , Compendium of Chemical Terminology , 5th ed. (the "Gold Book") (2025). Online version: (2006–) " Cyclitols ". doi : 10.1351/goldbook.C01493
2. Vovener de Verlands, Edmond; Hong, Zonglie; Nelson, Andrew S. (2025). "Sugar alcohols in plants: implications for enhancing tree seedlings drought tolerance and production strategies". BMC Plant Biology. 28 (1) 891. Bibcode:2025BMCPB..25..891E. doi: 10.1186/s12870-025-06860-9 . PMC   12239448 . PMID   40634904.
3. Hoch, G.; Richter, A.; Körner, Ch. (2003). "Non-structural carbon compounds in temperate forest trees". Plant, Cell & Environment. 26 (7): 1067–1081. Bibcode:2003PCEnv..26.1067H. doi:10.1046/j.0016-8025.2003.01032.x.
4. J. S. Craigie (1969): "Some Salinity-Induced Changes in Growth, Pigments, and Cyclohexanetetrol Content of Monochrysis lutheri". Journal of the Fisheries Research Board of Canada, volume 26, issue 11, pages 2959-2967. doi : 10.1139/f69-282
5. Nihat Akbulut and Metin Balci (1988): "A new and stereospecific synthesis of cyclitols: (1,2,4/3)-, (1,2/3,4)-, and (1,3/2,4)-cyclohexanetetrols". Journal of Organic Chemistry, volume 53, issue 14, pages 3338-3342. doi : 10.1021/jo00249a039
6. Ferrier, Robert J.; Middleton, Sydney (1993). "The conversion of carbohydrate derivatives into functionalized cyclohexanes and cyclopentanes". Chemical Reviews. 93 (8): 2779–2831. doi:10.1021/cr00024a008.
7. Th. Posternak, D. Reymond, W. Haerdi (1955): "Recherches dans la série des cyclitols XX. Chromatographie sur papier de cyclitols et de cycloses". Helvetica Chimica Acta volume 38, issue 1, pages 191-194 doi : 10.1002/hlca.19550380122