Deoxyribose (DR)

Deoxyribose is a monosaccharide with idealized formula H-(C=O)-(CH2)-(CHOH)3-H. Its name indicates that it is a deoxy sugar, meaning that it is derived from the sugar ribose by loss of an oxygen atom. Since the pentose sugars arabinose and ribose only differ by the stereochemistry at C2', 2-deoxyribose and 2-deoxyarabinose are equivalent, although the latter term is rarely used because ribose, not arabinose, is the precursor to deoxyribose. Several isomers exist with the formula H-(C=O)-(CH2)-(CHOH)3-H, but in deoxyribose all the hydroxyl groups are on the same side in the Fischer projection. The term "2-deoxyribose" may refer to either of two enantiomers: the biologically important D-2-deoxyribose and to the rarely encountered mirror image L-2-deoxyribose. D-2-Deoxyribose is a precursor to the nucleic acid DNA. 2-Deoxyribose is an aldopentose, that is, a monosaccharide with five carbon atoms and having an aldehyde functional group.