Deoxyribose, or more precisely
2-deoxyribose, is a
monosaccharide with idealized formula H-(C=O)-(CH
2)-(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.