A vitamer of vitamin D and functions as a prehormone and is involved in calcium and phosphorus metabolism
Vitamin D has different vitamers. One of them is the cholecalciferol. Others are ergocalciferol, 22-dihydroergocalciferol, and sitocalciferol. Nevertheless, there are two most predominant vitamers and these are cholecalciferol and ergocalciferol. Similar to other vitamers, the cholecalciferol is a secosteroid, which means it is a steroid with one broken ring. The cleavage on the steroid results when it is exposed to ultraviolet light. The difference of cholecalciferol from ergocalciferol is that the side chain of ergocalciferol contains a double bond between carbon 22 and carbon 23, as well as a methyl group on carbon 24.1
Unlike other vitamins, vitamin D, particularly cholecalciferol is a prehormone and is synthesized naturally by the body. Other vitamins cannot be synthesized de novo and therefore must be ingested or included in the diet. Nevertheless, cholecalciferol is produced in the body but is inactive and will become activated through hydroxylations. The hydroxylation occurs first in the liver and next in the kidneys. The process results in the formation of calcitriol, which is the active form of vitamin D.
IUPAC names: (3β,5Z,7E)-9,10-secocholesta- 5,7,10(19)-trien-3-ol
Chemical formula: C27H44O
- vitamin D3
1Vitamin D. Wikipedia.org. Retrieved from []