Vitamin D refers to a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, iron, magnesium, phosphate, and zinc. In humans, the most important compounds in this group are vitamin D3 (also known as cholecalciferol) and vitamin D2 (ergocalciferol).Cholecalciferol and ergocalciferol can be ingested from the diet and from supplements.Very few foods contain vitamin D; synthesis of vitamin D (specifically cholecalciferol) in the skin is the major natural source of the vitamin. Dermal synthesis of vitamin D from cholesterol is dependent on sun exposure (specifically UVB radiation).
Types:
Several forms (vitamers) of vitamin D exist. The two major forms are vitamin D2 or ergocalciferol, and vitamin D3 or cholecalciferol; vitamin D without a subscript refers to either D2 or D3 or both. These are known collectively as calciferol. Vitamin D2 was chemically characterized in 1931. In 1935, the chemical structure of vitamin D3 was established and proven to result from the ultraviolet irradiation of 7-dehydrocholesterol.
Chemically, the various forms of vitamin D are secosteroids, i.e., steroids in which one of the bonds in the steroid rings is broken. The structural difference between vitamin D2 and vitamin D3 is the side chain of D2 contains a double bond between carbons 22 and 23, and a methyl group on carbon 24.
Product Description
Product Name: Vitamin D2
CAS No.:50-14-6
Molecular Formula: C28H44O
Molecular Weight: 396.6484
Appearance: Light yellow powder or a white crystalline powder.
Application: Mainly used for the prevention and treatment of rickets, osteomalacia, infantile tetany etc.
Packaging:25kg/drum
Specification:
| Items | Specification | Results |
| Characters | A white crystalline powder | A white crystalline powder |
| Melting range | 115.0~119.0ºC | 115.7~116.6ºC |
| Specific optical rotation | +103.0~+106.0ºC | +103.7ºC |
| Organic volatile impurities | Complies | Complies |
| Reducing substances | ≤20ppm | Complies |
| Assay %(by hplc)40MIU/G | 97.0%~103% | 99.6% |
| Identification | Complies | Complie |
Application:
1.Applied in health care product, used as raw materials;
2.Applied in food field, used as pigments, food additives of seasoning;
3.Applied in pharmaceutical field
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