Identification and Related Records
- 【CAS Registry number】
- 【Molecular Formula】
- C20H30O (Products with the same molecular formula)
Chemical and Physical Properties
- Practically insoluble in water or glycerol; soluble in absolute alcohol, methanol, chloroform, ether, fats and oils
Sol in ethanol and acetone and benzene
- 【Spectral properties】
- Index of refraction: 1.6410 at 20 deg C/D (calculated form refractive indexes of 20-70% solutions in mineral oil); max absorption: 324-325 nm (E=1,835, 1%, 1 cm)
IR: 16101 (Sadtler Research Laboratories Prism Collection)
MASS: 68282 (NIST/EPA/MSDC Mass Spectral Database 1990 version)
IR: 16101 (Sadtler Research Laboratories IR prism collection)
- 【Computed Properties】
- Molecular Weight:286.4516 [g/mol]
Rotatable Bond Count:5
Topological Polar Surface Area:20.2
Heavy Atom Count:21
Isotope Atom Count:0
Defined Atom Stereocenter Count:0
Undefined Atom Stereocenter Count:0
Defined Bond Stereocenter Count:4
Undefined Bond Stereocenter Count:0
Covalently-Bonded Unit Count:1
Feature 3D Acceptor Count:1
Feature 3D Donor Count:1
Feature 3D Hydrophobe Count:3
Feature 3D Ring Count:1
Effective Rotor Count:5.8
Conformer Sampling RMSD:0.8
CID Conformer Count:30
Safety and Handling
- AQUEOUS SOLN (DISPERSIONS) OF OIL-SOLUBLE VIT ARE PREPARED BY THE USE OF AN EMULSIFYING AGENT SUCH AS POLYSORBATE 80.
There are many types of preparations that contain retinol. These include solutions of pure synthetic retinol and concentrates that contain both retinol and vitamin D in various proportions. Vitamin A capsules contain 3 to 15 mg of retinol (10,000 to 50,000 USP vitamin A units) per capsule: tablets are also available. A water-miscible preparation (15 mg/ml; 50,000 USP units/ml) can be given intramuscularly. Tretinoin (all-trans-retinoic acid; RETIN-A) is available for topical use as a solution (0.05%), a cream (0.05 and 0.1%), and a gel (0.025 and 0.01%). Isotretinoin (13-cis-retinoic acid; ACCUTANE) is available for oral use as 10, 20, and 40 mg capsules.
- 【Exposure Standards and Regulations】
- Vitamin A palmitate used as a nutrient and/or dietary supplement in animal drugs, feeds, and related products is generally recognized as safe when used in accordance with good manufacturing or feeding practice. /Vitamin A Palmitate/
Retinol , its cas register number 11103-57-4. It also can be called Aquasol A ; 3,7-Dimethyl-9-(2,6,6-trimethyl-1-cyclohexenyl)-nona-2,4,6,8-tetraen-1-ol ; and Vitamin A . Its classification code are Growth Substances; Micronutrients and Vitamins .
- 【Disposal Methods】
- SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.
Use and Manufacturing
- 【Use and Manufacturing】
- Methods of Manufacturing
... Vitamin A is isolated by liquid-liquid extraction, molecular distillation, and HPLC. Commercial isolation of retinol from natural raw materials starts with fish oils and is conducted in six steps: (1) accumulation of crude vitamin A by the Solexol countercurrent extraction process, (2) short-path distillation of the retinyl esters (200 deg C, 400 Pa), (3) ester saponification (KOH, 60 -70 deg C, 30 minutes, N2), (4) extraction of retinol with ether, (5) short-path distillation of retinol (120 deg C, 400 Pa), and (6) final purification by crystallization from ethyl formate (-35 deg C. With the development of efficient processes for the synthesis of vitamin A on a commercial scale, isolation from natural raw materials has lost importance.
REACTION OF BETA-IONONE AND A PROPARGYL HALIDEU.S. Exports
(1972) 1.83X10+8 GRAMSU.S. Imports
(1972) 8.12X10+8 GRAMS
(1975) 1.30X10+8 GRAMS
(1984) 9.62X10+8 g /Vitamin A and Provitamin A, Synthetic/U.S. Production
(1972) 4.71X10+8 GRAMS
(1975) PROBABLY GREATER THAN 4.54X10+5 GRAMS
(1985) In the United States, commercial production of synthetic retinol is about 1000 tons /9.08X10+8 g/ per year
Biomedical Effects and Toxicity
- 【Pharmacological Action】
- - Organic substances that are required in small amounts for maintenance and growth, but which cannot be manufactured by the human body.
- 【Therapeutic Uses】
- Vitamin A is indicated only for prevention or treatment of vitamin A deficiency states. Vitamin A deficiency may occur as a result of inadequate nutrition or intestinal malabsorption but does not occur in healthy individual receiving an adequate balanced diet. For prophylaxis of vitamin A deficiency, dietary improvement, rather than supplementation, is advisable. For treatment of vitamin A deficiency, supplementation is preferred. /Included in US product labeling/
Recommended intakes may be increased and/or supplementation may be necessary in infants receiving unfortified formula or in individuals with the following conditions (based on documented vitamin A deficiency): Diarrhea; gastrectomy; hyperthyroidism; infections, chronic; intestinal diseases: celiac, diarrhea, topical sprue, regional enteritis; malabsorption syndromes associated with pancreatic insufficiency: pancreatic disease, cystic fibrosis; measles; protein deficiency, severe, stress, prolonged; xerophthalmia. /Included in US product labeling/
Some unusual diets (e.g., reducing diets that drastically restrict food selection, especially the fat-containing foods) may not supply minimum daily recommended intakes of vitamin A. Supplementation is necessary in patients receiving total parenteral nutrition (TPN) or undergoing rapid weight loss or in those with malnutrition, because of inadequate dietary intake.
Recommended intakes for most vitamins and minerals are increased during pregnancy. Many physicians recommend that pregnant women receive multivitamin and mineral supplements, especially those pregnant women who do not consume an adequate diet and those in high-risk categories (i.e., women carrying more than one fetus, heavy cigarette smokers, and alcohol and drug abusers). Taking excessive amounts of a multivitamin and mineral supplement may be harmful to the mother and/or fetus and should be avoided.
Recommended intakes for all vitamins and most minerals are increased during breast feeding.
MEDICATION (VET): Nutritional factor
Vitamin A has been implicated in the differentiation of epithelial tissues. ...A number of investigators have found that vitamin A levels affect ... the incidence of lung cancer in human smokers or tobacco chewers... . Some other types of human cancer such as cancer of the cervix or bladder arise somewhat more frequently in people with low vitamin A intake, Vitamin A analogs or retinoic acid derivatives have been shown to inhibit carcinogenesis in several target organs, especially the mammary gland and the urinary bladder. One explanation is that they restore cell to cell communication, and thus reduce promotion.
- 【Biomedical Effects and Toxicity】
- Vitamin A is distributed into breast milk ... .
Less than 5% of circulating vitamin A is bound to lipoproteins in blood (normal), but may be up to 65% when hepatic stores are saturated because of excessive intake. The amount of vitamin A bound to lipoproteins may be increased in hyperlipoproteinemia. When released from liver, vitamin A is bound to retinol-binding protein (RBP). Most vitamin A circulates in the form of retinol bound to RBP.
Storage: Hepatic (approximately 2 years' adult requirements), with small amounts stored in kidney and lung tissues. Zinc is required for mobilization of vitamin A reserves in the liver.
More than 90% of the intake of preformed vitamin A is in the form of retinol esters, usually as retinyl palmitate. ... When a large excess is ingested, some of the vitamin escapes in the feces. ... Absorption ... is related to that of lipid and is enhanced by bile. ... Aqueous dispersions ... are absorbed more rapidly than are oily solution.
Retinol esters are hydrolyzed in the ... intestine ... Before absorption, followed by reesterification, mainly to the palmitate. ... Significant quantities of vitamin A are also absorbed directly into the circulation.
Retinol bound to retinol-binding protein /alpha-1-globulin/ reaches the cell membrane of various target organs, where the complex binds to specific sites on the cell surface. ... retinol is converted to a retinyl ester. The retinyl ester is then cleaved by a membrane associated hydrolyase, provided that unliganded cytosolic cellular retinol-binding protein is available to accept the retinol. Cellular retinol-binding protein exists in virtually all tissues; exceptions include cardiac and skeletal muscle and the ileal mucosa ... .
Retinol bound to its specific carrier, the retinol binding protein, is known to be the physiological way vitamin A is transported in blood. Unspecific, lipoprotein bound vitamin A has so far only been reported under the condition of hypervitaminosis A. In this investigation vitamin A concentrations in dog plasma are reported (2300 ng/ml), showing for the first time a species which, under physiological conditions, transports most of its vitamin A in plasma as retinyl esters (70%) associated with lipoproteins. This phenomenon might indicate that dogs are less sensitive to the effects of nonspecific delivery of vitamin A than other species. This can open new aspects in retinoid research, especially with regard to hypervitaminosis A - an undesirable side effect of the beneficial use of retinoids in dermatology and oncology. [Schweigert FJ; Int J Vitam Nutr Res 58 (1): 23-5 (1988)] PubMed Abstract
Vitamin A is readily absorbed from healthy gastrointestinal tract (duodenum and jejunum). Absorption of retinol requires presence of bile salts, pancreatic lipase, protein, and dietary fat. Excess, unabsorbed vitamin is excreted in feces. Water-miscible preparations are absorbed more readily than oil solutions.
The Ito cells of the liver represent a special form of fibroblasts, about 80% of the vitamin A content of the normal liver is stored in these cells. Following to the absorption of vitamin A in the intestine, vitamin A (retinol) is transported in chylomicrons and their remnants, and taken up by hepatocytes through receptor-mediated endocytosis. Along with retinol-binding protein vitamin A is transported from the hepatocytes to the Ito cells where it is being stored as lipid droplets. The vitamin A content of the liver tissue in chronic, especially alcoholic liver disease is distinctly lowered. The vitamin A deficiency of the chronic alcoholic liver disease is caused by an accelerated microsomal metabolism of vitamin A. [Korner T et al; Gastroenterol J 49 (3): 93-7 (1989)] PubMed Abstract