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ChemicalBook--->CAS DataBase List--->50-81-7

50-81-7

50-81-7 Structure

50-81-7 Structure
IdentificationMore
[Name]

L(+)-Ascorbic acid
[CAS]

50-81-7
[Synonyms]

ACIDUM ASCORBICUM
ANTISCORBUTIC FACTOR
ASCOBIC ACID
ASCORBIC ACID, L-(+)
FEMA 2109
L(+)-ASCORBIC ACID
L-ASCORBIC ACID
L-ASCORBIC ACID REAGENT
l-threo-2,3,4,5,6-pentahydroxy-1-hexenoic acid-4-lactone
L-THREOASCORBIC ACID
NP D SOLUTION
VITA-D-CHLOR(TM)
VITAMIN C
3-Keto-L-gulofuranolactone
3-Oxo-L-gulofuranolactone
3-oxo-l-gulofuranolactone(enolform)
Adenex
Allercorb
Antiscorbic vitamin
antiscorbicvitamin
[EINECS(EC#)]

200-066-2
[Molecular Formula]

C6H8O6
[MDL Number]

MFCD03457784
[Molecular Weight]

176.12
[MOL File]

50-81-7.mol
Chemical PropertiesBack Directory
[Appearance]

White crystals
[Melting point ]

190-194 °C (dec.)
[alpha ]

20.5 º (c=10,H2O)
[Boiling point ]

227.71°C (rough estimate)
[density ]

1,65 g/cm3
[FEMA ]

2109
[refractive index ]

21 ° (C=10, H2O)
[storage temp. ]

0-6°C
[solubility ]

H2O: 50 mg/mL at 20 °C, clear, nearly colorless
[form ]

powder
[pka]

4.04, 11.7(at 25℃)
[color ]

white to slightly yellow
[Odor]

Odorless
[PH]

1.0 - 2.5 (25℃, 176g/L in water)
[PH Range]

1 - 2.5
[Stability:]

Stable. May be weakly light or air sensitive. Incompatible with oxidizing agents, alkalies, iron, copper.
[Odor Type]

green
[optical activity]

[α]25/D 19.0 to 23.0°, c = 10% in H2O
[Water Solubility ]

333 g/L (20 ºC)
[Merck ]

14,830
[BRN ]

84272
[BCS Class]

1
[InChIKey]

CIWBSHSKHKDKBQ-JLAZNSOCSA-N
[LogP]

-1.85
[Uses]

vitamin C(50-81-7) is a well-known anti-oxidant. Its effect on free-radical formation when topically applied to the skin by means of a cream has not been clearly established. The effectiveness of topical applications has been questioned due to vitamin C’s instability (it reacts with water and degrades). Some forms are said to have better stability in water systems. Synthetic analogues such as magnesium ascorbyl phosphate are among those considered more effective, as they tend to be more stable. When evaluating its ability to fight free-radical damage in light of its synergistic effect with vitamin e, vitamin C shines. As vitamin e reacts with a free radical, it, in turn, is damaged by the free radical it is fighting. Vitamin C comes in to repair the free-radical damage in vitamin e, allowing e to continue with its free-radical scavenging duties. Past research has indicated that high concentrations of topically applied vitamin C are photoprotective, and apparently the vitamin preparation used in these studies resisted soap and water, washing, or rubbing for three days. More current research has indicated that vitamin C does add protection against uVB damage when combined with uVB sunscreen chemicals. This would lead one to conclude that in combination with conventional sunscreen agents, vitamin C may allow for longer-lasting, broader sun protection. Again, the synergy between vitamins C and e can yield even better results, as apparently a combination of both provides very good protection from uVB damage. However, vitamin C appears to be significantly better than e at protecting against uVA damage. A further conclusion is that the combination of vitamins C, e, and sunscreen offers greater protection than the sum of the protection offered by any of the three ingredients acting alone. Vitamin C also acts as a collagen biosynthesis regulator. It is known to control intercellular colloidal substances such as collagen, and when formulated into the proper vehicles, can have a skin-lightening effect. Vitamin C is said to be able to help the body fortify against infectious conditions by strengthening the immune system. There is some evidence (although debated) that vitamin C can pass through the layers of the skin and promote healing in tissue damaged by burns or injury. It is found, therefore, in burn ointments and creams used for abrasions. Vitamin C is also popular in anti-aging products. Current studies indicate possible anti-inflammatory properties as well.
[CAS DataBase Reference]

50-81-7(CAS DataBase Reference)
[NIST Chemistry Reference]

L-Ascorbic acid(50-81-7)
[Storage Precautions]

Light sensitive
[EPA Substance Registry System]

50-81-7(EPA Substance)
Safety DataBack Directory
[Hazard Codes ]

Xn
[Risk Statements ]

R20/21/22:Harmful by inhalation, in contact with skin and if swallowed .
R36/37/38:Irritating to eyes, respiratory system and skin .
[Safety Statements ]

S24/25:Avoid contact with skin and eyes .
S36:Wear suitable protective clothing .
S26:In case of contact with eyes, rinse immediately with plenty of water and seek medical advice .
[WGK Germany ]

1
[RTECS ]

CI7650000
[TSCA ]

Yes
[HS Code ]

29362700
[Safety Profile]

Moderately toxic by ingestion and intravenous routes. Human systemic effects by intravenous route: blood, changes in tubules (including acute renal failure, acute tubular necrosis). An experimental teratogen. Other experimental reproductive effects. Mutation data reported. When heated to decomposition it emits acrid smoke and irritating fumes.
[Hazardous Substances Data]

50-81-7(Hazardous Substances Data)
[Toxicity]

LD50 oral in rat: 11900mg/kg
Raw materials And Preparation ProductsBack Directory
[Raw materials]

Sodium Methoxide-->Sodium hypochlorite-->Sorbitol-->2-Furoic acid-->Nickel sulfate-->D-Sorbitol-->Sodium erythorbate-->Gluconic acid-->2,5-Hexanedione-->GLOBULINS, CAT GAMMA-->SODIUM ERYTHORBATE-->Sodium ascorbate-->D-Glucose monohydrate-->Acetone-->Aluminium-nickel
[Preparation Products]

Gardenia blue pigment-->Magnesium ascorbyl phosphate-->BETANIN-->L-Carnitine-L-tartrate-->Ascorbyl Palmitate-->Hibiscetin-->Calcium diascorbate-->Sodium ascorbate-->L-ASCORBYL 6-STEARATE-->L-Threonic acid calcium salt-->2,3-Diketo-L-gulonic acid-->4-Phenylurazole-->Oxalic acid
Hazard InformationBack Directory
[General Description]

White to very pale yellow crystalline powder with a pleasant sharp acidic taste. Almost odorless.
[Reactivity Profile]

L-ASCORBIC ACID(50-81-7) is a lactone. Reacts as a relatively strong reducing agent and decolorizes many dyes. Forms stable metal salts. Incompatible with oxidizers, dyes, alkalis, iron and copper. Also incompatible with ferric salts and salts of heavy metals, particularly copper, zinc and manganese .
[Air & Water Reactions]

May be sensitive to prolonged exposure to air and light. Sensitive to moisture. Soluble in water. Aqueous solutions are oxidized by air in a reaction that is accelerated by alkalis, iron and copper. The rate depends on the pH and on oxygen concentration. Also subject to degradation under anaerobic conditions.
[Fire Hazard]

Flash point data for this chemical are not available; however, L-ASCORBIC ACID is probably combustible.
[Description]

Ascorbic acid (50-81-7), a water-soluble dietary supplement, is consumed by humans more than any other supplement. The name ascorbic means antiscurvy and denotes the ability of ascorbic to combat this disease. Vitamin C is the l-enantiomer of ascorbic acid. Ascorbic acid deficiency in humans results in the body’s inability to synthesize collagen, which is the most abundant protein in vertebrates.
[Chemical Properties]

Ascorbic acid occurs as a white to light-yellow-colored, nonhygroscopic, odorless, crystalline powder or colorless crystals with a sharp, acidic taste. It gradually darkens in color upon exposure to light.
[Chemical Properties]

White crystals (plates or needles). Soluble in water; slightly soluble in alcohol; insoluble in ether, chloroform, benzene, petroleum ether, oils and fats. Stable to air when dry. One international unit is equivalent to 0.05 milligram of l-ascorbic acid.
[Physical properties]

Appearance: white crystal or crystalline powder, and it is odorless and flavors sour. The color changes yellowish when exposed in the air for a long time. Its aqueous solution is acidic reaction. Solubility: vitamin C is soluble in water, slightly soluble in ethanol, and insoluble in chloroform or ether. Melting point: 190–192? °C.? It would decompose when it melts. Specific optical rotation: +20.5 to +21.5°. Ascorbic acid is two-base acid (the pKa is 4.1 and 11.8). It occurs mainly in the form of sodium salt and calcium salt, and its aqueous solution is strongly acidic reaction. Ascorbic acid is a strong reducing agent.
[Originator]

Ascorbic aci,Natur Product,France
[History]

Vitamin C is a general term for compounds having ascorbic acid activity, including ascorbic acid, dehydroascorbic acid, and its isomers.
The understanding of vitamin C has gone through a long and painful process. Although the relationship between scurvy and stored food is obvious, but the treatments of this disease have been misguided. By 1601, British armed Captain James Lancaster discovered the disease on the ship of the East India Company and regarded the scurvy as “rot,” which could be made tissue alkaline.
At the early stage of the nineteenth century, the understanding and treatment of scurvy had developed to a right approach. The exposition of scurvy etiology and metabolic theory took more than a century.
By the early stage of the twentieth century, inspired by the animal model of beriberi, researchers in the Christchurch Oslo University discovered one animal that could suffer scurvy accidentally and then established a valuable scurvy animal model. This experiment demonstrated that the extract isolated from lemon had antiscurvy activity. Until 1932, many research groups obtained the anti-scurvy crystal from different plants and identified the crystal as ascorbic acid vitamin C. Next year, the chemical structure of ascorbic acid was elucidated, and then its artificial synthesis was accomplished.
[Definition]

ChEBI: The L-enantiomer of ascorbic acid and conjugate acid of L-ascorbate.
[Indications]

Vitamin C (ascorbic acid) is essential for the maintenance of the ground substance that binds cells together and for the formation and maintenance of collagen.The exact biochemical role it plays in these functions is not known, but it may be related to its ability to act as an oxidation–reduction system.
[Production Methods]

Ascorbic acid is prepared synthetically or extracted from various vegetable sources in which it occurs naturally, such as rose hips, blackcurrants, the juice of citrus fruits, and the ripe fruit of Capsicum annuum L. A common synthetic procedure involves the hydrogenation of D-glucose to D-sorbitol, followed by oxidation using Acetobacter suboxydans to form L-sorbose. A carboxyl group is then added at C1 by air oxidation of the diacetone derivative of Lsorbose and the resulting diacetone-2-keto-L-gulonic acid is converted to L-ascorbic acid by heating with hydrochloric acid.
[Production Methods]

Ascorbic acid is produced synthetically using the Reichstein process, which has been the standard method of production since the 1930s. The process starts with fermentation followed by chemical synthesis. The first step involves reduction of D-glucose at high temperature into D-sorbitol. D-sorbitol undergoes bacterial fermentation, converting it into L-sorbose. L-sorbose is then reacted with acetone in the presence of concentrated sulfuric acid to produce diacetone-L-sorbose, which is then oxidized with chlorine and sodium hydroxide to produce di-acetone-ketogulonic acid (DAKS). DAKS is then esterified with an acid catalyst and organics to give a gulonic acid methylester. The latter is heated and reacted with alcohol to produce crude ascorbic acid, which is then recrystallized to increase its purity. Since the development of the Reichstein process more than 70 years ago, it has undergone many modifications. In the 1960s, a method developed in China referred to as the two-stage fermentation process used a second fermentation stage of L-sorbose to produce a different intermediate than DAKS called KGA (2-keto-L-gulonic acid), which was then converted into ascorbic acid. The two stage process relies less on hazardous chemicals and requires less energy to convert glucose to ascorbic acid.
[Manufacturing Process]

D-Glucose was reduced to the D-sorbitol with a hydrogen over Ni Raney, then it was turned into the L-sorbose with the acetobacter suboxydans and the hydroxyl groups of L-sorbose were protected with acetone treatment yielded the diaceton-L-sorbose. Subsequent treatment with NaOCl/Raney Ni produced di-O-isopropylidene-2-oxo-L-gulonic acid. Partial hydrolysis with aqueous HCl gave deprotected 2-oxo-L-gulonic acid, which yielded ascorbinic acid by heating with HCl.
[Brand name]

Ascorbin (Marion Merrell Dow).
[Therapeutic Function]

Vitamin
[Pharmaceutical Applications]

Ascorbic acid(50-81-7) is used as an antioxidant in aqueous pharmaceutical formulations at a concentration of 0.01–0.1% w/v. Ascorbic acid has been used to adjust the pH of solutions for injection, and as an adjunct for oral liquids. It is also widely used in foods as an antioxidant. Ascorbic acid has also proven useful as a stabilizing agent in mixed micelles containing tetrazepam.
[Biochem/physiol Actions]

L-ascorbic acid mainly exhibits antioxidant properties. It protects plants from oxidative stress and mammals from diseases associated with oxidative stress. L-ascorbic acid mainly protects from hydroxyl radicals, superoxide and singlet oxygen. In addition, it also reduces the membrane-linked antioxidant α-tocopherol (oxidised form). L-Ascorbic acid enhances endothelium-dependent vasodilation in various disorders, including diabetes, coronary artery disease, hypertension and chronic heart failure.
[Pharmacology]

Vitamin C is considered as a classical enzyme cofactor or antioxidant but also as a transition material in metal ion reaction. And all of these functions of vitamin C are related to the property of antioxidation.
[Clinical Use]

Vitamin C(50-81-7) is indicated for the treatment and prevention of known or suspect deficiency. Although scurvy occurs infrequently, it is seen in the elderly, infants, alcoholics, and drug users.Ascorbate can also be used to enhance absorption of dietary nonheme iron or iron supplements. Ascorbic acid (but not the sodium salt) was historically used to acidify the urine as a result of excretion of unchanged ascorbic acid, although this use has fallen into disfavor. Ascorbate also increases iron chelation by deferoxamine, explaining its use in the treatment of iron toxicity.
[Clinical Use]

Vitamin C is found in fresh fruit and vegetables. It is very water soluble, is readily destroyed by heat, especially in an alkaline medium, and is rapidly oxidized in air. Fruit and vegetables that have been stored in air, cut or bruised, washed, or cooked may have lost much of their vitamin C content. The deficiency disease associated with a lack of ascorbic acid is called scurvy. Early symptoms include malaise and follicular hyperkeratosis. Capillary fragility results in hemorrhages, particularly of the gums. Abnormal bone and tooth development can occur in growing children.The body’s requirement for vitamin C increases during periods of stress, such as pregnancy and lactation.
[Side effects]

Megavitamin intake of vitamin C may result in diarrhea due to intestinal irritation. Since ascorbic acid is partially metabolized and excreted as oxalate, renal oxalate stones may form in some patients.
[Toxicology]

L-Ascorbic acid, or vitamin C, is widely present in plants. The structures of ascorbic acid and dehydroascorbic acid are shown in Figure 10.5. Vitamin C is not only an important nutrient but is also used as an antioxidant in various foods. However, it is not soluble in fat and is unstable under basic conditions. Vitamin C reduces cadmium toxicity and excess doses prolong the retention time of an organic mercury compound in a biological system. Overdoses of vitamin C (106 g) induce perspiration, nervous tension, and lowered pulse rate. WHO recommends that daily intake be less than 0.15 mg/kg. Toxicity due to ascorbic acid has not been reported. Although repeated intravenous injections of 80 mg dehydroascorbic acid was reported to be diabetogenic in rats, oral consumption of 1.5 g/day of ascorbic acid for six weeks had no effect on glucose tolerance or glycosuria in 12 normal adult males and produced no change in blood glucose concentrations in 80 diabetics after five days. The same report noted that a 100-mg intravenous dose of dehydroascorbic acid given daily for prolonged periods produced no signs of diabetes. Ascorbic acid is readily oxidized to dehydroascorbic acid, which is reduced by glutathione in blood.
[Safety]

Ascorbic acid is an essential part of the human diet, with 40 mg being the recommended daily dose in the UK and 60 mg in the USA. However, these figures are controversial, with some advocating doses of 150 or 250mg daily. Megadoses of 10 g daily have also been suggested to prevent illness although such large doses are now generally considered to be potentially harmful.
The body can absorb about 500 mg of ascorbic acid daily with any excess immediately excreted by the kidneys. Large doses may cause diarrhea or other gastrointestinal disturbances. Damage to the teeth has also been reported. However, no adverse effects have been reported at the levels employed as an antioxidant in foods, beverages, and pharmaceuticals. The WHO has set an acceptable daily intake of ascorbic acid, potassium ascorbate, and sodium ascorbate, as antioxidants in food, at up to 15 mg/kg bodyweight in addition to that naturally present in food.
LD50 (mouse, IV): 0.52 g/kg
LD50 (mouse, oral): 3.37 g/kg
LD50 (rat, oral): 11.9 g/kg
[target]

p53 | DNA/RNA Synthesis | Mdm2
[Drug interactions]

Potentially hazardous interactions with other drugs
None known
[Metabolism]

Ascorbic acid is reversibly oxidised to dehydroascorbic acid; some is metabolised to ascorbate-2-sulfate, which is inactive, and oxalic acid which are excreted in the urine. Ascorbic acid in excess of the body's needs is also rapidly eliminated unchanged in the urine; this generally occurs with intakes exceeding 100 mg daily.
[storage]

In powder form, ascorbic acid is relatively stable in air. In the absence of oxygen and other oxidizing agents it is also heat stable. Ascorbic acid is unstable in solution, especially alkaline solution, readily undergoing oxidation on exposure to the air.The oxidation process is accelerated by light and heat and is catalyzed by traces of copper and iron. Ascorbic acid solutions exhibit maximum stability at about pH 5.4. Solutions may be sterilized by filtration.
The bulk material should be stored in a well-closed nonmetallic container, protected from light, in a cool, dry place.
[Purification Methods]

Crystallise it from MeOH/Et2O/pet ether [Herbert et al. J Chem Soc 1270 1933]. [Beilstein 18/5 V 26.]
[Toxicity evaluation]

Metabolism of ascorbic acid can lead to deposition of oxalate crystals in kidney tissue. Reduction of carcinogenic Cr(VI) by ascorbic acid generates ascorbate–Cr(III)–DNA cross-links that have been linked to mutagenicity and the formation of DNA lesions. Uranyl acetate–ascorbate has also been shown to nick plasmid DNA.
[Incompatibilities]

Incompatible with alkalis, heavy metal ions, especially copper and iron, oxidizing materials, methenamine, phenylephrine hydrochloride, pyrilamine maleate, salicylamide, sodium nitrite, sodium salicylate, theobromine salicylate, and picotamide. Additionally, ascorbic acid has been found to interfere with certain colorimetric assays by reducing the intensity of the color produced.
[Regulatory Status]

GRAS listed. Accepted for use as a food additive in Europe. Included in the FDA Inactive Ingredients Database (inhalations, injections, oral capsules, suspensions, tablets, topical preparations, and suppositories). Included in medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients.
Material Safety Data Sheet(MSDS)Back Directory
[msds information]

L-Threo-2,3,4,5,6-pentahydroxy-1-hexenoic acid-4-lactone(50-81-7).msds
Spectrum DetailBack Directory
[Spectrum Detail]

L(+)-Ascorbic acid(50-81-7)MS
L(+)-Ascorbic acid(50-81-7)1HNMR
L(+)-Ascorbic acid(50-81-7)13CNMR
L(+)-Ascorbic acid(50-81-7)IR1
L(+)-Ascorbic acid(50-81-7)IR2
L(+)-Ascorbic acid(50-81-7)Raman
L(+)-Ascorbic acid(50-81-7)ESR
Well-known Reagent Company Product InformationBack Directory
[Acros Organics]

L(+)-Ascorbic acid, 99%(50-81-7)
[Alfa Aesar]

L-(+)-Ascorbic acid, ACS, 99+%(50-81-7)
[Sigma Aldrich]

50-81-7(sigmaaldrich)
[TCI AMERICA]

L-Ascorbic Acid,>99.0%(T)(50-81-7)
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