51-79-6 Usage
Description
Urethane, also known as Ethyl Carbamate, is a poisonous, flammable organic compound that occurs as odorless colorless crystals or white powder. It is soluble in water, alcohol, ether, glycerol, and chloroform, and slightly soluble in olive oil. Urethane sublimates readily at 217°F and 54 mm Hg and has a cooling saline taste. It is used as an intermediate in the synthesis of various chemical products, including pharmaceuticals, and as a solubilizer and co-solvent for pesticides and fumigants.
Uses
Used in Chemical Synthesis:
Urethane is used as a chemical intermediate in the preparation of amino resins. It reacts with formaldehyde to produce hydroxymethyl derivatives that act as cross-linking agents in permanent-press textile treatments, providing wash-and-wear properties to fabrics.
Used in Solvent and Co-solvent Applications:
Urethane serves as a solubilizer and co-solvent in the manufacture of pesticides, fumigants, and cosmetics, due to its solubility in various substances.
Used in Pharmaceutical Industry:
Urethane is used as an intermediate in the manufacture of pharmaceuticals and in biochemical research. However, it was formerly used as an active ingredient in drugs prescribed for the treatment of neoplastic diseases, as a sclerosing solution for varicose veins, as a hypnotic, and as a topical bactericide. Due to its toxic and carcinogenic properties, it has been withdrawn from pharmaceutical use by the U.S. FDA.
Used in Veterinary Medicine:
Urethane is used as an anesthetic in veterinary medicine, particularly in laboratory procedures.
Used in Fermentation Processes:
Urethane is produced naturally during many fermentation processes, such as in wine, stone-fruit brandies, bread, and other fermented products.
Used in Organic Synthesis:
Urethane is utilized as an intermediate in organic synthesis, contributing to the preparation and modification of amino resins.
Occurrence:
Urethane (ethyl carbamate) occurs as a natural byproduct in fermented products such as wine, liquors, yogurt, beer, bread, olives, cheeses, and soy sauces. Although it has a known cancer etiology in experimental animals, no such relationship has yet been proven in humans. Alcohol may act by blocking the metabolism of urethane, potentially exerting a protective effect in humans consuming alcoholic beverages.
World Health Organization (WHO)
Urethane was formerly used as an antineoplastic agent in the
treatment of chronic myeloid leukaemia. It is also a mild hypnotic which has been
used as an anaesthetic for veterinary practice. It has been reported to have both a
carcinogenic and mutagenic potential. Although urethane continues to be used as
an industrial solvent, WHO has no information to suggest that it remains
commercially available in pharmaceutical preparations.
Air & Water Reactions
Water soluble. Aqueous solutions are neutral to litmus .
Reactivity Profile
Urethane is incompatible with alkalis, acids, chloral hydrate, camphor, menthol and thymol. Also incompatible with antipyrine and salol. May react with strong oxidizing agents. Liquefies with benzoic acid, resorcinol and salicylic acid. Reacts with phosphorus pentachloride to form an explosive product .
Hazard
Toxic by ingestion.
Safety Profile
Confirmed carcinogen
with experimental carcinogenic,
neoplastigenic, and tumorigenic data. A
transplacental carcinogen. Moderately toxic
by ingestion, intraperitoneal, subcutaneous,
intramuscular, parenteral, and intravenous
routes. An experimental teratogen.
Experimental reproductive effects. Human
mutation data reported. Causes depression
of bone marrow and occasionally focal
degeneration in the brain. Can also produce
central nervous system depression, nausea
and vomiting. Has been found in over 1000
beverages sold in the United States. The
most heavily contaminated liquors are
bourbons, sherries, and fruit brandies (some had 1000 to 12,000 ppb urethane). Many
whiskeys, table and dessert wines, brandies,
and liqueurs contain potentially hazardous
amounts of urethane. The allowable limit for
urethane in alcoholic beverages is 125 ppb.
It is formed as a side product during
processing.Hot aqueous acids or alkalies decompose
urethane to ethanol, carbon dioxide, and
ammonia. Reacts with phosphorus
pentachloride to form an explosive product.
When heated it emits toxic fumes of NOx.
Used as an intermedate in the manufacture
of pharmaceuticals, pesticides, and
fungicides. See also CARBAMATES.
Potential Exposure
Urethane is used as a chemical intermediate
in manufacture of pharmaceuticals; pesticides, and
fungicides; in the preparation of amino resins. It may be
reacted with formaldehyde to give cross-linking agents
which impart wash-and-wear properties to fabrics. It has
also been used as a solubilizer and cosolvent in the manufacture
of pesticides, fumigants, and cosmetics. It was formerly
used in the treatment of leukemia. It occurs when
diethylpyrocarbonate, a preservative used in wines, fruit
juices, and soft drinks, is added to aqueous solutions.
Carcinogenicity
Urethane is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals.
Environmental Fate
Urethane may be released to the environment in various waste
streams. If released to the atmosphere, urethane is expected to
exist solely as a vapor in the ambient atmosphere. Vapor-phase
urethane is degraded in the atmosphere by reaction with
photochemically produced hydroxyl radicals with an estimated
half-life of 2.2 days. If released to soil, urethane has very high mobility. Volatilization from moist soil surfaces does not
occur. Biodegradation of urethane in soil may be important. If
released into water, urethane is not adsorbed to suspended
solids and sediment in the water column. Volatilization from
water surfaces does not occur. The potential for bioconcentration
in aquatic organisms is low based on an estimated
bioconcentration factor (BCF) of 0.45. Urethane is
resistant to hydrolysis under environmental conditions;
hydrolysis half-lives of 3300 and 330 years at pH 7 and 8,
respectively, were estimated for urethane. Urethane was judged
easy to biodegrade in river die-away tests. Other biodegradation
studies using activated sludge indicate urethane may
biodegrade slowly.
Purification Methods
Urethane is best purified by fractional distillation, but it can be 20 25 1.4144. sublimed at ~103o/~50mm. It has also been recrystallised from *benzene. Its solubilitiy at room temperature is 2g/mL in H2O, 1.25g/mL in EtOH, 1.1g/mL in CHCl3, 0.67g/mL in Et2O and 0.03g/mL in olive oil. It is a suspected human carcinogen.[Beilstein 3 H 22, 3 IV 40.]
Toxicity evaluation
Urethane is activated in the liver into a carcinogenic metabolite.
The activation of urethane by cytochrome P450 involves two
sequential reactions. First, urethane is dehydrogenated to vinyl
carbamate followed by epoxidation to form vinyl carbamate
epoxide. The former is believed to be the ultimate carcinogenic
metabolite of urethane.
Incompatibilities
Dust may form explosive mixture with
air. Incompatible with oxidizers (chlorates, nitrates, peroxides,
permanganates, perchlorates, chlorine, bromine, fluorine,
etc.); contact may cause fires or explosions. Keep
away from alkaline materials, strong bases, strong acids,
oxoacids, epoxides, gallium, perchlorate.
Waste Disposal
Consult with environmental
regulatory agencies for guidance on acceptable disposal
practices. Generators of waste containing this contaminant
(≥100 kg/mo) must conform to EPA regulations
governing storage, transportation, treatment, and waste
disposal. Controlled incineration (incinerator equipped
with a scrubber or thermal unit to reduce nitrogen oxides
emissions).
Check Digit Verification of cas no
The CAS Registry Mumber 51-79-6 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 5 and 1 respectively; the second part has 2 digits, 7 and 9 respectively.
Calculate Digit Verification of CAS Registry Number 51-79:
(4*5)+(3*1)+(2*7)+(1*9)=46
46 % 10 = 6
So 51-79-6 is a valid CAS Registry Number.
InChI:InChI=1/C3H7NO2/c1-2-6-3(4)5/h2H2,1H3,(H2,4,5)
51-79-6Relevant articles and documents
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Fuchigami,Nonaka
, p. 1087,1088,1089 (1977)
-
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Steyermark
, p. 3570 (1963)
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CARBONYLATION OF 2 AND 2; A NEW SELECTIVE METHOD FOR PREPARATION OF
Monica, G. La,Monti, C.,Pizzotti, M.,Cenini, S.
, p. 241 - 244 (1983)
Carbonylation of 2 (COD=1,5-cyclooctadiene) in ethanol gave the rhodium cluster selectively in high yield; when non polar solvents were used, the known 2 and 2 were obtained.Reaction of carbon monoxide with the isocyanato-bridged derivative 2 in ethanol also gave .In both cases the carbonylation reaction also gave NH2COOEt.Carbonylation of the iridium dichloride dimer 2 in the presence of sodium citrate gave .
Discovery of a dual tubulin polymerization and cell division cycle 20 homologue inhibitor via structural modification on apcin
Huang, Pan,Le, Xiangyang,Huang, Fei,Yang, Jie,Yang, Haofeng,Ma, Junlong,Hu, Gaoyun,Li, Qianbin,Chen, Zhuo
, p. 4685 - 4700 (2020/06/08)
Apcin is one of the few compounds that have been previously reported as a Cdc20 specific inhibitor, although Cdc20 is a very promising drug target. We reported here the design, synthesis, and biological evaluations of 2,2,2-trichloro-1-aryl carbamate derivatives as Cdc20 inhibitors. Among these derivatives, compound 9f was much more efficient than the positive compound apcin in inhibiting cancer cell growth, but it had approximately the same binding affinity with apcin in SPR assays. It is possible that another mechanism of action might exist. Further evidence demonstrated that compound 9f also inhibited tubulin polymerization, disorganized the microtubule network, and blocked the cell cycle at the M phase with changes in the expression of cyclins. Thus, it induced apoptosis through the activation of caspase-3 and PARP. In addition, compound 9f inhibited cell migration and invasion in a concentration-dependent manner. These results provide guidance for developing the current series as potential new anticancer therapeutics.
Preparation method of (5-toluenesulfonyl-5H-pyrrolo[2,3-b]pyrazine-2-yl)ethyl carbamate
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Paragraph 0012-0014, (2019/10/01)
The invention discloses a preparation method of (5-toluenesulfonyl-5H-pyrrolo[2,3-b]pyrazine-2-yl)ethyl carbamate, and belongs to the field of the chemical industry. The preparation method comprises the following steps: (1) preparation of N-ethyl carbamate: adopting ethanol as a solvent, performing a reaction on isocyanate and ethyl bromide zinc acetate at a molar ratio of 1:(2-3) at 35-40 DEG C for 6-8 hours under the protection of nitrogen, performing quenching with a saturated ammonium chloride solution after completion of the reaction, extracting the organic phase by using diethyl ether, and performing separation through column chromatography so as to obtain the target product; and (2) preparation of a mixed acid: adding fuming sulphuric acid with a mass concentration of 20-40% to sulfonic acid with a mass concentration of 50-70% so as to prepare the mixed acid. Through the preparation method, the preparation steps are reduced, the production cost is reduced, the production time issaved, the preparation efficiency is improved, and the preparation method is suitable for popularization and application.