L-Cisteine·hydrochloride
Cysteine Hydrochloride
CAS: 52-89-1
Molecular Formula: C3H8ClNO2S
L-Cisteine·hydrochloride - Names and Identifiers
L-Cisteine·hydrochloride - Physico-chemical Properties
| Molecular Formula | C3H8ClNO2S |
| Molar Mass | 157.62 |
| Melting Point | 180°C |
| Specific Rotation(α) | 5.5 º (c=8, 6 N HCL) |
| Water Solubility | SOLUBLE |
| Solubility | H2O: 1M at20°C, clear, colorless |
| Appearance | Solid |
| Color | White to light brown |
| Merck | 14,2781 |
| BRN | 3560277 |
| Storage Condition | Inert atmosphere,Room Temperature |
| Stability | Stable, but light, moisture and air sensitive. Incompatible with strong oxidizing agents, some metals. |
| Sensitive | Hygroscopic |
| Physical and Chemical Properties | White Crystal or crystalline powder, odor, acid, soluble in water, ammonia, acetic acid, ethanol-soluble, acetone, ethyl acetate, benzene, carbon disulfide, carbon tetrachloride. Acid stability, and in neutral or slightly alkaline solution is easy to be air oxidation into cystine, trace iron and heavy metal ions can promote oxidation. Its hydrochloride is more stable, so it is generally made into hydrochloride. L-cysteine is a sulfur-containing non-essential amino acid. In the living body, the hydroxyl oxygen atom of serine is replaced by the sulfur atom of methionine and synthesized via the thioether. L-cysteine can generate glutathione, involved in the reduction process of cells and phospholipid metabolism in the liver, can protect liver cells from damage, and can stimulate hematopoietic function, increase white blood cells, promotes the repair of skin lesions. Its mp is 175 ℃, decomposition temperature is 175 ℃, isoelectric point is 5.07, [α]25D-16.5 (H2O), [α]25D 6.5 (5mol/L, HCl). |
L-Cisteine·hydrochloride - Risk and Safety
| Hazard Symbols | Xi - Irritant |
| Risk Codes | 36/37/38 - Irritating to eyes, respiratory system and skin. |
| Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36 - Wear suitable protective clothing. |
| WGK Germany | 2 |
| RTECS | HA2275000 |
| FLUKA BRAND F CODES | 3-10-23 |
| TSCA | Yes |
| HS Code | 29309013 |
| Toxicity | LD50 intraperitoneal in mouse: 1250mg/kg |
L-Cisteine·hydrochloride - Application
1. medicine: cysteine hydrochloride is soluble in water and can be quickly absorbed by human body when made into injection or tablet. It is the main raw material for the production of carboxymethyl cysteine and acetylcysteine; levohydrocysteine hydrochloride monohydrate is soluble in water and can be quickly absorbed by the human body after being made into injections or tablets, so it can be directly pharmaceutically, clinically It can treat leukopenia, leukopenia caused by the application of anti-cancer drugs and radiopharmaceuticals, and heavy metal poisoning antidotes. In addition, it is also used, it can prevent liver necrosis, treat bronchitis and reduce phlegm, detoxify propylene and aromatic poisoning, and prevent radiation damage.
2. Food: Cysteine hydrochloride is used as a fast-growing promoter of bread in food, which can change the flavor of bread and food.
3. Promote fermentation and prevent oxidation: Cysteine hydrochloride can be used as a nutritional supplement, antioxidant, and color protector for natural juice to prevent vitamin C oxidation and color change. Cysteine hydrochloride has a detoxification effect on propylene and aromatic poisoning, and has the effect of preventing radiation damage.
4. Cosmetics: Cysteine hydrochloride can be used in cosmetics for perm, sunscreen, hair growth perfume and hair conditioner.
5. Others: Cysteine hydrochloride is the main raw material for the production of carboxymethyl cysteine and acetylcysteine
Last Update：2024-04-09 20:48:19
L-Cisteine·hydrochloride - Reference Information
| NIST chemical information | Information provided by: webbook.nist.gov (external link) |
| EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
| properties | l cysteine hydrochloride is colorless to white crystal or crystalline powder, with slight special smell and sour taste, melting point 175 ℃ (decomposition). Soluble in water, the aqueous solution is acidic, the pH value of 1% solution is about 1.7, and the pH value of 0.1% solution is about 2.4. It can also be soluble in alcohol, ammonia and acetic acid, but insoluble in ether, acetone, benzene, etc. It has the characteristics of reducing, anti-oxidation and preventing non-enzymatic browning. |
| preparation method | hydrolyze hair with hydrochloric acid, distill under reduced pressure, distill hydrochloric acid, then decolorize, filter, take filtrate and add ammonia to neutralize L-cystine crude crystal, then dissolve and neutralize it with ammonia water, recrystallize, then dissolve it with hydrochloric acid and electrolytically reduce, concentrate, cool, crystallize and dry. |
| use | is used to treat radioactive drug poisoning, heavy metal poisoning, toxic hepatitis, serum sickness, etc., and can prevent liver necrosis. Used as a component of cosmetics perm, sunscreen, hair growth perfume, hair nourishing essence; can be used as a food additive to prevent vitamin C oxidation and discoloration; used in bread to promote gluten protein formation and fermentation, mold, etc. Widely used in cosmetics, medicine, food and other industries used in medicine, food and other used in biochemical research, used as a reducing agent for the determination of hemolysin, used as an antidote in medicine. Pharmaceuticals, food. It is used to treat radioactive drug poisoning, heavy metal poisoning, toxic hepatitis, serum sickness, etc., and can prevent liver necrosis. Used as a component of cosmetics perm, sunscreen, hair growth perfume, hair nourishing essence; can be used as a food additive to prevent vitamin C oxidation and discoloration; used in bread to promote gluten protein formation and fermentation, mold, etc. NMDA glutamatergic receptor agonists are also AMPA glutamatergic receptor agonists at high concentrations. |
| production method | L-cystine is used as raw material, reduced with stannous chloride in hydrochloric acid medium, and then crystallized and refined. method 1. hydrolysis-electrolysis method uses pig hair and hair as raw materials to separate cystine from cystine by hydrolysis and adjusting the isoelectric point of cystine, and then electrolytically reduce cystine to obtain cysteine. Hydrolysis separates cystine pig hair and hair [HCl, 117 ℃, 7h]→ [acid hydrolysis] hydrolysate [NaOH, pH4.8]→ [neutralization] L-cystine (crude) electrolytic reduction in two separate pools, one pool is filled with 1mol/L HCl inserted into an ink rod, connected to the positive electrode of the power supply, this pool is the anode, and the other pool is filled with cystine hydrochloric acid solution (cystine: concentrated HCl: water = 1:1:4), insert the lead plate, connect the negative pole of the power supply, this pool is the cathode. Add salt bridge connection between the two pools. Turn on the power supply to adjust the current 5A and carry out electrolysis. Electrolysis is completed for about 6-7h. Take the electrolyte and add pyridine a little drop, no turbidity indicates that the electrolysis is completed. L-cystine [HCl]→ [electrolytic reduction] L-cysteine hydrochloride [decolorization, concentration, crystallization] → L-cysteine hydrochloride crystallization decolorization, concentration, crystallization electrolysis is completed, cut off the power supply, add 10g/L(1%) activated carbon according to the feeding amount, heat to 70 ℃, and keep the temperature for half an hour. Filter to get the filtrate. And concentrate it under reduced pressure until there is crystallization, stir to completely precipitate the crystallization, filter to take the crystallization, wash with 95% ethanol, and dry in vacuum below 60 ℃ to obtain L-cysteine hydrochloride without crystal water. Methods 2. enzymatic hydrolysis of DL-2-aminodihydrothiazoline -4-carboxylic acid (DL-ATC) |
Last Update：2024-04-10 20:29:42
