7048-04-6

Basic information

• Product Name: L-Cysteine hydrochloride monohydrate
• Synonyms: L-2-AMINO-3-MERCAPTOPROPANOIC ACID HYDROCHLORIDE, MONOHYDRATE;L-2-AMINO-3-MERCAPTOPROPIONIC ACID MONOHYDROCHLORIDE;L-CYSTEINE HYDROCHLORIDE;L-CYSTEINE HYDROCHLORIDE 1-HYDRATE;L-CYSTEINE HYDROCHLORIDE HYDRATE;L-(+)-CYSTEINE HYDROCHLORIDE, MONOHYDRATE;L-CYSTEINE HYDROCHLORIDE MONOHYDRATE;L-CYSTEINE HYDROCHLORIDE SALT H2O
• CAS NO: 7048-04-6
• Molecular Formula: C₃H₈NO₂S*Cl*H₂O
• Molecular Weight: 175.63
• EINECS: 200-157-7
• Product Categories: Cysteine [Cys, C];alpha-Amino Acids;Amino Acids;Antioxidant;Biochemistry;Nutritional Supplements;L-Amino Acids;BioUltra;Cysteine/CystineIon Channels;Excitatory Amino Acids;Ionotropic Glutamate Receptor ModulatorsNeurotransmitters;Ligand-Gated Ion Channels;NMDA Agonists;Amino AcidsBiochemicals and Reagents;Core Bioreagents;Research Essentials;Amino AcidsPeptide Synthesis;Amino Acid Derivatives;Cysteine/Cystine;Amino AcidsPharmacopoeia (USP);Pharmacopoeia A-ZPharmacopoeia (USP);Pharmacopoeial Amino Acids;Amino Acids;Biochemicals and Reagents;amino;Amino acid
• Mol File: 7048-04-6.mol

Chemical Properties

• Melting Point: 175°C
• Boiling Point: 293.9 °C at 760 mmHg
• Flash Point: 131.5 °C
• Appearance: White/Solid
• Density: 1.54 g/cm3
• Vapor Pressure: 0.000411mmHg at 25°C
• Refractive Index: 6 ° (C=8, 1mol/L HCl)
• Storage Temp.: Store at RT.
• Solubility: H2O: 1 M at 20 °C, clear, colorless
• Water Solubility: Soluble in cold water.
• Sensitive: Hygroscopic
• Stability: Stable. Incompatible with strong oxidizing agents, most common metals, hydrogen chloride.
• Merck: 14,2781
• BRN: 5158059
• CAS DataBase Reference: L-Cysteine hydrochloride monohydrate(CAS DataBase Reference)
• NIST Chemistry Reference: L-Cysteine hydrochloride monohydrate(7048-04-6)
• EPA Substance Registry System: L-Cysteine hydrochloride monohydrate(7048-04-6)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-36
• WGK Germany: 3
• RTECS: HA2285000
• F: 3-10-23
• TSCA: Yes
• Hazardous Substances Data: 7048-04-6(Hazardous Substances Data)

Usage

Chemical Description

L-cysteine hydrochloride monohydrate is an amino acid that contains a thiol group and is commonly used in protein synthesis.

Uses

Used in Food Industry:
L-Cysteine hydrochloride monohydrate is used as a precursor for the production of flavors, particularly meat flavor obtained by reacting with sugars. It is also used as a processing aid for baking and as an additive in cigarettes.
Used in Pharmaceutical Industry:
L-Cysteine hydrochloride monohydrate plays an important role as a key raw material for the manufacture of N-acetyl-L-cysteine, S-carboxymethyl-L-cysteine, and L-cysteine base. It is involved in the treatment of liver disease as an antioxidant and antidote.
Used in Personal Care Products:
L-Cysteine hydrochloride monohydrate is used as a precursor in the production of personal care products.
Used in Animal Feed Industry:
Being an essential amino acid, it is used as an additive in animal feed, especially for sheep, which is responsible for the growth of wool.
Used in Research and Development:
L-Cysteine hydrochloride monohydrate has been used as a component of yeast dropout media for culturing yeasts and as a component of differential reinforced clostridial broth (DRCM) for the isolation of clostridia. It has also been used in protocols to isolate dorsal root ganglion neurons (DRG) and in research to test its effect as an inhibitor of enzymatic browning of apples.
Note: The product is supplied for R&D use only and not for drug, household, or other uses.

General descriptio

L-cysteine ??hydrochloride monohydrate (LCHCMH) is a water-soluble salt of the non-essential amino acid L-cysteine. It is widely used in the pharmaceutical industry. The thermodynamic characteristics of LCHCMH in aqueous solution have been reported. [1] It can be crystallized in an orthogonal system with the P212121 space group. Its nonlinear optical (NLO) characteristics have been studied in single crystals grown by unidirectional Sankaranarayanan-Ramasamy (SR) technology.

Biochem/physiol Actions

NMDA glutamatergic receptor antagonist.

InChI:InChI=1/C3H7NO2S.ClH.H2O/c4-2(1-7)3(5)6;;/h2,7H,1,4H2,(H,5,6);1H;1H2/t2-;;/m0../s1

Synthetic route

dimethyltin oxide (2273-45-2) + L-cysteine hydrochloride monohydrate (7048-04-6) → chlorodimethyltin(IV) L-cysteine monohydrate

Conditions	Yield
In hydrogenchloride	99%

hexammine cobalt(III) chloride + barium hydroxide octahydrate + L-cysteine hydrochloride monohydrate (7048-04-6) → 1.5Ba(2+)*Co(C3H5NO2S)3(3-)*5H2O = Ba1.5[Co(C3H5NO2S)3]*5H2O

Conditions	Yield
In water (argon); 70°C, 2 h; elem. anal.;	96%

L-cysteine hydrochloride monohydrate (7048-04-6) + 2,4-Dihydroxybenzaldehyde (95-01-2) → (4R)-2-(2,4-dihydroxyphenyl)thiazolidine-4-carboxylic acid (1367664-23-0)

Conditions	Yield
With sodium acetate In ethanol; water at 20℃; for 14h;	95.8%

Divinyl sulfone (77-77-0) + L-cysteine hydrochloride monohydrate (7048-04-6) → C7H13NO4S2*ClH

Conditions	Yield
In methanol at 50℃; for 100h;	95%

L-cysteine hydrochloride monohydrate (7048-04-6) + potassium dicyanoaurate → [(L-cysteinato)gold(I)]

Conditions	Yield
In water mixing of the components in double-distd. water and standing at 4°C overnight; sepn. of the ppt., washing with EtOH and dry Et2O and drying (P2O5, vac.); elem. anal.;	88.4%

acetic anhydride (108-24-7) + L-cysteine hydrochloride monohydrate (7048-04-6) → N-acetylcystein (616-91-1)

Conditions	Yield
With sodium acetate In tetrahydrofuran; water at 10 - 60℃; for 37h; pH=4 - 5; Inert atmosphere;	85%

hexammine cobalt(III) chloride + lithium hydroxide monohydrate (1310-66-3) + L-cysteine hydrochloride monohydrate (7048-04-6) → trilithium fac-Δ-tris(R-cysteinato-N,S)cobaltate(III) heptahydrate

Conditions	Yield
In water 70°C, 2 h, addn. of EtOH, stirring (20°C, 12 h); elem. anal.;	82%

hexammine cobalt(III) chloride + L-cysteine hydrochloride monohydrate (7048-04-6) + sodium hydroxide (1310-73-2) → trisodium fac-Δ-tris(R-cysteinato-N,S)cobaltate(III) * 11 H2O

Conditions	Yield
In water 70°C, 2 h, addn. of EtOH, stirring (20°C, 12 h); elem. anal.;	80%

hexammine cobalt(III) chloride + L-cysteine hydrochloride monohydrate (7048-04-6) + potassium hydroxide → tripotassium fac-Δ-tris(R-cysteinato-N,S)cobaltate(III) * 6.5 H2O

Conditions	Yield
In water 70°C, 2 h, addn. of EtOH, stirring (20°C, 12 h); elem. anal.;	80%

hexammine cobalt(III) chloride + rubidium hydroxide + L-cysteine hydrochloride monohydrate (7048-04-6) → trirubidium fac-Δ-tris(R-cysteinato-N,S)cobaltate(III) nonahydrate

Conditions	Yield
In water 70°C, 2 h, addn. of EtOH, stirring (20°C, 12 h); elem. anal.;	80%

cesium hydroxide + hexammine cobalt(III) chloride + L-cysteine hydrochloride monohydrate (7048-04-6) → tricesium fac-Δ-tris(R-cysteinato-N,S)cobaltate(III) octahydrate

Conditions	Yield
In water 70°C, 2 h, addn. of EtOH, stirring (20°C, 12 h); elem. anal.;	80%

2-fluorobenzyl chloride (345-35-7) + L-cysteine hydrochloride monohydrate (7048-04-6) → (2R)-2-amino-3-(2-fluorobenzylthio)propanol + (2R)-2-amino-3-(2-fluorobenzylthio)propionic acid

Conditions	Yield
With hydrogenchloride In methanol; water	A n/a B 74.8%

2,4-dihydroxybenzonitrile (64419-24-5) + L-cysteine hydrochloride monohydrate (7048-04-6) → C10H9NO4S (57980-69-5)

Conditions	Yield
With sodium hydrogencarbonate In methanol	69%

ammonium tetrathiotungstate (13862-78-7) + potassium chloride + L-cysteine hydrochloride monohydrate (7048-04-6) → potassium (di-μ-sulfido)bis{(L-cysteinato)oxotungstate(V)} pentahydrate

Conditions

Yield

With HCl; KOH In water dropwise addn. of concd. HCl to aq. W compd. soln. with stirring; addn. of L-cysteine; stirring, several min; adjusting to pH 7 (KOH); heating at 50-60°C, 30 min; addn. of KCl; cooling to room temp.; storage in refrigerator overnight; crystn.; filtration; washing (methanol); recrystn. by dissoln. in hot water; filtration; addn. of KCl; allowing to stand overnight in a refrigerato; crystn.; elem. anal.;

50%

water (7732-18-5) + L-cysteine hydrochloride monohydrate (7048-04-6) + 2-chloro-3-(1H-imidazol-4-yl)propanoic acid (6630-42-8, 17561-26-1, 17561-27-2, 36392-60-6) → 2-amino-3-(1-carboxy-2-(1H-imidazol-4-yl)ethylthio)propanoic acid

Conditions	Yield
With sodium hydroxide In ethanol for 72h; Inert atmosphere;	50%

ammonium tetrathiotungstate (13862-78-7) + L-cysteine hydrochloride monohydrate (7048-04-6) → ammonium (di-μ-sulfido)bis{(L-cysteinato)oxotungstate(V)} trihydrate

Conditions	Yield
With NH4Cl; HCl; NH3 In water dropwise addn. of HCl to aq. W compd. soln. with stirring; addn. of cysteine; stirring, several min; adjusting pH to 7 (NH3); heating, 50-60°C, 30 min; addn. of NH4Cl; cooling to room temp.; storage in refrigerator overnight; crystn.; filtration; washing (methanol); recrystn.; elem. anal.;	46%

4-nitrobenzyl chloride (100-14-1) + L-cysteine hydrochloride monohydrate (7048-04-6) → (2R)-2-amino-3-(4-nitrobenzylthio)propanol + L-2-amino-3-(4-nitrobenzylthio)propionic acid (90899-86-8)

Conditions	Yield
With hydrogenchloride; sodium hydroxide	A n/a B 45.9%

ammonium tetrathiotungstate (13862-78-7) + L-cysteine hydrochloride monohydrate (7048-04-6) → sodium (di-μ-sulfido)bis{(L-cysteinato)oxotungstate(V)} trihydrate

Conditions	Yield
With NaCl; HCl In water dropwise addn. of HCl to aq. W compd. soln. with stirring; addn. of cysteine; stirring, several min; adjusting pH to 7 (NaOH); heating, 50-60°C, 30 min; addn. of NaCl; cooling to room temp.; storage in refrigerator overnight; crystn.; filtration; washing (methanol); recrystn.; elem. anal.;	40%

sodium molybdate dihydrate (7631-95-0) + water (7732-18-5) + L-cysteine hydrochloride monohydrate (7048-04-6) → 3Na(1+)*Mo154O462H14(H2O)48(H(O2CC(NH3)HCH2S)2)11(3-)*250H2O=Na3[Mo154O462H14(H2O)48(H(O2CC(NH3)HCH2S)2)11]*250H2O

Conditions	Yield
In water stirred at room temp. for 5 min, heated at 55°C for 2 h (stirring), kept for 2 h at 20°C; filtered, standed for 2 d at 15-20°C, crysts. filtered, washed (cold water), dried (room temp.); elem. anal., TGA;	37%

ammonium tetrathiotungstate (13862-78-7) + L-cysteine hydrochloride monohydrate (7048-04-6) → potassium di-μ-sulfido-bis{(cysteinato)oxotungstate(V)}

Conditions	Yield
With HCl; KOH; KCl In water concd. HCl is added to aq. soln. of W-compd., cysteine compd. is added, pH is adjusted to 7 (KOH), soln. is heated for 20 min, cooled to room temp. and filtered, KCl is added to the filtrate; soln. is kept in refrigerator overnight, crystals are filtered off, washed with MeOH and Et2O and recrystd. from hot H2O, elem. anal.;	35%

sodium tungstate (VI) dihydrate (10213-10-2) + sodiumsulfide nonahydrate + L-cysteine hydrochloride monohydrate (7048-04-6) → potassium (di-μ-sulfido)bis{(L-cysteinato)oxotungstate(V)} pentahydrate

Conditions	Yield
With HCl; KOH In water slow addn. of concd. HCl to aq. soln. of Na2WO4 and Na2S; addn. of L-cysteine; adjusting to pH 7 (KOH); heating at 50-70°C, 20 min; filtration; addn. of KCl; filtration; washing (methanol); recrystn. by dissoln. in hot water; filtration; addn. of KCl; allowing to stand overnight in a refrigerato; crystn.; elem. anal.;	35%

sodium hydrogen selenide + ammonium heptamolybdate tetrahydrate + cesium chloride + L-cysteine hydrochloride monohydrate (7048-04-6) → 2Cs(1+)*{Mo2O2Se2(O2CCH(NH2)CH2S)2}(2-)*4H2O=Cs2{Mo2O2Se2(O2CCH(NH2)CH2S)2}*4H2O

Conditions	Yield
In water slow addn. of freshly prepd. NaHSe in H2O to aq. soln. of (NH4)6(Mo7O24)*6H2O; stirring for 24 h; filtering, addn. of HO2CCH(NH2)CH2SH in H2O (pH adjusted to 6 with NaOH); standing for 24 h at room temp., refiltering;; pptn. on addn. of CsCl in H2O; recrystn. from hot H2O; elem. anal.;;	33.7%

tetrabutylammonium [(99g)Tc]tetrachlorooxotechnetate(V) + L-cysteine hydrochloride monohydrate (7048-04-6) + barium(II) chloride → Ba(2+)*2(99)TcO(NH2CH(CH2S)CO2)2(1-)=Ba[(99)TcO(NH2CH(CH2S)CO2)2]2

Conditions	Yield
With AcONH4 In methanol; water slow addn. of aq. cysteine to Tc-complex (in MeOH), pH-adjustment to 7.4(AcONH4), chromy. (celulose, MeOH; then Sephadex LH-20), concn., BaCl2 addn. (pptn.); recrystn. (50% aq. MeOH); elem. anal.;	33%

L-cysteine hydrochloride monohydrate (7048-04-6) + 2-Bromoacetyl bromide (598-21-0) → (R)-5-oxothiomorpholine-3-carboxylic acid (62305-89-9)

Conditions	Yield
With sodium carbonate In water for 12h; Ambient temperature;	15%

L-cysteine hydrochloride monohydrate (7048-04-6) + formamidine disulfide dihydrochloride (1 mol) → S-guanylsulfanyl-L-cysteine (89838-59-5)

Downstream Products

• 62305-89-9 (R)-5-oxothiomorpholine-3-carboxylic acid 
• 56-89-3 L-cystine 
• 17356-08-0 thiourea 
• 250587-00-9 (3R)-8-(4-isopropylphenoxy)-1-thia-4-azaspiro[4.5]decan-3-carboxylic acid 
• 204695-04-5 S-[(α,α-Dimethyl-4-isopropyl)benzyl]-L-cysteine hydrochloride 
• 124529-02-8 N-isobutyryl-L-cysteine 
• 57980-69-5 C₁₀H₉NO₄S 
• 1367664-23-0 (4R)-2-(2,4-dihydroxyphenyl)thiazolidine-4-carboxylic acid 
• 921-01-7 rac-cysteine 
• 616-91-1 N-acetylcystein 
• 14226-97-2 L-5-oxo-thiomorpholine-3-carboxylic acid 
• 90899-86-8 L-2-amino-3-(4-nitrobenzylthio)propionic acid 

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