Cysteine

C3H7NO2SCAS 52-90-4121.15 g/mol

Open in Covalent MOL file
NH2HSOOH
Carboxylic acidPrimary amineThiol

Properties

Molecular formula
C3H7NO2S
Molar mass
121.15 g/mol
Exact mass
121.0197 Da
Density
1.6666 g/mL (at 45 °C)
Melting point
240 °C (decomposes)
pKa
1.71, 8.33, 10.78
Water solubility
freely soluble
logP
-0.67Crippen estimate
Polar surface area
63.3 Ų
H-bond donors / acceptors
3 / 3
Rotatable bonds
2
Stereocentres
Rin SMILES atom order

Hazards

Warning
Irritant (GHS07)

Aggregated from 529 ECHA notifications, via PubChem; a share says how many notifiers assign that statement.

Precautionary statements

P261, P264, P264+P265, P270, P271, P280, P301+P317, P302+P352, P304+P340, P305+P351+P338, P319, P321, P330, P332+P317, P337+P317, P362+P364, P403+P233, P405, P501

Identifiers

CAS number
52-90-4
SMILES
N[C@@H](CS)C(=O)O
InChIKey
XUJNEKJLAYXESH-REOHCLBHSA-N
InChI
InChI=1S/C3H7NO2S/c4-2(1-7)3(5)6/h2,7H,1,4H2,(H,5,6)/t2-/m0/s1

Weigh it out

Type any one amount. The others follow from the molar mass and density.

Names and synonyms

19 names · show all
  • L-Cysteine
  • Cysteine, L-
  • Half-cystine
  • β-Mercaptoalanine
  • Thioserine
  • L-(+)-Cysteine
  • Propanoic acid, 2-amino-3-mercapto-, (R)-
  • Cystein
  • L-Alanine, 3-mercapto-
  • NSC 8746
  • (R)-2-Amino-3-mercaptopropanoic acid
  • (R)-Cysteine
  • 2-Amino-3-mercaptopropionic acid
  • L-Cys
  • E 920
  • (R)-2-Amino-3-sulfanylpropanoic acid
  • (2R)-2-Amino-3-sulfanylpropanoic acid
  • 2-Amino-3-mercaptopropanoic acid
  • 11: PN: WO2021055880 SEQID: 12 claimed protein

Work with Cysteine

Predict the NMR spectrum1H and 13C shifts with multiplicities Make a solutionWhat to weigh for any molarity and volume Check drug-likenessLipinski, Veber and lead-likeness Isotope patternExact mass and the mass spectrum pattern

Stereoisomers, salts and isotopologues

The same compound in another form: other stereochemistry, a salt or hydrate, the free acid or base, or an isotope-labelled version.

D-Cysteine921-01-7Enantiomer Cysteine3374-22-9Stereo not defined L-(+)-Cysteine hydrochloride52-89-1Salt (±)-Cysteine hydrochloride10318-18-0Salt, stereo not defined D-Cysteine hydrochloride32443-99-5Salt, enantiomer Cysteine hydrochloride monohydrate7048-04-6Salt DL-cysteine hydrochloride hydrate96998-61-7Salt, stereo not defined Dl-cysteine hydrochloride monohydrate116797-51-4Salt, stereo not defined

Similar compounds

Homocysteine454-29-563 % similar L-Homocysteine6027-13-063 % similar DL-Serine302-84-158 % similar D-Serine312-84-558 % similar L-Alpha,beta-Diaminopropionic acid4033-39-058 % similar 2,3-Diaminopropionic acid515-94-658 % similar Serine56-45-158 % similar Diaminopimelic acid583-93-758 % similar

Tanimoto similarity of circular fingerprints over the whole catalogue.

All similar compounds

Same formula

Cyclopropanesulfonamide154350-29-5

Elsewhere

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