L-Cysteine

InChI

1S/C3H7NO2S/c4-2(1-7)3(5)6/h2,7H,1,4H2,(H,5,6)/t2-/m0/s1

InChI key

XUJNEKJLAYXESH-REOHCLBHSA-N

SMILES string

N[C@@H](CS)C(O)=O

assay

≥98.5% (RT)

optical activity

[α]20/D +7.6±0.5°, c = 5% in 5 M HCl

impurities

≤0.5% foreign amino acids

ign. residue

≤0.1% (as SO₄)

loss

≤0.1% loss on drying, 110 °C

mp

240 °C (dec.) (lit.)

anion traces

chloride (Cl^-): ≤100 mg/kg, sulfate (SO₄^2-): ≤100 mg/kg

cation traces

Ca: ≤10 mg/kg, Cd: ≤5 mg/kg, Co: ≤5 mg/kg, Cr: ≤5 mg/kg, Cu: ≤5 mg/kg, Fe: ≤5 mg/kg, K: ≤50 mg/kg, Mg: ≤5 mg/kg, Mn: ≤5 mg/kg, NH₄⁺: ≤500 mg/kg, Na: ≤100 mg/kg, Ni: ≤5 mg/kg, Pb: ≤5 mg/kg, Zn: ≤5 mg/kg