cis-Urocanic acid

≥98% (HPLC), solid (fluffy)

cis-3-(1H-imidazol-4-yl)-2-propenoic acid, cis-UCA
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
MDL number:
PubChem Substance ID:

Quality Level


≥98% (HPLC)


solid (fluffy)

storage condition

protect from light




H2O: >10 mg/mL

storage temp.


SMILES string




InChI key



cis-Urocanic acid (cis-UCA) has been used:
  • to study its protective effects on autoimmune encephalomyelitis
  • in sample preparation to study the distribution of skin chemical components by line illumination Raman microscopy technique in Line-focus illumination mode
  • as a standard to study the levels of cis-UCA and to check its effect on immune response in multiple sclerosis patients


10, 50 mg in glass bottle

Biochem/physiol Actions

cis-Urocanic acid (cis-UCA) affects the immune cells of the body and is excreted in the urine due to photoisomerization. It inhibits tumor immunity through photocarcinogenesis in mice. cis-Urocanic acid has been studied to prevent UV-radiation-induced DNA damage leading to skin cancer.
cis-Urocanic acid, a 5-HT agonist, is a product of UV isomerization of trans-urocanic acid in skin, which leads to immunosuppression via activation of 5-HT2A receptor.

Preparation Note

cis-Urocanic acid is soluble in water at a concentration that is greater than 10 mg/ml.

Personal Protective Equipment

dust mask type N95 (US),Eyeshields,Gloves


NONH for all modes of transport

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis

Certificate of Origin

Jorge Correale et al.
Journal of neuroimmunology, 261(1-2), 134-140 (2013-06-27)
The role of cis-urocanic acid (UCA) as a UV-mediated immunomodulator in MS patients was investigated. Plasma levels of cis-UCA were significantly lower in MS patients compared to controls. Stimulation of MBP- and MOG-specific T cells in the presence of cis-UCA...
S Beissert et al.
Journal of immunology (Baltimore, Md. : 1950), 167(11), 6232-6238 (2001-11-21)
UV radiation induces skin cancer primarily by its DNA-damaging properties, but also by its capacity to suppress the immune system. The photoisomer of urocanic acid (UCA), cis-UCA, is an important mediator of UV-induced immunosuppression and is involved in the inhibition...
High-speed line-focus Raman microscopy with spectral decomposition of mouse skin
Ilchenko O, et al.
Vibrational Spectroscopy, 83, 180-190 (2016)
Hanna-Mari Jauhonen et al.
Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie, 255(12), 2357-2362 (2017-08-26)
Our purpose was to investigate the effect of locally administered cis-urocanic (cis-UCA) in two experimental models of allergic conjunctivitis. The compound 48/80 (C48/80)-induced ocular irritation model (IgE-independent) and the ovalbumin (OA)-induced ocular allergy model (IgE-mediated) were used to test and...
Amy A Irving et al.
BMC neuroscience, 18(1), 8-8 (2017-01-07)
Ultraviolet B irradiation confers strong resistance against experimental autoimmune encephalomyelitis, a model of multiple sclerosis. This protection by ultraviolet B is independent of vitamin D production but causes isomerization of urocanic acid, a naturally occurring immunosuppressant. To determine whether UCA...
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