Chemistry - Allantoin

General
Allantoin
Chemical name (2,5-Dioxo-4-imidazolidinyl) urea

Chemical formula	C₄H₆N₄O₃
Molecular weight	158.1164 g/mol
Appearance	?
CAS number	97-59-6
MSDS	Allantoin MSDS
SMILES	O=C1C(NC(=O)N1)NC(=O)N
Other names
?
Physical properties
Density and phase at STP	? g/cm³ (?)
Solubility	? in ?
Specific gravity	?
Crystal structure	?
pH (10% solution with water)	?
Acidity constant (pKa)	?
Thermal decomposition	? °C (? K)
Phase behavior
Melting point	239 °C
Boiling point	? °C (? K)
Triple point	? K (? °C) ? bar
Critical point	? K (? °C) ? bar
Heat of fusion (Δ_fusH)	? kJ/mol
Entropy of fusion (Δ_fusS)	? J/mol·K
Heat of vaporization (Δ_vapH)	? kJ/mol

Allantoin is a by-product of uric acid used as an anti-irritant in cosmetic products. Its chemical formula is C₄H₆N₄O₃.