Colorless or slightly purplish-yellow crystals. Melting point 52.9-53.6 °C, boiling point 302 °C, 191 °C (2.0kPa), 166 °C (0.67kPa), can volatilize with water vapor. Soluble in hot water, soluble in ethanol, ether chloroform and methanol, slightly soluble in cold water.