Properties: white or almost white crystalline powder, odorless, slightly soluble in ethanol, very little soluble in chloroform, insoluble in water, dissolved in 0.1NNaOH solution. Other indicators: Content (chemical assay) ≥ 99.0% Related substances <1.0% Loss on drying ≤ 0.5% Residue on ignition <0.1% Heavy metal ≤ 0.001%