Due to hydrogen bonding Quinizarin is a orange-red crystalline compound. It is soluble in ethanol, diethyl ether, benzene and hot water. It has an only limited solubility in cold water. Quinizarin can be oxidized to form 1,4,9,10-anthradiquinone by led tetraacetate. Solution Due to hydrogen bonding Quinizarin is a orange-red crystalline compound. It is soluble in ethanol, diethyl ether, benzene and hot water. It has an only limited solubility in cold water. Quinizarin can be oxidized to form 1,4,9,10-anthradiquinone by led tetraacetate..