Trazodone hydrochloride tetrahydrate

Sasaki, K. Suzuki, H. Nakagawa, H. Physicochemical characterization of trazodone hydrochloride tetrahydrate. Chem. Pharm. Bull. 1993, 41, 325-328. 

Typically, hydrates are obtained by recrystallization from water. For example, trazodone hydrochloride tetrahydrate was prepared by dissolving the anhydrate in hot distilled water, allowing the solution to remain at room temperature overnight, and storing the collected crystals at 75% relative humidity and 25°C until they reached constant weight [64]. 

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