Polymorphic forms of a hydrochloride salt of (s)-2-(1-(9h-purin-6-ylamino)propyl)-5-fluoro-3-phenylquinazolin-4(3h)-one

A method of producing a composition comprising one or more polymorphs of a hydrochloride salt of a compound of Formula (I):

• comprising:
• combining a compound of Formula (I) with hydrochloric acid and a solvent to produce a composition comprising one or more polymorphs of the hydrochloride salt of the compound of Formula (I);
• or
• combining a hydrochloride salt of a compound of Formula (I) with a solvent to produce a composition comprising one or more polymorphs of the hydrochloride salt of the compound of Formula (I),
• wherein the solvent is selected from the group consisting of methanol, ethanol, water, isopropyl acetate, ethyl acetate, methyl tert-butyl ether, n-heptane, acetonitrile, acetone, 2-methyltetrahydrofuran, tetrahydrofuran, methyl isobutyl ketone, methyl ethyl ketone, dichloromethane, 2-propanol, l-propanol, 1-butanol, and any mixtures thereof.