Abstract: The invention relates to non-hydrated fexofenadine hydrochloride which can be obtained from a fexofenadine base and hydrogen chloride, according to the reaction conditions, either in the form of a novel polymorph (“form A”), in an amorphous form, or in the form of a mixture of different polymorphs. Said novel polymorph (“form A”) can be used as a therapeutic active ingredient and can be processed to form a pharmaceutical containing the same and a pharmaceutically acceptable carrier. Said pharmaceutical is suitable for use as an antihistaminic agent, an antiallergic agent and/or a bronchodilating agent.

Abstract: Phosphoric acid diester 2,5-dioxo-4,4-diphenylimidazolidin-1-ylmethyl esters, both of whose ester groups can be selectively cleaved, are obtained by converting 3-(hydroxymethyl)-5,5-diphenylimidazolidine-2,4-dione to an alkylsulfonate or arylsulfonate and reacting this with a phosphoric acid diester whose ester groups can be selectively cleaved from the reaction product. The two ester groups can be selectively cleaved from the phosphoric acid diesters obtained and the resulting product can be converted to 5,5-diphenyl-3-[(phosphonooxy)methyl]imidazolidine-2,4-dione disodium salt. The latter is an anticonvulsive, antiepileptic and antiarrhythmic known under the abbreviated name of sodium fosphenytoin.

Abstract: Phosphoric acid diester 2,5-dioxo-4,4-diphenylimidazolidin-1-ylmethyl esters, both of whose ester groups can be selectively cleaved, are obtained by converting 3-(hydroxymethyl)-5,5-diphenylimidazolidine-2,4-dione to an alkylsulfonate or arylsulfonate and reacting this with a phosphoric acid diester whose ester groups can be selectively cleaved from the reaction product. The two ester groups can be selectively cleaved from the phosphoric acid diesters obtained and the resulting product can be converted to 5,5-diphenyl-3-[(phosphonooxy)methyl]imidazolidine-2,4-dione disodium salt. The latter is an anticonvulsive, antiepileptic and antiarrhythmic known under the abbreviated name of sodium fosphenytoin.

Abstract: The invention relates to non-hydrated fexofenadine hydrochloride which can be obtained from a fexofenadine base and hydrogen chloride, according to the reaction conditions, either in the form of a novel polymorph (“form A”), in an amorphous form, or in the form of a mixture of different polymorphs. Said novel polymorph (“form A”) can be used as a therapeutic active ingredient and can be processed to form a pharmaceutical containing the same and a pharmaceutically acceptable carrier. Said pharmaceutical is suitable for use as an antihistaminic agent, an antiallergic agent and/or a bronchodilating agent.