Abstract: The present invention relates to the characterization of a new crystal modification III of torasemide, to a process for the preparation thereof by the use of controlled acidifying of alkaline solutions of torasemide with inorganic or organic acids with or without addition of a crystal seed, to its use as a raw material for the preparation of the crystal modification I of torasemide and of pharmaceutically acceptable salts of torasemide as well as to pharmaceutical forms containing this new crystal modification III of torasemide.

Abstract: The present invention relates to the characterization of a new crystal modification III of torasemide, to a process for the preparation thereof by the use of controlled acidifying of alkaline solutions of torasemide with inorganic or organic acids with or without addition of a crystal seed, to its use as a raw material for the preparation of the crystal modification I of torasemide and of pharmaceutically acceptable salts of torasemide as well as to pharmaceutical forms containing this new crystal modification III of torasemide.

Abstract: The invention relates to a new process for obtaining a completely pure oxytetracycline which does not contain any acetyldecarboxamidooxytetracycline as ingredient. In glacial acetic acid there is suspended under stirring oxytetracycline hydrochloride, or alternatively, oxytetracycline dihydrate under addition of an equimolar quantity of hydrogen chloride in the form of concentrated hydrochloric acid. The stirring is continued for 5 hours, the formed oxytetracycline hydrochloride acetate precipitate is filtered, washed with glacial acetic acid and acetone, whereupon it is dried under reduced pressure at a temperature up to 40.degree. C. till constant weight. Oxytetracycline hydrochloride acetate ##STR1## is a new compound and may be used as intermediate in the above process.

Abstract: Starting from cis-2-butene-1,4-diol, via the 4,7-dihydro-1,3-dioxepin and trans-6-acylamino-5-chloro-1,3-dioxepans the novel tetrahydro-[1,3]-dioxepino[5,6-b]-azirines were synthesized, and therefrom the novel hypoglycaemically active N-sulfonyl-tetrahydro-[1,3]-dioxepino[5,6-b]azirines. The inventive compounds are valuable intermediates in the synthesis of other, biologically active substances.