Eprova Ag

Neotherapeutics, Inc.

Hans Rudolf M&uuml;ller

Rudolf Moser

Martin Ulmann

Thomas Ammann

Heinrich Bollinger

Alvin Jerald Glasky

Martin Kurz

Peter Schwaninger

Pure and extremely stable crystalline (6R)-tetrahydrofolic acids, absolutely inert even when exposed to air and elevated temperature without stabilizers being added, are prepared by a crystallization process at a pH of &gE;2.

Stable crystalline (6R) -tetrahydrofolic acid

The bifunctional compound N-4-carboxyphenyl-3-(6-oxohydropurin-9-yl) propanamide monopotassium salt occurs in a number of crystal forms which differ in their stability. Of these forms, the most stable is designated Type I, which is a monopotassium salt monohydrate in which the water is held as water of crystallization. Other crystalline forms, designated Type II and Type III, convert to Type I. Methods are disclosed for the synthesis of Type I and for the conversion of Type II or Type III to Type I.

Crystal forms of 9-substituted hypoxanthine derivatives

Pure and extremely stable crystalline (6S)- and (6R)-tetrahydrofolic acids, absolutely inert even when exposed to air and elevated temperature without stabilizers being added, are prepared by a crystallization process at a pH of &gE;3.5 for the preparation of crystalline (6S)-tetrahydrofolic acid and at a pH of &gE;2 for the preparation of crystalline (6R)-tetrahydrofolic acid.

Stable crystalline (6S)-  and (6R)-tetrahydrofolic acid

With the present method, a process which can be employed industrially can be used for the first time for the direct production of aminocyanoacetamide. The method is based on the reaction of cyanoacetamide with nitrites to form nitrosocyanoacetamide at a pH of around 2 and on the subsequent catalytic hydrogenation of nitrosocyanoacetamide to form aminocyanoacetamide.

Growing community of inventors

Schaffhausen, Switzerland

Hans Rudolf Müller

Growing community of inventors

Schaffhausen, Switzerland

Hans Rudolf M&uuml;ller

Hans Rudolf Müller