Abstract: A continuous process for the alkylation of tertiary amines and, in particular, to a continuous process for the quaternization of cyclic tertiary amines useful for the preparation of cyclic quaternary ammonium salts with high purity is described.

Abstract: A stable crystalline form of tiotropium bromide, and a process for its preparation with high purity.

Abstract: A process for the preparation of the stable, amorphous calcium salt of (6S)—N(5)-methyl-5,6,7,8-tetrahydrofolic acid of the formula V, and a stable, amorphous calcium salt of (6S)—N(5)-methyl-5,6,7,8-tetrahydrofolic acid of the formula V are provided.

Abstract: A process for the preparation of the stable, amorphous calcium salt of (6S)-N(5)-methyl-5,6,7,8-tetrahydrofolic acid of the formula V, and a stable, amorphous calcium salt of (6S)-N(5)-methyl-5,6,7,8-tetrahydrocolic acid of the formula V are provided.

Abstract: There is provided a stable, crystalline (6S)-N(5)-methyl-5,6,7,8-tetrahydrofolic acid of the formula IV, This compound belongs to the family of reduced folates which are useful in vitaminic and oncological field.

Abstract: A process for the preparation of an aqueous solution of the calcium salt of (6S)-N(5)-methyl-5,6,7,8-tetrahydrofolic acid, whereby (6S)-5,6,7,8-tetrahydrofolic acid having a content of the corresponding (6R)-diastereoisomer in the range from 4% by weight to 8% by weight is methylated in water comprises: treating the methylated reaction mixture with calcium chloride; crystallizing the calcium salt of (6RS)-N(5)-methyl-5,6,7,8-tetrahydrofolic acid from the resulting aqueous solution; and obtaining an aqueous solution of the calcium salt of (6S)-N(5)-methyl-5,6,7,8-tetrahydrofolic acid.

Abstract: The inventive method for the production of crystalline (6RS)-N(5)-formyl-5,6,7,8-tetrahydrofolic acid or amorphic (6S)-N(5)-formyl-5,6,7,8-tetrahydrofolic acid is characterized in that an aqueous solution of (6RS)- or (6S)-calcium folinate, which has a temperature of 40° C. to 50° C., and an aqueous solution of hydrochloric acid or acetic acid are added to stirred water having a temperature of 2° C. to 12° C., such that the temperature is kept at 2° C. to 12° C. in the mixture thus obtained when the two above-mentioned solutions are added and the pH value is kept at 2,5 to 3,5, the solid thus arising is isolated by means of filtration or centrifugation, the solid is initially washed with cold water and then with an aqueous organic solvent, and the washed solid, i.e. crystalline (6RS)-N(5)-formyl-5,6,7,8-tetrahydrofolic acid or amorphous (6S)-N(5)-formyl-5,6,7,8-tetrahydrofolic acid is dried at reduced pressure and obtained.