Loading patent…
AssigneeEgis Gyogyszergyar Rt.
InventorsGyorgy Somogyi, Peter Botka, Gyula Horvath, Antal Simay, Roozsa Gyenge, Imre Moravcsik, Erno Orban, Tamas Hamori, Jeno Korosi, Csilla Kiss, Tibor Balogh, Maria Bidlo nee Igloi, nee Dievald; Emilia Uskert
Estimating the term…
The invention relates to a process for the preparation of 1-(3-chlorophenyl)-4-methyl-7,8-dimethoxy-5 H-2,3-benzodiazepine of formula (I) ##STR1## in high purity and in a quality suitable for pharmaceutical purposes. According to the invention the reaction of 1 mole of 2-acetonyl-3'-chloro-4,5-dimethoxybenzophenone of formula (II) ##STR2## with 3-7 moles of hydrazine hydrate in an organic solvent or in a mixture of organic solvents at a temperature between 15.degree. C. and 85.degree. C. is carried out in the absence of air oxygen, optionally in the presence of water. The crude product is then recrystallized from an aliphatic alcohol containing 1 to 5 carbon atom(s).
A process for the preparation of 1-(3-chlorophenyl)-4-methyl-7, 8-dimethoxy-5H-2,3-benzodiazepine of formula (I) ##STR8## in high purity and in a quality suitable for pharmaceutical purposes, said process comprising reacting 1 mole of 2-acetonyl-3'-chloro-4, 5-dimethoxybenzophenone of formula (II) ##STR9## with 3 to 7 moles of hydrazine hydrate in an organic solvent or in a mixture of organic solvents, at a temperature between 15.degree. C. and 85.degree. C. in the absence of oxygen and optionally in the presence of water, and subsequently recrystallizing the crude product from an aliphatic alcohol containing 1 to 5 carbon atom(s), wherein the total contamination content in said 1-(3-chloro-phenyl)-4-methyl-7, 8-dimethoxy-5H-2,3-benzodiazepine does not exceed 0.3% by mass.
Dependencies are inferred from the claim text.