Preparation of rivastigmine and its salts
AssigneeDr. Reddy's Laboratories, Inc.
InventorsVenkata Naga Brahmeswara Rao Mandava, Venkata Reddy Vajrala, Ganesh Varanasi, Vijay Kumar Adla, Mukund Reddy Jambula, Vijaypal Reddy Kanumathi Reddy
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Abstract
There are provided processes for making rivastigmine. In one embodiment, the process includes reacting S-(−)-[1-(3-hydroxyphenyl)ethyl]dimethylamine with N-ethyl-N-methyl carbamoyl chloride in the presence of an organic base to obtain a free base of rivastigmine.
Claims17
A process for preparing rivastigmine or a salt thereof comprising reacting S-(−)-[1-(3-hydroxyphenyl)ethyl]dimethylamine with N-ethyl-N-methyl carbamoyl chloride in the presence of an organic base to obtain a free base of rivastigmine, wherein the organic base is pyridine, lutidine, triethylamine, dimethylaminopyridine (DMAP), dicyclohexylamine, or diisopropylethylamine.
A process for preparing rivastigmine or a salt thereof comprising reacting S-(−)-[1-(3-hydroxyphenyl)ethyl]dimethylamine with less than one molar equivalent of N-ethyl-N-methyl carbamoyl chloride.
Dependencies are inferred from the claim text.