Process for the preparation of Rivastigmine
AssigneeAlembic Limited
InventorsPandurang Balwant Deshpande, Kishore Khemani, Bharat Becharbhai Boda, Tushar Rajnikant Shah, Hitarth Harshendu Acharya, Parven Kumar Luthra
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Abstract
The present invention relates to an improved process for preparation of Rivastigmine of formula (I) or pharmaceutically acceptable salts thereof comprising a step of N-methylation of compound of formula (III), wherein R1=R2=H or R1=H and R2=CH3 or an acid addition salt thereof, using paraformaldehyde in the presence of Raney Nickel and hydrogen in a suitable solvent to obtain compound of formula (II).
Claims10
A process for the preparation of Rivastigmine of formula (I) or pharmaceutically acceptable salts thereof, comprising:
- (a) N-methylation of a compound of formula (III), wherein R1=R2=H or R1=H and R2=CH3 or an acid addition salt thereof, using paraformaldehyde in the presence of Raney Nickel and hydrogen in a suitable solvent to obtain a compound of formula (II)
- (b) optically resolving the compound of formula (II) to obtain a desired isomer (II′)
- (c) converting the compound of formula (II′) to Rivastigmine of formula (I) and optionally converting it to pharmaceutically acceptable salts thereof
A process for the preparation of Rivastigmine of formula (I) or pharmaceutically acceptable salts thereof, comprising a step of N-methylation of a compound of formula (III), wherein R1=R2=H or R1 =H and R2=CH3 or an acid addition salt thereof, using paraformaldehyde in the presence of Raney Nickel and hydrogen in a suitable solvent to obtain a compound of formula (II) and thereafter converting the compound of formula (II) to Rivastigmine of formula (I)
A process for preparation of a compound of formula (II) comprising:
- N-methylation of a compound of formula (III), wherein R1=R2=H or R1=H and R2=CH3 or an acid addition salt thereof, using paraformaldehyde in the presence of Raney Nickel and hydrogen in a suitable solvent to obtain compound of the formula (II)
Dependencies are inferred from the claim text.