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 R
1
=R
2
=H or R
1
=H and R
2
=CH
3
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).
PROCESS FOR PRODUCING (S)-3-[(1-DIMETHYLAMINO)ETHYL] PHENYL-N-ETHYL-N-METHYL-CARBAMATE VIA NOVEL INTERMEDIATES
申请人:Dubey Shailendra Kumar
公开号:US20120022281A1
公开(公告)日:2012-01-26
Disclosed herein are novel intermediates and process for large scale production of (S)-3-[(1-dimethylamino)ethyl]phenyl-N-ethyl-N-methyl-carbamate (rivastigmine) or its pharmaceutically acceptable salts employing the novel intermediates. Further provided are methods for producing the novel intermediates thereof.
BIOCATALYSTS AND METHODS FOR THE SYNTHESIS OF (S)-3-(1-AMINOETHYL)-PHENOL
申请人:Cabirol Fabien
公开号:US20130089898A1
公开(公告)日:2013-04-11
The present disclosure provides engineered transaminase polypeptides having improved properties as compared to naturally occurring transaminases including the ability of converting the substrate, 3′-hydroxyacetophenone to (S)-3-(1-aminoethyl)-phenol in enantiomeric excess and high percentage conversion. Also provided are polynucleotides encoding the engineered transaminases, host cells capable of expressing the engineered transaminases, and methods of using the engineered transaminases to synthesize (S)-3-(1-aminoethyl)-phenol and related compounds useful in the production of active pharmaceutical ingredients.