| 摘要 |
<p>The present invention relates to process for the preparation of pure droxidopa of Formula (I) comprising: (a) reacting piperonal with glycine in the presence of a base in one or more organic solvents in the presence of a co-solvent followed by treating with acetic acid, to obtain a compound of Formula (VI), (b) hydrolyzing the compound of Formula (VI) with a base followed by reacting with an amino protecting agent to obtain a compound of Formula (V), (c) resolving the compound of Formula (V) with one or more resolving agents in one or more organic solvents to obtain a compound of Formula (IV), wherein, 'HA' refers to one or more resolving agents; (d) reacting the compound of Formula (IV) with an acid in one or more organic solvents to obtain a crystalline compound of Formula (III), (e) demethylating the compound of Formula (III) with a demethylating agent in the presence of a catalyst to obtain a compound of Formula (II), (f) deprotecting the compound of Formula (II) with a deprotecting agent comprising ammonium formate and Pd/C mixture to obtain the droxidopa of Formula (I); and (g) purifying the droxidopa to obtain pure droxidopa of Formula (I) and a process for the purification of droxidopa of Formula (I).</p> |
