合成路线1

A synthesis of pitavastatin has been reported: Cyclization of 2-amino-4'-fluorobenzophenone (I) with 3-cyclopropyl-3-oxopropionic acid methyl ester (II) by means of H2SO4 in refluxing acetic acid or methanesulfonic acid in refluxing benzene gives 2-cyclopropyl-4-(4-fluorophenyl)quinoline-3-carboxylic acid methyl ester (III), which is reduced with DIBAL in toluene to yield the carbinol (IV). Oxidation of compound (IV) with PCC and AcONa in dichloromethane affords carbaldehyde (V), which is condensed with tributylstannane (VI) by means of BuLi in THF to provide the enol ether (VII). Hydrolysis of (VII) by means of TsOH in THF/water gives the unsaturated carbaldehyde (VIII), which is condensed with acetoacetic ester (IX) by means of NaH and BuLi in THF to yield the 5-hydroxy-3-oxoheptenoic ester derivative (X). Stereoselective reduction of the oxo group of (X) by means of diethylmethoxyborane and NaBH4 in THF/methanol gives the racemic syn-dihydroxy compound (XI) in a syn/anti ratio of 98:2. Finally, compound (XI) is hydrolyzed with NaOH in aqueous ethanol to yield racemic pitavastatin sodium. Alternatively, the unsaturated carbaldehyde (VIII) can also be obtained by reaction of carbaldehyde (V) with phosphonate (XII) by means of NaOH in toluene/water to give the unsaturated nitrile (XIII), which is finally reduced with DIBAL in toluene to afford the target carbaldehyde (VIII).