Asymmetric Synthesis of (R)-Nilvadipine and (S)-NB 818 via Regioselective Bromination of Chiral 1,4-Dihydropyridines as a Key Step and Enzymatic Resolution of Racemic 2-Hydroxymethyl-1,4-dihydropyridine Derivatives.
Asymmetric Synthesis of (R)-Nilvadipine and (S)-NB 818 via Regioselective Bromination of Chiral 1,4-Dihydropyridines as a Key Step and Enzymatic Resolution of Racemic 2-Hydroxymethyl-1,4-dihydropyridine Derivatives.
Enzymatic synthesis of optically active 2-carbamoyl-oxymethyl-1,4-dihydropyridines, (R)-(+)- and (S)-(−)-NB 818
作者:Hirosato Ebiike、Kaori Maruyama、Kazuo Achiwa
DOI:10.1016/s0957-4166(00)82100-x
日期:1992.9
Racemic dihydropyridines were resolved by enzyme-catalyzedhydrolysis in an organic solvent saturated with water. The chiral derivatives obtained were converted to (S)- and (R)-NB 818.
Asymmetric Synthesis of (R)-Nilvadipine and (S)-NB 818 via Regioselective Bromination of Chiral 1,4-Dihydropyridines as a Key Step and Enzymatic Resolution of Racemic 2-Hydroxymethyl-1,4-dihydropyridine Derivatives.
Optically active 2-hydroxymethyl-1, 4-dihydropyridines were obtained by lipase-catalyzed hydrolysis or transesterification of racemic materials. Chiral NB 818 and nilvadipine have been synthesized from chiral 2-hydroxymethyl-1, 4-dihydropyridine. On the other hand, chiral 1, 4-dihydropyridines obtained from prochiral substrates have been converted into (S)-NB 818 and (R)-nilvadipine via regioselective bromination of methyl groups under mild conditions.