Enzyme-catalyzed enantiomeric resolution of N-Boc-proline as the key-step in an expeditious route towards RAMP
作者:Masayuki Kurokawa、Takeyuki Shindo、Masumi Suzuki、Nobuyoshi Nakajima、Kohji Ishihara、Takeshi Sugai
DOI:10.1016/s0957-4166(03)00210-6
日期:2003.5
For the preparation of both enantiomers of N-carbamoyl-2-methoxymethylpyrrolidine, the precursors of Enders’ chiral auxiliaries, SAMP and RAMP, enzyme-catalyzed kinetic resolution of racemic N-carbamoyl, N-Boc, N-Cbz proline esters and prolinols were examined. B. licheniformis protease (subtilisin) preferentially hydrolyzed the (R)-carbamoylproline ester with an enantiomeric ratio (E) of 10. To a hydrophobic
对于两种对映体的制备Ñ -氨基甲酰基-2-甲氧基甲基,的恩德斯手性助剂,SAMP和RAMP的前体,酶催化的外消旋的动力学拆分Ñ -氨基甲酰基,Ñ -Boc,Ñ -Cbz脯氨酸酯和脯氨醇为检查。地衣芽孢杆菌蛋白酶(枯草杆菌蛋白酶)优先水解(R)-氨基甲酰基脯氨酸酯,对映体比率(E)为10。枯草杆菌蛋白酶对疏水性N -Cbz脯氨酸酯显示出较低的选择性(E = 2.8),相反,纯化的蛋白酶(同工酶A)对(S)-对映体(E= 13.6)。在实际意义上,南极衣原体脂肪酶B(Chirazyme L-2)可有效水解E> 100的N -Boc和N -Cbz衍生物。(R)-N-氨基甲酰基-2-甲氧基甲基吡咯烷酮的ee通过在N -Boc-脯氨醇阶段重结晶而提高到> 99.9%,该阶段衍生自(R)-N -Boc-脯氨酸甲酯(98.7 %ee)通过外消旋底物的制备规模的酶催化拆分(49%收率)。