Engineering a carbonyl reductase for the scalable preparation of (S)‐3‐Cyclopentyl‐3‐hydroxypropanenitrile, the key building block of ruxolitinib

3 years ago

Engineering a carbonyl reductase for the scalable preparation of (S)‐3‐Cyclopentyl‐3‐hydroxypropanenitrile, the key building block of ruxolitinib

Yunfeng Cui, Liangyan Zhu, Xi Chen, Jinhui Feng, Qiaqing Wu, Dunming Zhu

( S )- 3-Cyclopentyl-3-hydroxypropanenitrile is the key precursor for the synthesis of ruxolitinib. The bioreduction of 3-cyclopentyl-3-ketopropanenitrile ( 1a ) offers an attractive method to access this important compound. A carbonyl reductase (PhADH) from Paraburkholderia hospita catalyzed the reduction of 1a giving the ( S )-alcohol ( 1b ) with 85% ee. Rational engineering of PhADH resulted in a double mutant H93C/A139L, which enhanced the enantioselectivity from 85% to >98%, as well as a 6.3-fold improvement in the specific activity. The bioreduction of 1a was performed at 200 g/L (1.5 M) substrate concentration, leading to isolation of ( S )- 1b in 91% yield. Similarly, using this mutant enzyme 3-cyclohexyl-3-ketopropanenitrile ( 2a) and 3-phenyl-3-ketopropanenitrile ( 3a ) were reduced at high concentration affording the corresponding alcohols in >99% ee, and 90% and 92% yield, respectively. The results showed that the variant H93C/A139L was a powerful biocatalyst for reduction of β-substituted-β-ketonitriles.

Publisher URL: https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cbic.202100589

DOI: 10.1002/cbic.202100589