Regioselective Acylation of Drug Intermediate for an Antileukaemic Agent

Regioselective Acylation of Drug Intermediate for an Antileukaemic Agent 

Synthesis of (S)-Benzyl-L-tert-Leucine Butyl Ester 

The amino acid (S)-tert-leucine (48) has been shown to be an important intermediate for a wide variety of pharmaceutically active molecules in the areas of antitumor, anti-inflammatory, and antiviral activity [42]. A number of routes to (S)-tert-leucine (48) have been developed, in particular the aqueous-based process from Degussa using asymmetric reductive animation of the prochiral keto acid with dehydrogenase and factor recycling [43, 44]. An industrial alternative was 

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