A key step in the manufacture of (S)-allysine ethylene acetal is the L-acylase enzyme catalysed resolution of the racemic N-benzoyl-protected amino acid. This poster describes the selection and cloning of the L-acylase activity from wild type Thermoccocus litoralis into two high yielding bacterial expression systems: Escherichia coli and Pseudomonas fluorescens. Comparison of the titres of enzyme from these systems led to selection of P. fluorescens for scale up, culminating in enzyme production at 10,000 L scale. Ready availability of the catalyst allowed development of the process to (S)-allysine ethylene acetal, and a manufacturing campaign that produced multi-hundred kilograms of this valuable chiral intermediate in >99% enantiomeric excess (ee) and >99% chemical purity.
P39: Large scale enzyme manufacture: Key to the synthesis of (S)-allysine ethylene acetal
Sunday, July 24, 2011
Grand Ballroom, 5th fl (Sheraton New Orleans)
The compound, (S)-2-amino-5-[1,3]dioxolan-2-yl-pentanoic acid [(S)-allysine ethylene acetal], is a key intermediate in a number of angiotensin-I converting enzyme (ACE) and neutral endopeptidase (NEP) inhibitors currently in clinical trials. Through a combination of our hydroformylation and biocatalysis technologies we have developed an efficient five step synthetic route to this material starting from crotonaldehyde.