No abstract

During the development of a new route to AZD2563 DSP (DSP ) disodium phosphate), a selective enzyme-catalysed hydrolysis of a 1,2-diester moiety to produce the secondary monoester was developed. Apart from two esters, the target molecule also contained three further functional groups prone to hydrolysis. A major challenge to the chosen approach was the very facile rearrangement of the desired secondary monoester product to the undesired primary monoester. This rearrangement was found to be catalysed by a wide range of chemicals and inorganic materials usually considered as inert. The unique selectivity and mild operating conditions of biocatalysis allowed the desired reaction to be developed and successfully scaled up.