Racemic mixtures among pharmaceuticals

Rhizopus arrhizus dead mycelium was found to be very active in organic solvents as a naturally immobilized lipase. Triglycerides hydrolysis and interesterification, esters and glycerides synthesis, natural flavour esters preparation and racemic mixtures resolution in pharmaceutical drugs synthesis are among the successfully designed processes, each of one with a specific reactional medium. 

A number of the new drugs under development are chiral. The two main reasons for this choice by pharmaceutical companies are the regulatory constraints to assess the properties of single enantiomers, even if the racemic mixture is developed, and the scientific evidence that enantiomers often have very different and, sometimes, opposite pharmacologic effects. Among the numerous techniques available today to industrial chemists, asymmetric synthesis has been used successfully to obtain chiral compounds. From an industrial point of view, asymmetric catalysis is becoming the preferred approach because of its low environmental impact and high potential productivity. 

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