Soluble Polymer Catalysts

Chiral molecules are those that exist in pairs of enantiomers, also referred to as stereoisomers (which can broadly be viewed as a left hand and right hand pair). Since pharmaceutical action is dependent on the “fit” of molecules with the body’s receptors, drugs for which both enantiomers have an action are generally less active than those for which a single enantiomer is active. Although in some drugs (e.g., Ibuprofen) both enantiomers have the same effect, it is more common for only one of the enantiomers (i.e., a single isomer) to have a specific action. Sometimes the other isomer is inert, but in a number of cases it has serious side effects (e.g., L-dopa for Parkinson’s, and some anti-arthritic drugs).

Consequently, both chiral forms of a drug must be tested for potential side effects, and there are legislative requirements for single enantiomer new drugs, with corresponding reduction in dosages, less wastage and a reduced risk of potential side effects. Production process developments for pharmaceuticals (and the intermediate compounds within the process) are being driven by these factors.

Technology

The current project is developing commercial processes using organocatalysts for chiral chemical production. In doing so, a number of existing metal catalyst processes will be replaced. There are environmental challenges associated with recovery of the metals used (e.g., iridium, rhodium, palladium, etc.), and also cost implications necessitated by the removal of unwanted metal residues from the resulting compounds.

New, solid-supported organocatalysts will be developed from inexpensive starting materials (chiral pool) with a particular emphasis that both enantiomers are available (a standard prerequisite for multipurpose catalysts). The catalysts will be synthesized using protocols developed by us in the last 3 years and anchored on a solid support. The new supported catalysts will be multifunctional and, therefore, applicable in various processes for manufacturing a wide range of pharmaceuticals, where the existing methodology is inadequate by industrial or environmental standards. This approach will address the area of chiral drugs, which currently constitute 1/3 of the world market of all pharmaceuticals, and whose global sales are expected to reach US$15 billion by 2009.

Benefits

• Recyclability of catalyst without loss of activity
• Enantioselectivity equivalent to commercially available products
• Modularity: different catalysts can be attached
• Possibility of synthesis on a chip
• Removability from the product: much simpler than current techniques: utilises mechanical filtration, therefore reduced costs, processing time and enhanced regulatory compliance
• Reactions work at room temperature
• Polymers can be bound to commercially available catalyst
• Continuous processing
• Parallel synthesis
• Good photochemical and thermal stability
• Clearly defined structures of the polymers: therefore synthesis can be easily reproduced

IP Status

A UK initial filing was made in November 2008.

Contact

If you are interested in finding out more about the Soluble Polymer Catalysts technology, please contact Lynne Brown on +44 (0)141 330 2731 or email l.brown@enterprise.gla.ac.uk