No abstract

A one pot synthetic approach to amino acid based chiral dendrimers was shown to give good yields for dendrimers with peptide linkages. Using this synthetic strategy, modiÐcation of the peripheral functionality is possible, as is the substitution of other amino acids to give mixed amino acid based dendrimers. Immobilization of our dendrimers was accomplished using a coupling method involving the carboxy derivatised dendrimers with an aminopropyl modiÐed silica. The use of 2-ethoxy-1-ethoxy-1,2-dihydroquinoline in a one pot protocol gave enhanced reaction conditions from which silicas bearing very high levels of dendrimer were obtained. Solid state NMR analysis substantiated that the dendrimers were bound to the silica and that they appeared to be structurally intact. These immobilised chiral dendrimers constitute a new class of chiral stationary phases for use in HPLC.

No abstract

This paper reports on some of the key outcomes of a 3 year £1.5m Technology Strategy Board (TSB) funded research programme to develop a small footprint, versatile, counter-current chromatography purification technology and methodology which can be operated at a range of scales in both batch and continuous modes and that can be inserted into existing process plant and systems. Our consortium, integrates technology providers (Dynamic Extractions) and the scientific development team (Brunel) with end user needs (GSK & Pfizer), addressing major production challenges aimed at providing flexible, low capital platform technology driving substantial cost efficiency in both drug development and drug manufacturing processes. The aims of the Technology Strategy Board's high value manufacturing programme are described and how the academic/industry community were challenged to instigate step changes in the manufacturing of high value pharmaceuticals. This paper focusses on one of the themes of the TSB research programme, "Generate a Comprehensive Applications Portfolio". It outlines 15 applications from this portfolio that can be published in the public domain and gives four detailed case studies illustrating the range of application of the technology on the separation of (1) isomers, (2) polar compounds, (3) crude mixtures and (4) on the removal of impurities. Two of these case studies that were scaled up demonstrate between 10 and 20% lower solvent usage and were projected to have significant cost savings compared to conventional solid phase silica gel chromatography at procss scale demonstrating that the latest high performance countercurrent chromatography technology is a competitive platform technolgy for the pharmaceutical industry.