Dendronized Supports as Synthetic Intermediates

Although part of the dendron-support hybrids are prepared for the subsequent use as new materials, in other cases these constructs are only intermediates en route to production of soluble dendrons. In these cases, the solid-phase synthesis technique was chosen as a synthetic approach to the preparation of dendrons, designated for application in solution. 

Some of these dendrons are cleaved immediately after formation others are used as supported templates for preparation of soluble dendritic conjugates, which are initially constructed on support, but thereafter are cleaved together with the dendritic component. In some comparative studies, this approach showed better results than the preparation of the dendritic conjugate in solution.  

Another two types of supported dendrons used for generation of dendritic gene delivery devices are the polystyrene-bound polyurea and peptoid dendrons developed by Bradley and coworkers. They demonstrated that these dendrons, once cleaved from the support, complex efficiently plasmid DNA and transfect it successfully into cells. The highest efficiency (comparable or better than that displayed by the commercial transfection agent Superfect) was observed for bis-G3 dendrons capped with lysine. In general, the efficiency increased with the dendron generation (positive effect). 

DENDRITIC MOLECULES ON SOLID SUPPORT SOLID-PHASE SYNTHESIS AND APPLICATIONS 

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