The resulting scaffold structures are characterized by their rigidity, stereochemical and functional group complexity, high density and diversity of functionality radially arrayed from which to generate highly diversified libraries, and by {HEAD ~ the minimal need} to employ protecting {TAIL ~ groups} during the synthesis of the scaffold structures and combinatorial libraries 
to employ protecting
The resulting scaffold structures are characterized by their rigidity , stereochemical and functional group complexity , high density and diversity of functionality radially arrayed from which to generate highly diversified libraries , and by { HEAD ~ the minimal need } to employ protecting { TAIL ~ groups } during the synthesis of the scaffold structures and combinatorial libraries
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