Molecular modeling studies of fused pyrimidine derivatives at various receptors

Fused pyrimidine derivatives have been the center of attention due to their diverse biological potential for quite a long now. One reason for such an interesting pharmacological profile of this class of heterocycles is their ability to mimic physiological molecules such as purines. Fused pyrimidines are usually considered as bioisosteres of purines and therefore it is easier to design molecules with equal or higher binding affinity for a biological target that has a purine-based physiological ligand. There are more than 40 drugs pertaining to fused pyrimidine scaffolds approved by the FDA for the management of different pathological conditions. Hence in this chapter, an overview of the molecular modeling-based information of all the FDA-approved drugs of fused pyrimidines is presented. Binding mode information of each drug in their respective molecular targets provides insights into how a pharmacologically “gifted” scaffold is tailored to fit in with a better binding affinity.