The drug discovery process is a very complex and includes an interdisciplinary effort for designing effective and commercially feasible drug, Combination of rational drug design and structure biology leads to discovery of novel therapeutic agents. In pharmaceutical, medicinal as well as in other scientific research ; a computer plays a very essential role, even in development of new compound in quest for better therapeutic agents and for this purpose computer aided drug design (CADD) centre work with collaboration between structure biologists, biophysicists and computational scientists for discovery of new chemical entities .