Organophosphorus compounds have wide range of applications in the industrial, agricultural and medicinal chemistry owing to their unique physicochemical and biological properties. Their utility as reagents and potential synthons in organic synthesis is gaining increased attention. This book covers diverse range of synthetic protocols, bioactivity studies and analytical methodologies for assessing ¿-aminophosphonates and tetraphenyl (phenylamino) methylene bisphosphonates including nuclear magnetic resonance and mass spectrometry. Accomplishment of ¿-aminophosphonates in cancer chemotherapy. Accomplished synthesis of tetraphenyl (phenylamino)methylene bisphosphonates (TPM-BPs) and investigated their influence on inhibition of osteoclasts. We hope that this book will go some way towards reinvigorating interest in these fascinating compounds. The author sincerely thanks Scholars Press for their encouragement and Publishing.