راضیه رضوی پاریزی

The present study aims to investigate tautomer stability of biomedicines with chemical structure of carbon compounds. In the present study from anticancer drugs, we selected 14 medicines having different mechanisms of action in the body. Then, their molecular-geometry structure was optimized usingthe B3LYP method and basic set 6-31 in the gas phase. After, for optimization and simulation of medicine action mechanism in human body, we added to medicine tautotmer factor group NH, SH, and OH, the simulated agents of drug receptor in the body. Finally, we identified the group is more stable in the body and shows better performance in terms of activity and the rate of energy. Comparing optimal energy of the main structure with tautotmer structure of Cladribine, Cyclophosphamide,Cytarabine,Dacarbazine,Mitoxantrone,Gemcitabine,and Flutamide , equal energy with energy difference ΔH=0 , we concluded that they play a similar role and Busulfan, Carmustine, Chlorambucil and Prednisone with energy difference Δ H=0.01 have no similar role. Altretamine, Tamoxifen and Letrozole indicated no tautomer structure . After simulation and optimization tests of action mechanism of drugs in the human body, the SH agent functioned more stable and more properly. After, the OH agent was more stable and the NH agent displayed the least stability.