Isoconversional approach for non-isothermal decomposition of un-irradiated and photon-irradiated 5-fluorouracil

6^th World Congress on Medicinal Chemistry and Drug Design

June 07-08, 2017 Milan, Italy

Refaat M Mahfouz, Hala Sh Mohamed and Abdel Rahman A Dahy

Assiut University, Egypt

Posters & Accepted Abstracts: Med Chem (Los Angeles)

Abstract :

Kinetic analysis for the non-isothermal decomposition of un-irradiated and photon-beam-irradiated 5-fluorouracil (5-FU) as anti-cancer drug, was carried out in static air and nitrogen atmospheres. Thermal decomposition of 5-FU, proceeds in two steps. One minor step in the range of (270-280�?ºC) followed by the major step in the temperature range of (285-360�?ºC). The non-isothermal data for un-irradiated and photon-irradiated 5-FU, were analyzed using linear and non-linear Vyazovkin (VYZ) isoconversional methods. The results of the application of these free models on the present kinetic data showed quite dependency of the activation energy on the extent of conversion. The results confirm the complexity of the decomposition of 5-FU and more than one reaction mechanism are involved in the process. In the low conversion range of fraction decomposed , the decomposition is best described by diffusion model, D3. At higher values of decomposition, the nucleation mechanism, A4, gave the best fits to the experimental data. The decomposition path was investigated by intrinsic reaction coordinate (IRC) at the B3LYP/6-311++G(d, p) level of DFT. Two transition states were involved in the process by hemolytic rupture of Nâ�?�?H bond and ring secession, respectively.

Biography :

Email: rmhfouz@science.au.edu.eg