A Developed QSPR Model for the Melting Points of Isatin Derivatives

Authors : Rabah KHALİL, Shayma\`a H ABDULRAHMAN

Pages : 1-8

Doi:10.33435/tcandtc.894168

View : 15 | Download : 6

Publication Date : 2022-06-15

Article Type : Other Papers

Abstract :This paper suggests a developed quantitative structure property relationship insert ignore into journalissuearticles values(QSPR); model for coping the melting point insert ignore into journalissuearticles values(M.P); which is considered as the main and important physical property of solid state. The development was based on the decreasing in number of descriptors in order to be statistically intensive with excellent values of statistical parameters. The model was applied successfully to the already published data of M.P for 32 biologically active molecules derived from 4-insert ignore into journalissuearticles values(1-aryl-2-oxo-1,2-dihydro-indol-3-ylideneamino);-N-substituted benzene sulfonamides. The calculations of descriptors were carried out using density functional theory insert ignore into journalissuearticles values(DFT); with bases set of 6-311G insert ignore into journalissuearticles values(d, P);. A statistically intensive QSPR model contains only three descriptors with physical meaning has been introduced. Two of them are belonging to the direct theoretical calculations but the third was considered as three dimensional correcting term of which depending on the chemical structure of the substituent. The theoretically calculated descriptors were the total connectivity insert ignore into journalissuearticles values(TC); and the average charge on the aryl group insert ignore into journalissuearticles values(AQArH); as both depending on the packing of molecules and responsible on M.P. The last descriptor was suggested as a correction term with respect to the packing of molecules of which depending on their three dimensional chemical structure which only taking the values of -1, 0 and 1. A relatively excellent statistical parameters for the developed model were obtained with square regression coefficient insert ignore into journalissuearticles values(r2);, cross-validation insert ignore into journalissuearticles values(q2); and root mean squared error insert ignore into journalissuearticles values(RMSE); are equal to 0.925, 0.903 and 15.26oC, respectively. It was concluded that the developed model gives more confidence results in addition to physical significance which can be considered as a helpful tool for understanding the factors affecting the melting point.
Keywords : QSPR, computational chemistry, isatin derivatives, melting point, DFT