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Quantitative structure activity relationship studies were applied on a series of 22 molecules of thiazolidine-2,4-dione. The compounds used are potent inhibitors of the 15-hydroxyprostaglandin dehydrogenase (15-PGDH). The present study was performed using multiple regression analysis (MLR) and artificial neural network (ANN) to predict a QSAR model using molecular descriptors. Our results suggest QSAR model based of the following descriptors: polarizability (Pol), molar volume (MV), hydration energy (HE), surface area grid (SAG), molar weight (MW), energy of frontier orbital's EHOMO (The Highest Occupied Molecular Orbital) and ELUMO (The Lowest Unoccupied Molecular Orbital) and atomic net charges (qN3, qC4, qC5 and qO7) for the inhibitory activities of 15-hydroxyprostaglandin dehydrogenase. The best predictive models by MLR and ANN methods gave highly significant square correlation coefficient (R2) values of 0.9623 and 0.9963 respectively. The model also exhibited good predictive power confirmed by the high value of R2 pred (0.7839 and 0.6324 respectively). [ABSTRACT FROM AUTHOR]

The photophysical properties (absorption, fluorescence and phosphorescence) of a series of triarylboranes of the form 4‐D−C6H4−B(Ar)2 (D=tBu or NPh2; Ar=mesityl (Mes) or 2,4,6‐tris(trifluoromethylphenyl (Fmes)) were analyzed theoretically using state‐of‐the‐art DFT and TD‐DFT methods. Simulated emission spectra and computed decay rate constants are in very good agreement with the experimental data. Unrestricted electronic computations including vibronic contributions explain the unusual optical behavior of 4‐tBu−C6H4−B(Fmes)22, which shows both fluorescence and phosphorescence at nearly identical energies (at 77 K in a frozen glass). Analysis of the main normal modes responsible for the phosphorescence vibrational fine structure indicates that the bulky tert‐butyl group tethered to the phenyl ring is strongly involved. Interestingly, in THF solvent, the computed energies of the singlet and triplet excited states are very similar for compound 2 only, which may explain why 2 shows phosphorescence in contrast to the other members of the series. [ABSTRACT FROM AUTHOR]