Diabetes is a serious, long-term (or chronic) disease that occurs when a person’s blood sugar levels are high because their body cannot produce enough insulin, or does not produce enough insulin or that it cannot eff...Diabetes is a serious, long-term (or chronic) disease that occurs when a person’s blood sugar levels are high because their body cannot produce enough insulin, or does not produce enough insulin or that it cannot effectively use the insulin it produces. According to the literature, this disease has several causes, but certain types of diabetes such as type 2 diabetes are most closely linked to a metabolic disorder due to abdominal obesity. Thus, the number of individuals with type 2 diabetes is increasing. It is with this in mind that we work to improve human health. The aim of this study is to design new derivatives of 1,3,4-thiadiazole with improved antidiabetic activity by the mathematical model of multiple linear regression (MLR) established previously. The analysis of the effect on the substituents influencing the antidiabetic activity, fourteen (14) new molecules coded CDTH were generated and presenting values of the potential of inhibitory concentration higher than that of the base compound (pIC50 = 2.526). But thirteen (13) of these new compounds belong to the domain of applicability of the MLR model established previously. In addition, the thermodynamic quantities of formation formed at 298K have been calculated. Lipinski’s rule and pharmacokinetic properties proved that five (5) (TH4, TH9, TH10, TH13 and TH14) new molecules can be used as diabetes medicine.展开更多
This work was carried out on a series of twenty-two (22) benzimidazole derivatives with inhibitory activities against Mycobacterium tuberculosis H37Rv by applying the Quantitative Structure-Activity Relationship (QSAR...This work was carried out on a series of twenty-two (22) benzimidazole derivatives with inhibitory activities against Mycobacterium tuberculosis H37Rv by applying the Quantitative Structure-Activity Relationship (QSAR) method. The molecules were optimized at the level DFT/B3LYP/6-31 + G (d, p), to obtain the molecular descriptors. We used three statistical learning tools namely, the linear multiple regression (LMR) method, the nonlinear regression (NLMR) and the artificial neural network (ANN) method. These methods allowed us to obtain three (3) quantitative models from the quantum descriptors that are, chemical potential (μ), polarizability (α), bond length l (C = N), and lipophilicity. These models showed good statistical performance. Among these, the ANN has a significantly better predictive ability R<sup>2</sup> = 0.9995;RMSE = 0.0149;F = 31879.0548. The external validation tests verify all the criteria of Tropsha et al. and Roy et al. Also, the internal validation tests show that the model has a very satisfactory internal predictive character and can be considered as robust. Moreover, the applicability range of this model determined from the levers shows that a prediction of the pMIC of the new benzimidazole derivatives is acceptable when its lever value is lower than 1.展开更多
For this work, we have selected two reactions for the formation of (2,2)-dichloro (ethyl) Arylphosphine and bis (2,2)-dichloro(ethyl)arylphosphine compounds by hydrophosphination. Global and local reactivity parameter...For this work, we have selected two reactions for the formation of (2,2)-dichloro (ethyl) Arylphosphine and bis (2,2)-dichloro(ethyl)arylphosphine compounds by hydrophosphination. Global and local reactivity parameters, thermodynamic parameters of reactions, Transition states, the Fukui function, the local softness, the local electrophility index, and nucleophility index, Natural population analyses (NPA) and Mulliken (MK) were calculated with DFT method at B3LYP/6-311+G(d, p) level. The analysis of potential energy surfaces and the nature of the reaction mechanism have been determined. The various results obtained revealed that the addition of Arylphosphine is regiospecific. The phenylphosphine is more stable than the thiophenylphosphine. The theoretical results are consistent with experience.展开更多
In this work, we conducted a QSAR study on 18 molecules using descriptors from the Density Functional Theory (DFT) in order to predict the inhibitory activity of hydroxamic acids on histone deacetylase 7. This study i...In this work, we conducted a QSAR study on 18 molecules using descriptors from the Density Functional Theory (DFT) in order to predict the inhibitory activity of hydroxamic acids on histone deacetylase 7. This study is performed using the principal component analysis (PCA) method, the Ascendant Hierarchical Classification (AHC), the linear multiple regression method (LMR) and the nonlinear multiple regression (NLMR). DFT calculations were performed to obtain information on the structure and information on the properties on a series of hydroxamic acids compounds studied. Multivariate statistical analysis yielded two quantitative models (model MLR and model MNLR) with the quantum descriptors: electronic affinity (AE), vibration frequency of the OH bond (ν(OH)) and that of the NH bond (ν(NH)). The LMR model gives statistically significant results and shows a good predictability R2 = 0.9659, S = 0.488, F = 85 and p-value . Electronic affinity is the priority descriptor in predicting the activity of HDAC7 inhibitors in this study. The results obtained suggest that the descriptors derived from the DFT could be useful to predict the activity of histone deacetylase 7 inhibitors. These models were evaluated according to the criteria of Tropsha et al.展开更多
This theoretical chemical reactivity study was conducted using the Density Functional Theory (DFT) method, at computational level B3LYP/6-31G (d). It involved a series of six (06) 5-arylidene rhodanines and allowed to...This theoretical chemical reactivity study was conducted using the Density Functional Theory (DFT) method, at computational level B3LYP/6-31G (d). It involved a series of six (06) 5-arylidene rhodanines and allowed to predict the chemical reactivity of these compounds. DFT global chemical reactivity descriptors (HOMO and LUMO energies, chemical hardness, softness, electronegativity) were examined to predict the relative stability and reactivity of rhodanin derivatives. Thus, the compound 6 which has an energy gap between the orbitals of ΔEgap = 3.004 eV is the most polarizable, the most reactive, the least stable, the best electron donor and the softest molecule. Calculation of the local indices of reactivity as well as dual descriptors revealed that the sulfur heteroatom of the Rhodanine ring is the privileged site of electrophilic attack in a state of sp3 hybridization and privileged site of nucleophilic attack in a state of sp2 hybridization.展开更多
In this work, we have focused our investigations on the protonation sites predilection in the benzimidazolyl- chalcones (BZC) derivatives. Particularly, we are interested in the study of geometrical and energetical pa...In this work, we have focused our investigations on the protonation sites predilection in the benzimidazolyl- chalcones (BZC) derivatives. Particularly, we are interested in the study of geometrical and energetical parameters. BZC are well known for their particularly nematicidal activity. Ten (10) BZC derivatives coded BZC-1 to BZC-10, with various larvicidal concentrations, have been selected for this work. They all are different one from another by the phenyl ring which is substituted by electron modulators such as alkyl, hydroxyl, alkoxy, aminoalkyl, halogen and nitro or replaced by the furan. Quantum chemical methods, namely HF/6-311 + G(d,p) and MPW1PW91/6- 311 + G(d,p) theory levels have been used to determine the geometrical and energetical parameters by the protonation on each heteroatom of the BZC derivative. An accuracy results with relatively less time consuming has been obtained using Hartree-Fock (HF) and Density Functional Theory methods (DFT/MPW1PW91). The calculations results allow identifying the sp<sup>2</sup> nitrogen as the preferential site of protonation in BZC derivative compounds.展开更多
Hydrogen bonding (HB) sites in three pyrimidine compounds derivatives (DP), namely 4-(4-fluorophenyl)-6-(furan-2-yl) pyrimidin-2-amine (DP-1), 4-(4-chlorophenyl)-6-(furan-2-yl) pyrimidin-2-amine (DP-2) and 4-(4-bromop...Hydrogen bonding (HB) sites in three pyrimidine compounds derivatives (DP), namely 4-(4-fluorophenyl)-6-(furan-2-yl) pyrimidin-2-amine (DP-1), 4-(4-chlorophenyl)-6-(furan-2-yl) pyrimidin-2-amine (DP-2) and 4-(4-bromophenyl)-6-(furan-2-yl) pyrimidin-2-amine (DP-3), have been investigated by quantum chemistry methods, especially at HF/6-311+G(d,p) and B3PW91/6-311+G(d,p) levels. Hydrogenfluori deserved as probe for hydrogen bonding complexes. Molecular electrostatic potential maps, geometricparameters of HB complexes, as well as energetic parameters of the complexation reactions have been computed. Finally, one out of two nitrogen atoms of pyrimidine nucleus has been identified as the major hydrogen bonding site in the three pyrimidine derivatives, with respective percentages of around 83.0% and 93.2% at HF/6-311+G(d,p) and B3PW91/6-311+G(d,p) levels.展开更多
Mycolactone molecules are responsible of Buruli ulcer disease. In this work, we are interested in the geometric, energetic and spectroscopic characterization of the hydrogen bonding interactions in mycolactone A/B, us...Mycolactone molecules are responsible of Buruli ulcer disease. In this work, we are interested in the geometric, energetic and spectroscopic characterization of the hydrogen bonding interactions in mycolactone A/B, using quantum chemical method, especially ONIOM(HF/6-311+G(d,p):AM1) and ONIOM (B3LYP/6-311+G(d,p):AM1) levels. ONIOM two layers method has been used because mycolactones compounds are very large, taking into account diffuse and polarization functions are important whenever the matter is intermolecular interactions. Geometric, energetic and spectroscopic parameters of hydrogen bonding reaction on each of the nine oxygen heteroatoms of mycolactone A/B have revealed that the O5sp2 heteroatom is far away the hydrogen bonding site. The identification of such a site constitutes a tool for working out a methodology for the annihilation of the destruction effects of mycolactones.展开更多
文摘Diabetes is a serious, long-term (or chronic) disease that occurs when a person’s blood sugar levels are high because their body cannot produce enough insulin, or does not produce enough insulin or that it cannot effectively use the insulin it produces. According to the literature, this disease has several causes, but certain types of diabetes such as type 2 diabetes are most closely linked to a metabolic disorder due to abdominal obesity. Thus, the number of individuals with type 2 diabetes is increasing. It is with this in mind that we work to improve human health. The aim of this study is to design new derivatives of 1,3,4-thiadiazole with improved antidiabetic activity by the mathematical model of multiple linear regression (MLR) established previously. The analysis of the effect on the substituents influencing the antidiabetic activity, fourteen (14) new molecules coded CDTH were generated and presenting values of the potential of inhibitory concentration higher than that of the base compound (pIC50 = 2.526). But thirteen (13) of these new compounds belong to the domain of applicability of the MLR model established previously. In addition, the thermodynamic quantities of formation formed at 298K have been calculated. Lipinski’s rule and pharmacokinetic properties proved that five (5) (TH4, TH9, TH10, TH13 and TH14) new molecules can be used as diabetes medicine.
文摘This work was carried out on a series of twenty-two (22) benzimidazole derivatives with inhibitory activities against Mycobacterium tuberculosis H37Rv by applying the Quantitative Structure-Activity Relationship (QSAR) method. The molecules were optimized at the level DFT/B3LYP/6-31 + G (d, p), to obtain the molecular descriptors. We used three statistical learning tools namely, the linear multiple regression (LMR) method, the nonlinear regression (NLMR) and the artificial neural network (ANN) method. These methods allowed us to obtain three (3) quantitative models from the quantum descriptors that are, chemical potential (μ), polarizability (α), bond length l (C = N), and lipophilicity. These models showed good statistical performance. Among these, the ANN has a significantly better predictive ability R<sup>2</sup> = 0.9995;RMSE = 0.0149;F = 31879.0548. The external validation tests verify all the criteria of Tropsha et al. and Roy et al. Also, the internal validation tests show that the model has a very satisfactory internal predictive character and can be considered as robust. Moreover, the applicability range of this model determined from the levers shows that a prediction of the pMIC of the new benzimidazole derivatives is acceptable when its lever value is lower than 1.
文摘For this work, we have selected two reactions for the formation of (2,2)-dichloro (ethyl) Arylphosphine and bis (2,2)-dichloro(ethyl)arylphosphine compounds by hydrophosphination. Global and local reactivity parameters, thermodynamic parameters of reactions, Transition states, the Fukui function, the local softness, the local electrophility index, and nucleophility index, Natural population analyses (NPA) and Mulliken (MK) were calculated with DFT method at B3LYP/6-311+G(d, p) level. The analysis of potential energy surfaces and the nature of the reaction mechanism have been determined. The various results obtained revealed that the addition of Arylphosphine is regiospecific. The phenylphosphine is more stable than the thiophenylphosphine. The theoretical results are consistent with experience.
文摘In this work, we conducted a QSAR study on 18 molecules using descriptors from the Density Functional Theory (DFT) in order to predict the inhibitory activity of hydroxamic acids on histone deacetylase 7. This study is performed using the principal component analysis (PCA) method, the Ascendant Hierarchical Classification (AHC), the linear multiple regression method (LMR) and the nonlinear multiple regression (NLMR). DFT calculations were performed to obtain information on the structure and information on the properties on a series of hydroxamic acids compounds studied. Multivariate statistical analysis yielded two quantitative models (model MLR and model MNLR) with the quantum descriptors: electronic affinity (AE), vibration frequency of the OH bond (ν(OH)) and that of the NH bond (ν(NH)). The LMR model gives statistically significant results and shows a good predictability R2 = 0.9659, S = 0.488, F = 85 and p-value . Electronic affinity is the priority descriptor in predicting the activity of HDAC7 inhibitors in this study. The results obtained suggest that the descriptors derived from the DFT could be useful to predict the activity of histone deacetylase 7 inhibitors. These models were evaluated according to the criteria of Tropsha et al.
文摘This theoretical chemical reactivity study was conducted using the Density Functional Theory (DFT) method, at computational level B3LYP/6-31G (d). It involved a series of six (06) 5-arylidene rhodanines and allowed to predict the chemical reactivity of these compounds. DFT global chemical reactivity descriptors (HOMO and LUMO energies, chemical hardness, softness, electronegativity) were examined to predict the relative stability and reactivity of rhodanin derivatives. Thus, the compound 6 which has an energy gap between the orbitals of ΔEgap = 3.004 eV is the most polarizable, the most reactive, the least stable, the best electron donor and the softest molecule. Calculation of the local indices of reactivity as well as dual descriptors revealed that the sulfur heteroatom of the Rhodanine ring is the privileged site of electrophilic attack in a state of sp3 hybridization and privileged site of nucleophilic attack in a state of sp2 hybridization.
文摘In this work, we have focused our investigations on the protonation sites predilection in the benzimidazolyl- chalcones (BZC) derivatives. Particularly, we are interested in the study of geometrical and energetical parameters. BZC are well known for their particularly nematicidal activity. Ten (10) BZC derivatives coded BZC-1 to BZC-10, with various larvicidal concentrations, have been selected for this work. They all are different one from another by the phenyl ring which is substituted by electron modulators such as alkyl, hydroxyl, alkoxy, aminoalkyl, halogen and nitro or replaced by the furan. Quantum chemical methods, namely HF/6-311 + G(d,p) and MPW1PW91/6- 311 + G(d,p) theory levels have been used to determine the geometrical and energetical parameters by the protonation on each heteroatom of the BZC derivative. An accuracy results with relatively less time consuming has been obtained using Hartree-Fock (HF) and Density Functional Theory methods (DFT/MPW1PW91). The calculations results allow identifying the sp<sup>2</sup> nitrogen as the preferential site of protonation in BZC derivative compounds.
文摘Hydrogen bonding (HB) sites in three pyrimidine compounds derivatives (DP), namely 4-(4-fluorophenyl)-6-(furan-2-yl) pyrimidin-2-amine (DP-1), 4-(4-chlorophenyl)-6-(furan-2-yl) pyrimidin-2-amine (DP-2) and 4-(4-bromophenyl)-6-(furan-2-yl) pyrimidin-2-amine (DP-3), have been investigated by quantum chemistry methods, especially at HF/6-311+G(d,p) and B3PW91/6-311+G(d,p) levels. Hydrogenfluori deserved as probe for hydrogen bonding complexes. Molecular electrostatic potential maps, geometricparameters of HB complexes, as well as energetic parameters of the complexation reactions have been computed. Finally, one out of two nitrogen atoms of pyrimidine nucleus has been identified as the major hydrogen bonding site in the three pyrimidine derivatives, with respective percentages of around 83.0% and 93.2% at HF/6-311+G(d,p) and B3PW91/6-311+G(d,p) levels.
文摘Mycolactone molecules are responsible of Buruli ulcer disease. In this work, we are interested in the geometric, energetic and spectroscopic characterization of the hydrogen bonding interactions in mycolactone A/B, using quantum chemical method, especially ONIOM(HF/6-311+G(d,p):AM1) and ONIOM (B3LYP/6-311+G(d,p):AM1) levels. ONIOM two layers method has been used because mycolactones compounds are very large, taking into account diffuse and polarization functions are important whenever the matter is intermolecular interactions. Geometric, energetic and spectroscopic parameters of hydrogen bonding reaction on each of the nine oxygen heteroatoms of mycolactone A/B have revealed that the O5sp2 heteroatom is far away the hydrogen bonding site. The identification of such a site constitutes a tool for working out a methodology for the annihilation of the destruction effects of mycolactones.
