N,N‐Diethyl‐2,6,6‐trimethyl‐4‐(3‐nitrophenyl)‐5‐oxo‐1,4,5,6,7,8‐hexahydroquinoline‐3‐carboxamide

The title compound, C₂₃H₂₉N₃O₄, has potential calcium modulatory properties. The conformation of the 1,4‐di­hydro­pyridine ring is unusual in that it is planar, instead of the usual shallow boat. The 3‐nitro­phenyl substituent is in the synperiplanar orientation with respect to the di­hydro­pyridine ring plane. The oxo­cyclo­hexene ring has a distorted envelope conformation, with the out‐of‐plane atom being disordered on opposite sides of the ring plane. The mol­ecules are linked into chains by intermolecular hydrogen bonds.     

A new Approach for the Voltammetric Sensing of the Phytoestrogen Genistein at a Non-modified Boron-doped Diamond Electrode

An effective electrochemical sensor was constructed using an unmodified boron-doped diamond electrode for determination of genistein by square-wave voltammetry. Cyclic voltammetric investigations of genistein with HClO₄ solution indicated that irreversible behavior, adsorption-controlled and well-defined two oxidation peaks at about +0.92 (P_A1) & +1.27 V (P_A2). pH, as well as supporting electrolytes, are important in genistein oxidations. Quantification analyses of genistein were conducted using its two oxidation peaks. Using optimized experiments as well as instrumental conditions, the current response with genistein was proportionately linear in the concentrations range of 0.1 to 50.0 μg mL⁻¹ (3.7×10⁻⁷−1.9×10⁻⁴ mol L⁻¹), by the detection limit of 0.023 μg mL⁻¹ (8.5×10⁻⁸ mol L⁻¹) for P_A1 and 0.028 μg mL⁻¹ (1.1×10⁻⁷ mol L⁻¹) for P_A2 in 0.1 mol L⁻¹ HClO₄ solution (in the open circuit condition at 30 s accumulation time). Ultimately, the developed method was effectively applied to detect genistein in model human urine samples by using its second oxidation peak (P_A2).     

Inhibitor design for 3-hydroxy-3-methyl-glutaryl-CoA reductase enzyme; molecular docking and determination of molecular and electronic properties of ligands by density functional theory method

Designing new inhibitors having less side effects is a need which also could reduce cholesterol levels. To fulfill this aim, we have carried out a molecular docking study toward 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase. A set of designed structural derivatives of statin drugs, eight ligands which are used as HIV-1 integrase inhibitor candidates, a set of terpenoids, and ligands downloaded from Zinc15 database were docked to HMG-CoA reductase enzyme which contains atorvastatin in crystal structure. The analysis of docking studies revealed that statin derivative ligands are more appropriate for inhibition of HMG-CoA reductase. To define the contribution of the molecular properties to the binding of ligands to enzyme structure; the highest occupied molecular orbitals-lowest unoccupied molecular orbitals, hardness, electronegativity, and chemical potential properties of ligands have best score in their sets calculated by quantum mechanical tools.     

Methyl 4‐(2‐chloro‐5‐nitro­phenyl)‐2,7,7‐tri­methyl‐5‐oxo‐1,4,5,6,7,8‐hexa­hydro­quinoline‐3‐carboxyl­ate

The title compound, C₂₀H₂₁ClN₂O₅, has potential calcium modulatory properties. The 1,4‐di­hydro­pyridine ring has the usual shallow boat conformation. The 2‐chloro‐5‐nitro­phenyl ring is oriented such that the chloro substituent is in a synperiplanar orientation with respect to the 1,4‐di­hydro­pyridine ring plane, while the nitro substituent sits over the 1,4‐di­hydro­pyridine ring. The cyclo­hexenone ring has a conformation that is approximately half‐way between that of an envelope and that of a half‐chair. The mol­ecules are linked into chains by intermolecular N—H⋯O hydrogen bonds.     

()‐9‐(2‐Bromophenyl)‐7,7‐dimethyl‐1,3,4,5,6,7,8,9‐octahydrofuro[3,4‐b]quinoline‐1,8‐dione

The title compound, C₁₉H₁₈BrNO₃, has potential calcium modulatory properties. The 1,4‐di­hydro­pyridine ring has a very shallow boat conformation and is one of the most planar examples of this moiety. The 2‐bromo­phenyl substituent is in the axial synperiplanar orientation. The quinoline ring has a half‐chair conformation, with the unusual arrangement of the out‐of‐plane atom being on the opposite side of the ring plane to the bromo­phenyl substituent. The mol­ecules are linked into chains by intermolecular hydrogen bonds.     

Cocrystals of diastereoisomers of 1,4‐dihydro­pyridine derivatives

A mixture of the RR/SS and RS/SR diastereoisomeric pairs of methyl 4‐(2,4‐dichloro­phen­yl)‐2,7‐dimethyl‐5‐oxo‐1,4,5,6,7,8‐hexa­hydro­quinoline‐3‐carboxyl­ate, C₁₉H₁₉Cl₂NO₃, forms cocrystals in which there is one unique mol­ecule in the asymmetric unit, but the mol­ecule displays disorder in the region of the 7‐position of the quinoline ring system as a result of the random occurrence of the diastereoisomers at the same crystallographic site. A similar arrangement exists in the monohydrate cocrystals that form from a mixture of the RR/SS and RS/SR diastereoisomeric pairs of methyl 4‐(2,4‐dichloro­phen­yl)‐2‐methyl‐7‐phenyl‐5‐oxo‐1,4,5,6,7,8‐hexa­hydro­quinoline‐3‐carboxyl­ate monohydrate, C₂₄H₂₁Cl₂NO₃·H₂O. These compounds belong to a class of 1,4‐dihydro­pyridines whose members have calcium modulatory properties. The 1,4‐dihydro­pyridine rings have the usual shallow boat conformation. In each structure, the 2,4‐dichloro­phenyl ring is oriented such that the 2‐chloro substituent is in a synperi­planar orientation with respect to the 1,4‐dihydro­pyridine ring plane. In each crystal structure, the mol­ecules are linked into chains by N—H⋯O hydrogen‐bonding inter­actions.     

Correlation equations for optimum design of annular fins with temperature dependent thermal conductivity

Correlation equations for optimum design of annular fins with temperature-dependent thermal conductivity are obtained in the present work. The nonlinear fin equation which is associated with variable thermal conductivity condition is solved by Adomian decomposition method that provides an analytical solution in the form of an infinite power series. The optimum radii ratio of an annular fin which maximizes the heat transfer rate has been found as a function of Biot number and the fin volume for a given thermal conductivity parameter describing the variation of the thermal conductivity. The fin volume is fixed to obtain the dimensionless geometrical parameters of the fin with maximum heat transfer rate. The data from the present solutions is correlated for a suitable range of Biot number and the fin volume. The simple correlation equations presented in this work can assist for thermal design engineers for optimum design of annular fins with temperature-dependent thermal conductivity.