A simplified coronary model for diagnosis of ischemia-causing coronary stenosis.

BACKGROUND AND OBJECTIVE: The functional assessment of the severity of coronary stenosis from coronary computed tomography angiography (CCTA)-derived fractional flow reserve (FFR) has recently attracted interest. However, existing algorithms run at high computational cost. Therefore, this study proposes a fast calculation method of FFR for the diagnosis of ischemia-causing coronary stenosis. METHODS: We combined CCTA and machine learning to develop a simplified single-vessel coronary model for rapid calculation of FFR. First, a zero-dimensional model of single-vessel coronary was established based on CCTA, and microcirculation resistance was determined through the relationship between coronary pressure and flow. In addition, a coronary stenosis model based on machine learning was introduced to determine stenosis resistance. Computational FFR (cFFR) was then obtained by combining the zero-dimensional model and the stenosis model with inlet boundary conditions for resting (cFFRr) and hyperemic (cFFRh) aortic pressure, respectively. We retrospectively analyzed 75 patients who underwent clinically invasive FFR (iFFR), and verified the model accuracy by comparison of cFFR with iFFR. RESULTS: The average computing time of cFFR was less than 2 s. The correlations between cFFRr and cFFRh with iFFR were r = 0.89 (p < 0.001) and r = 0.90 (p < 0.001), respectively. Diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio for cFFRr and cFFRh were 90.7%, 95.0%, 89.1%, 76.0%, 98.0%, 8.7, 0.1 and 92.0%, 95.0%, 90.9%, 79.2%, 98.0%, 10.5, 0.1, respectively. CONCLUSIONS: The proposed model enables rapid prediction of cFFR and exhibits high diagnostic performance in selected patient cohorts. The model thus provides an accurate and time-efficient computational tool to detect ischemia-causing stenosis and assist with clinical decision-making.

An Active Catalyst System Based on Pd (0) and a Phosphine-Based Bulky Ligand for the Synthesis of Thiophene-Containing Conjugated Polymers.

To address the limitations of conventional Pd catalysts in the polymerization of thiophene-containing conjugated polymers, an active catalyst system based on Pd (0) and a phosphine-based bulky ligand, L1, is explored systematically in Suzuki-Miyaura polymerizations using thiophene boronic acid pinacol ester as one of the monomers. This active catalyst is found very efficient in synthesizing a series of thiophene-containing linear and hyperbranched conjugated polymers. First, as a model example, coupling reactions between electron-rich/moderately hindered aryl or thienyl halides and thiophene boronic acid pinacol ester give excellent yields with lower catalyst loading and can be completed in a shorter reaction time relative to Pd(PPh3)4. Notably, high molecular weight thiophene-containing polymers are successfully synthesized by Suzuki-Miyaura polycondensation of 2,5-thiophene bis(boronic acid) derivatives with different dibromo- and triple bromo-substituted aromatics in 5-15 min.

Cu3N nanowire array as a high-efficiency and durable electrocatalyst for oxygen evolution reaction.

Developing non-precious oxygen evolution reaction (OER) electrocatalysts with high performance and long-term stability has drawn considerable research interest in recent years. In this communication, we report a self-supported Cu3N nanowire array on copper foam (Cu3N NA/CF) which is derived from a Cu(OH)2 nanowire array on copper foam (Cu(OH)2 NA/CF) through a nitridation process. Intriguingly, this 3D electrode exhibits marvellous OER activity with the need of an overpotential of only 298 mV at a current density of 20 mA cm-2 in 1.0 M KOH. In addition, the obtained electrocatalyst is capable of maintaining its high performance for at least 25 h under a static current density of 20 mA cm-2.

Synthesis, crystal structure, spectra and quantum chemical study on 1-phenyl-3-(4-nitrophenyl)-5-(2-thienyl)-2-pyrazoline.

1-Phenyl-3-(4-nitrophenyl)-5-(2-thienyl)-2-pyrazoline was synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. UV-Vis spectra and fluorescence spectra were measured. Density functional theory calculations on the structure of the title compound were performed at the B3LYP/6-311G** level of theory. NPA atomic charge distributions indicate that, although the S atom in the thienyl ring loses coordination capacity, the title compound still may be used as a potential multi-dentate ligand to coordinate with metallic ions. The calculation of the second order optical nonlinearity was carried out. Natural bond orbital analyses indicate that the electronic absorption bands are mainly derived from the contribution of n→π* and π→π* transitions. Fluorescence spectra determination shows that the title compound is a potential orange-light emitting material.

Inhibition mechanism exploration of quinoline derivatives as PDE10A inhibitors by in silico analysis.

As a potential target for the treatment of schizophrenia, the dual cAMP/cGMP hydrolyzing enzyme PDE10A has attracted a significant amount of attention. In the present work, the inhibition mechanism of 116 structurally diverse quinoline derivatives as PDE10A inhibitors was explored by 3D-QSAR, molecular docking and molecular dynamics (MD) simulations. The QSAR models based on the training set containing 88 molecules were established by using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). The resultant optimum CoMSIA model showed strong predictability with a Q(2) of 0.497, an R(ncv)(2) of 0.964 and an R(pre)(2) of 0.885. Furthermore, there was good consistency between the CoMSIA model, docking and MD results. Our findings are: (1) bulky substituents at the 8-position and ring D increase the biological activity. (2) The areas around the 14-position and ring D are the electrostatic and hydrophobic sensitive regions. (3) H-bonds, π-π stacking interactions and hydrophobic contacts are crucial in determining the binding affinity to PDE10A. (4) The six-membered heterocyclic group at ring D, especially a heterobenzene ring, containing the atom as an H-bond acceptor at the 18-position is essential to water-mediated H-bond networks and favorable in enhancing the inhibitory potency. These models and the derived information may help to provide better understanding of the interaction mechanism of PDE10A inhibitors and to facilitate lead optimization and novel inhibitors' design.

5-tert-Butyl 3-ethyl 1-isopropyl-4,5,6,7-tetra-hydro-1H-pyrazolo-[4,3-c]pyridine-3,5-dicarboxyl-ate.

In the title compound, C(17)H(27)N(3)O(4), the six-membered ring adopts a half-chair conformation with the N atom and the adjacent methyl-ene C atom displaced by -0.391 (2) and 0.358 (2) Å, respectively, from the plane of the other four atoms. In the crystal, mol-ecules are linked by weak C-H⋯O inter-actions.

N-Cyclo-propyl-N-[2-(2,4-difluoro-phen-yl)-2-hy-droxy-1-(1H-1,2,4-triazol-1-yl)prop-yl]-2-(5-methyl-2,4-dioxo-1,2,3,4-tetra-hydro-pyrimidin-1-yl)acetamide dichloro-methane 0.62-solvate.

In the title compound, C(21)H(22)F(2)N(6)O(4)·0.62CH(2)Cl(2), the difluoro-substituted benzene ring forms dihedral angles of 54.6 (3)° with the mean plane of the thymine ring and 50.9 (2)° with the triazole ring. The dihedral angle between the thymine and triazole rings is 7.4 (3)°. In the crystal, inter-molecular N-H⋯N and O-H⋯O hydrogen bonds link the main mol-ecules into chains along [10[Formula: see text]]. The CH(2)Cl(2) solvent mol-ecule was refined as partial occupancy over two sets of sites with refined occupancies of 0.308 (9) and 0.310 (8).

7-Benzyl-2,7-diaza-spiro-[4.4]nonan-1-one.

In the title compound, C(14)H(18)N(2)O, both the spiro-linked five-membered rings adopt envelope conformations, with a C atom as the flap in one ring and an N atom in the other. The dihedral angle between the two four-atom planes is 80.46 (8)°. In the crystal, the mol-ecules are linked by N-H⋯O hydrogen bonds to generate C(4) chains propagating in [010].

(3S,12R,20S,24R)-20,24-Ep-oxy-dammarane-3,12,25-triol.

In the title mol-ecule, C(30)H(52)O(4), the three six-membered rings are in chair conformations, the cyclo-pentane ring is in an envelope form and the tetra-hydro-furan ring has a conformation inter-mediate between half-chair and sofa. In the crystal, mol-ecules are linked by inter-molecular O-H⋯O hydrogen bonds into helical chains along [100]. Two intra-molecular O-H⋯O hydrogen bonds are also present. One C atom of the tetrahydrofuran ring and its attached H atoms are equally disordered over two sets of sites.

6-Benzyl 4-ethyl 2-chloro-5,6,7,8-tetra-hydro-pyrido[4,3-d]pyrimidine-4,6-di-carboxyl-ate.

In the title compound, C(18)H(18)ClN(3)O(4), the dihedral angle between the pyrimidine ring and the N-bonded ester grouping is 56.27 (7)° and the dihedral angle between the aromatic rings is 11.23 (7)°.

(3R,6R,12R,20S,24R)-20,24-Ep-oxy-dammarane-3,6,12,25-tetra-ol.

In the title compound, C(30)H(52)O(5), the three six-membered rings are in chair conformations, the five-membered ring is in an envelope form and the tetra-hydro-furan ring has a conformation inter-mediate between half-chair and sofa. Intra-molecular O-H⋯O hydrogen bonds may influence the conformation of the mol-ecule. In the crystal, mol-ecules are linked by inter-molecular O-H⋯O hydrogen bonds, forming a three-dimensional network.

Synthesis, characterization, crystal structure and DFT studies on 3-(1H-benzo[d][1,2,3]triazol-1-yl)-1-(4-ethylphenyl)-1-oxopropan-2-yl-4-ethylbenzoate.

3-(1H-benzo[d][1,2,3]triazol-1-yl)-1-(4-ethylphenyl)-1-oxopropan-2-yl-4-ethyl-benzoate (BEOE) has been synthesized and characterized by elemental analysis, IR, UV-vis and fluorescence spectroscopy. Its crystal structure has also been determined by X-ray single crystal diffraction. For the title compound, density functional theory (DFT) calculations of the structure and vibrational frequencies have been performed at B3LYP/6-31G* level of theory. Based on the vibration analysis, thermodynamic properties of the title compound have been calculated. The correlative equations between the thermodynamic properties and temperatures have also been listed. By using TD-DFT method, electron spectra of the title compound have been predicted, which suggests the B3LYP/6-31G* method can approximately simulate the electron spectra for the system presented here.

Tetra-imidazole-bis(trichloro-acetato)copper(II).

The title compound, [Cu(C(2)Cl(3)O(2))(2)(C(3)H(4)N(2))(4)], was prepared by the reaction of imidazole and trichloro-acetatocopper(II). The Cu(II) atom adopts a distorted octa-hedral coordination geometry, binding the N atoms of four imidazole ligands and the carboxyl-ate O atoms of two trichloro-acetate anions. The mol-ecular structure and packing are stabilized by N-H⋯O hydrogen-bonding inter-actions. Close inter-molecular Cl⋯Cl contacts [3.498 (3) Å] are also found in the structure.

2,7-Dibromo-9,9-bis-[(pyridin-1-ium-4-yl)meth-yl]fluorene dinitrate.

In the title compound, C(25)H(20)Br(2)N(2) (2+)·2NO(3) (-), the cation lies on a twofold rotation axis which imposes disorder of the dibromo-fluorene unit. In addition, the unique nitrate anion is disordered over two general sites of equal occupancy. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds.

1-[3-(2-Nitro-phen-yl)-5-phenyl-2-pyrazolin-1-yl]ethanone.

The title compound, C(17)H(15)N(3)O(3), was prepared from 1-(2-nitro-phen-yl)-3-phenyl-prop-2-en-1-one and hydrazine. The dihedral angle between the benzene and phenyl rings is 74.55 (2)°. The pyrazoline ring is in a slight envelope conformation with the C atom bonded to the phenyl ring forming the flap. In the crystal structure, weak inter-molecular C-H⋯O hydrogen bonds connect mol-ecules into chains along [100].

(3R,6R,12R,20S,24S)-3,6,12-Triacetyl-20,24-ep-oxy-dammarane-3,6,12,25-tetra-ol.

The title compound, C(36)H(58)O(8), was prepared from 20(S)-protopanaxatriol, which was degraded from Panax quinquefolium saponin with sodium in glycerine, extracted and seperated by flash chromatography. Three six-membered rings are in chair conformations, the five-membered ring is in an envelope form and the tetra-hydro-furan ring has a conformation inter-mediate between half-chair and envelope. In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds, and C-H⋯O contacts also occur. The absolute structure was assigned on the basis of the synthesis.

N'-[1-(4-Chloro-phen-yl)ethyl-idene]acetohydrazide.

In the title compound, C(10)H(11)ClN(2)O, the dihedral angle between the acetohydrazide group and the aromatic ring is 33.76 (9)°. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate R(2) (2)(8) loops.

N'-(4-Fluoro-benzyl-idene)acetohydrazide.

The title compound, C(9)H(9)FN(2)O, was prepared by the reaction of 4-fluoro-benzophenone and acethydrazide. In the mol-ecule, all non-H atoms are essentially coplanar [r.m.s. deviation = 0.065 (2) Å]. In the crystal, mol-ecules are linked into centrosymmetric dimers by pairs of inter-molecular N-H⋯O hydrogen bonds.

(3R,6R,12R,20S,24S)-20,24-Ep-oxy-dammarane-3,6,12,25-tetraol dihydrate.

The title compound, C(30)H(52)O(5)·2H(2)O, was degraded from pseudoginsenoside F11 which was extracted and seperated from Panax quinquefolium saponin. The three six-membered rings are in chair conformations. The five-membered ring is in an envelope conformation and the tetra-hydro-furan ring has a conformation inter-mediate between half-chair and envelope. In the crystal, inter-molecular O-H⋯O hydrogen bonds link mol-ecules into a three-dimensional network. Intra-molecular O-H⋯O hydrogen bonds also occur.

Experimental and theoretical comparative studies on two 2-pyrazoline derivatives.

Two 2-pyrazoline derivatives of 1-phenyl-3-(4-methylphenyl)-5-phenyl-2-pyrazoline (1) and 1-phenyl-3-(4-methylphenyl)-5-(2,4-dichlorophenyl)-2-pyrazoline (2) have been synthesized and characterized by elemental analysis, IR, UV-vis and fluorescence spectroscopy. The crystal structure of 2 has been determined by X-ray single crystal diffraction. For the two compounds, density functional theory (DFT) calculations of the structures and natural population atomic charge analysis have been performed at B3LYP/6-311G** level of theory. By using TD-DFT method, electron spectra of 1 and 2 have been predicted, which suggests the B3LYP/6-311G** method can approximately simulate the electron spectra for the system presented here. Comparative studies on 1 and 2 indicate that the change of substituent in 5-phenyl ring of pyrazoline ring influences the peak location and intensity in electronic and fluorescence spectra.