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The multiple electronic state mechanisms of the reaction of carboryne with benzene were investigated by M11 calculations. Mechanisms leading to [412] cycloaddition product P412, [212] cycloaddition product P212, C-C insert product PC-Cins and CAH insert product PC-Hins were considered. The barrier/stability to structural characteristics correlations revealed that, 1) [212] addition is a two-step mechanism which exhibits three electronic state reactivity, and both the addition steps are controlled by the barriers on open-shell singlet (OSS) potential energy surface (PES); 2) [4+2] product P412 is a kinetic product on the experimental condition, and other products should be obtained under more harsher condition. The theoretical results well explain the experimental facts. [ABSTRACT FROM AUTHOR]

The Diels–Alder (DA) covalent dimerization mechanisms of pyridine were studied at the MP2/6-311G(d,p) level. Involvement of N atom in DA reaction causes high barrier height, otherwise the barrier heights are low. The two most stable D I dimers formed by intermolecular DA reaction ( b-γ D I and b-γ′ D I ) and the two most stable D II dimers formed by further intramolecular DA reaction ( c-γ D II and c-γ′ D II ) were located with relative energy of 26.6 and 26.1 kcal/mol, and 32.1 and 31.6 kcal/mol, respectively, higher than two moles of pyridines. Theoretical results suggested that DA dimerization of pyridine is slightly easier than that of benzene. [ABSTRACT FROM AUTHOR]

The article focuses on the study which examines the influence of β-hydroxybutyrate (BHBA) on the apoptosis of hepatocytes in a primary cultured bovine. Among the techniques that were used in the study are hepatocytes treatment, fluorescence microscopy, and real-time fluorescence quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Results show that enzyme activity of P38 has increased in a concentration-dependent manner.

Abstract: The potential function theory for plane elasticity of three-dimensional icosahedral quasicrystals has been developed, huge numbers of complicated equations involving the elasticity are reduced to a single partial differential equation, fundamental solution of the equation is expressed in six analytic functions of complex variable. [Copyright &y& Elsevier]

In the title compound, C(26)H(18)N(4)O(6), the amide units are approximately coplanar with the benzene ring bonded to the N atom [dihedral angles of 10.59 (10) and 24.00 (12)°], but twisted significantly out of the plane of the benzene ring bonded to the carbonyl C atom [dihedral angles of 57.82 (9) and 58.05 (9)°]. The dihedral angle between the two rings of the biphenyl unit is 77.66 (4)°. Intra-molecular N-H⋯O hydrogen bonds and weak C-H⋯O inter-actions occur. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds and C-H⋯O contacts.

In the title compound, C(28)H(24)N(2)O(4), the dihedral angle between the two rings of the biphenyl unit is 75.34 (9)°. The outer aromatic rings form dihedral angles of 66.96 (1) and 85.69 (8)° with the rings to which they are attached . The mol-ecular structure is stabilized by intra-molecular C-H⋯O and N-H⋯O hydrogen bonds. In the crystal structure, inter-molecular N-H⋯O inter-actions are observed.

The cation of the title compound, C(36)H(34)N(6)O(2) (2+)·2PF(6) (-), lies across a crystallographic inversion centre. The imidazole and pyridine rings form dihedral angles of 82.28 (5)° and 11.87 (7)°, respectively, with the anthracene ring system. The crystal packing is stabilized by π-π inter-actions between the pyridine ring and the central ring of anthracene, with a ring centroid-centroid distance of 3.684 (3) Å. The PF(6) (-) anion is disordered over three different positions with occupancies of 0.284 (6), 0.354 (8) and 0.362 (9).