Synthesis of 1-aryl-3H-[1,2,5]triazepino[5,4-a]benzimidazol-4(5H)-ones and quantum chemical investigation of the rotamers of the Boc-protected hydrazide key intermediate

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Label-free immunosensor for monitoring vitellogenin as a biomarker for exogenous oestrogen compounds in amphibian species

A label-free, optical waveguide lightmode spectroscopy based immunosensor was developed for frog (Bombina orientalis) vitellogenin (Vtg) determination in biological samples as a biomarker for exogenous oestrogen compounds. Antibody against Vtg was produced in rabbits immunised with purified lipovitellin (Lpv), a precursor of Vtg, from the homogenised ovary of oriental fire-bellied toads (B. orientalis). The purified protein and Lpv/Vtg-specific serum were applied in both competitive and direct immunoassay formats using optical waveguide lightmode spectroscopy immunosensor. When measuring Vtg in direct manner, the Lpv antibody (1.76 µg mL^?1) was immobilised on the sensor surface, and the linear measuring range for Vtg was 0.1–10 µg mL^?1. During the competitive measurement, 100 ng mL^?1 Lpv was applied for the immobilisation. The linear measuring range for Vtg was 0.5–50 ng mL^?1. We studied the relative substrate specificity of the antibody, and it was concluded that the method is suitable for the sensitive and selective determination of Vtg levels in toads. Heart, liver and gonad samples from male animals were spiked with Vtg and were analysed using the newly developed method, and female toads and spawn samples were tested and compared to the calibration curve obtained by the spiked samples.     

Metal‐Chelating N,N′‐Bis(4‐dimethylaminophenyl)acetamidinyl Radical: A New Chromophore for the Near‐Infrared Region

A new non‐innocent ligand redox system, N,N′‐bis(4‐dimethylaminophenyl) substituted acetamidinato/acetamidinyl, has been designed and described by example of structurally and spectroscopically characterized ruthenium complexes. The hitherto unreported ligand is responsible for rather intense and narrow absorptions in the near‐infrared region of the one‐ and two‐electron oxidized forms. The spectroscopic, computational, and first structural characterization of an amidinyl radical complex adds to the list of established N‐based radical ligands.     

Determination of the specific heat using laser flash apparatus

Journal of Thermal Analysis and Calorimetry - The main aim of this article was to describe the methodology for the measurement of specific heat using the laser flash apparatus. The obtained values...     

Direct Catalytic Enantio‐ and Diastereoselective Ketone Aldol Reactions of Isocyanoacetates

A catalytic asymmetric aldol addition/cyclization reaction of unactivated ketones with isocyanoacetate pronucleophiles has been developed. A quinine‐derived aminophosphine precatalyst and silver oxide were found to be an effective binary catalyst system and promoted the reaction to afford chiral oxazolines possessing a fully substituted stereocenter with good diastereoselectivities and excellent enantioselectivities.