Die spektrale Abstimmung der Elektrochemilumineszenz (ECL) von Luciferin – grün nach rot wird durch Elektrolyt-Engineering erreicht, was zeigt, dass dafür keine Keto/Enol-Isomerisierung des Emitters erforderlich ist. visuelle Darstellung ECL ermöglicht eine unkomplizierte optische Messung Superoxid-Diffusivität, wie Michelle L. Coote, Marco Garavelli, Simone Ciampi et al. in ihrem Forschungsart...

The study of tautomerics equilibria is vital importance as tautomeric compounds reactivity highly depends on the proportion each tautomer. Herein, equilibrium 3-phenyl-2,4-pentanedione was studied theoretically by b3lyp/6-31+g(d)methods. effect four solvents considered (water, methanol, carbon tetrachloride and Cyclohexane).The takes place through four-membered ring transition state. barrier he...

The aim of this study was to determine the electronic influence of substituent groups and annelated rings such as oxazole-oxazinone on the physicochemical and photoprotection, antioxidant capacity, toxicity and singlet oxygen photosensitization biological properties of isoquinoline alkaloid frameworks. Thus, oxoisoaporphine derivatives 1-5 and 3-azaoxoisoaporphine (6), some of them with phenoli...

A series of new tautomeric azonaphthols are synthesized and the possibilities for molecular switching are investigated using molecular spectroscopy, X-ray analysis and density functional theory quantum chemical calculations. Two opposite effects that influence switching are studied: attaching a piperidine sidearm, and adding substituents to the phenyl ring. On the one hand, the attached piperid...

The kinetics of triplet state quenching of 3,3',4,4'-benzophenone tetracarboxylic acid (BPTC) by DNA bases adenine, adenosine, thymine, and thymidine has been investigated in aqueous solution using time-resolved laser flash photolysis. The observation of the BPTC ketyl radical anion at λ(max) = 630 nm indicates that one electron transfer is involved in the quenching reactions. The pH-dependence...

The structures of l-phenyl-3-methyl-pyrazolone-5 and its benzoyl derivatives have been investigated by means of IR, UV, NMR, and mass spectral spectroscopy. 1-Phenyl 3-methyl-pyrazolone-5 is found to exist as a zwitter ion in the solid state, in the 5-keto form in chloroform and dioxane, and in the 5-hydroxy form in pyridine. The 4-benzoyl derivative of l-phenyl-3-methyl-pyrazolone-5 is shown t...

The potential energy profiles for proton-transfer reactions of 2-hydroxypyridine and its complexes with water were determined by MP2, CASSCF and MR-CI calculations with the 6-31G** basis set. The tautomerization reaction between 2-hydroxypyridine (2HP) and 2-pyridone (2PY) does not take place at room temperature because of a barrier of approximately 35 kcal/mol for the ground-state pathway. The...

In their Review (article number 2001952), Ling Chen, Peng-Yan Fu, Mei Pan and co-workers give a summary introduction of ESIPT (excited state intramolecular proton transfer) materials in the solid including small organic molecules, metal-organic frameworks covalent-organic frameworks. The four-leveled energy cycle based keto-enol emissions these respond to temperature, pressure, solvent, ions, l...

The wobble hypothesis does not discriminate between uracil and thymine. Methylation could favor further stabilization of uracil in the keto form. Thymine is present in keto form only and can pair up but with adenine. Uracil can easily construct the enol form; that is why it forms the U-G pair. In previous E-print I proposed an alternative to the wobble hypothesis [1]. According to my reviewers ...