Novel mono substituted pyridoimidazoisoquinoliniums a silver-catalyzed intramolecular cyclization and their applications in cellular imaging.

Cationic heterocycles, an important class of organic compounds soluble in polar solvents, have been gaining attention in the construction of fluorescent probes. This paper reports the quick synthesis of novel pyrido[1',2';2,3]imidazo[5,1-]isoquinoliniums starting from 2-(2-ethynylphenyl)imidazo[1,2-]pyridines at room temperature intramolecular cyclization by employing a catalytic amount of silver trifluoromethanesulfonate in addition to lithium trifluoromethanesulfonate and silica gel as the counter anion source and additive, respectively. The designed pyridoimidazoisoquinoliniums consisted of an imidazo[1,2-]pyridine fused isoquinolinium.

Visualization of the photodegradation of a therapeutic drug by chemometric-assisted fluorescence spectroscopy.

The fluorescence spectral fingerprint, also known as the excitation-emission matrix (EEM), is used to assess and visualize therapeutic drug photodegradation in combination with chemometrics. Examination of EEM-parallel factor analysis (PARAFAC) data showed that an individual component was easily separated from a mixture of photogenerated products of a heterocyclic pharmacophore, in this case, phenothiazine drugs (PTZs). Detailed investigations of both structure-EEM relationships and kinetics revealed that the components extracted from EEM-PARAFAC could be quantitatively attributed to such photogenerated products as phenothiazine sulfoxide and carbazole derivatives.

Silver-catalyzed three-component reaction of uracils, arylboronic acids, and selenium: synthesis of 5-arylselanyluracils.

Herein, we describe a simple and general multi-component synthesis of 5-arylselanyluracils by the regioselective C-H selenation of uracils. Reactions of uracils with arylboronic acid and Se powder in the presence of AgNO (10 mol%) at 120 °C under aerobic conditions afforded various 5-arylselanyluracils. The source of the introduced selanyl group was prepared from a commercially available arylboronic acid and Se powder in the reaction system, thereby ensuring a simple and efficient protocol.

Involvement of PorK, a component of the type IX secretion system, in Prevotella melaninogenica pathogenicity.

Prevotella melaninogenica is a gram-negative anaerobic commensal bacterium that resides in the human oral cavity and is isolated as a pathogen of suppurative diseases both inside and outside the mouth. However, little is known about the pathogenic factors of P. melaninogenica.

Novel fimbrilin PGN_1808 in Porphyromonas gingivalis.

Porphyromonas gingivalis, a periodontopathic gram-negative anaerobic bacterium, generally expresses two types of fimbriae, FimA and Mfa1. However, a novel potential fimbrilin, PGN_1808, in P. gingivalis strain ATCC 33277 was recently identified by an in silico structural homology search.