BACKGROUND Microbial oxidative degradation is a potential way of removing pollutants such as heterocycles from the environment. During this process, reactive oxygen species or other oxidants are inevitably produced, and may cause damage to DNA, proteins, and membranes, thereby decreasing the degradation rate. Carotenoids can serve as membrane-integrated antioxidants, protecting cells from oxida...

The utilization of green chemistry techniques is dramatically reducing chemical waste and reaction times as has recently been proven in several organic syntheses and chemical transformations. To illustrate these advantages in the synthesis of bioactive heterocycles, we have studied various environmentally benign protocols that involve greener alternatives. Microwave (MW) irradiation of neat rea...

Nosocomial infection caused by methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococci (VRE) has become a great deal of recent concern. Although a number of cephalosporins had been synthesized in the past, few of them was effective against these resistant bacteria. Recently, TOC-39and TOC-50^3) bearing vinyl-thio linkage attached by substituted pyridines at C-3 we...

A new class of tricyclic heterocycles 4H-benzo[g][1,2,3]triazolo[5,1-c][1,4]oxazocines was synthesized through a Knoevenagel condensation/azide-alkyne cycloaddition reaction cascade in one-pot operation. These eight membered ring containing heterocycles exhibited moderately high anticancer activity against four cancer cell lines; human cervix cancer cell line (HeLa), human prostate cancer cell ...

Benzotiazole and pyrimidine have been reported to act as effective pharmacophores. However, much less work as been carried out on these heterocycles fused with each other. In the present study, we report the synthesis of a series of 8-chloro-3(phenylcarbonoimidoyl)-10a-H-pyrimido [2,1-b][1,3]benzothiazole-2-thiol. This series was synthesized by the reaction of 8-chloro-2-sulfanyl-10a-H-pyrimido...

Saturated oxygen heterocycles, such as tetrahydrofurans and dihydrobenzofurans, are important motifs in a myriad of biologically active compounds, including natural products and pharmaceutical targets. Therefore, there has been considerable interest in the development of new synthetic methods for the construction of these important structures. Many traditional approaches to the generation of th...

Three 3-hydroxymonoazine- and three N-hydroxydiazine-type heterocycles were tested whether they act as artificial siderophores toward Aureobacterium flavescens JG-9 (ATCC No. 25091). Among them, 1-hydroxy-3,5,6-trimethyl-2(1H)-pyrazinone (3) showed the highest growth-promotion activity comparable to desferrioxamine B (DFB), a natural trihydroxamate siderophore, at 48.5 microM or above, followed...

Novel chromophores based on the alternation of electron-poor (pyridyl) and electron-rich (ethylenedioxythienyl) heterocycles were synthesized for the first time and shown to exhibit attractive optical properties in relation with their specific electronic and geometrical (coiled structure) features.

The first examples of hetero Diels-Alder reaction of masked o-benzoquinones with nitroso dienophiles leading to novel and highly functionalized heterocycles, which are potential intermediates for nitrogenous natural products are reported.