Novel quinoline derivatives as antitumor agents against HepG2 cells: Synthesis, characterization, in silico, in vitro and docking studies

A Simple Methoxyquinoline-Based Ratiometric Fluorescent Probe for Specific Detection of Hydrogen Peroxide in Living Cells and Zebrafish

A simple methoxyquinoline-based ratiometric fluorescent probe was synthesized for detecting hydrogen peroxide (H2O2). After the probe reacted with H2O2, 6-methoxyquinoline fluorescence dye was released, and the fluorescence intensity increased at 366 nm and decreased at 450 nm. And the fluorescence ratio of the probe at 366 and 450 nm is linearly related to the concentration of H2O2 in the range of 0-100 μM; it shows a good ratiometric fluorescence signal. In addition, the probe has good characteristics such as rapid response speed and high sensitivity and selectivity. This fluorescent probe with low biotoxicity and excellent cell membrane permeability was further used to image H2O2 in HeLa cells and zebrafish.

Novel Catalyst-Free Synthesis of Some 3-Alkylaminoquinoxaline-2(1H)-thiones and 3-Alkyloxyquinoxaline-2(1H)-thiones in Ethanol

Seventeen 3-alkylaminoquinoxaline-2(1H)-thiones and 3-alkyloxyquinoxaline-2(1H)-thiones were prepared by a novel thionation protocol from the readily available quinoxaline-2,3-dione in excellent overall yields. This protocol starts with the chlorination of dione using thionyl chloride to give 2,3-dichloroquinoxaline followed by the reaction with equimolar amounts of N-nucleophiles (primary amines and secondary amines) or O-nucleophiles (phenols and alcohols) to principally afford 2-alkanamino-3-chloroquinoxalines or 2-alkyloxy-3-chloroquinoxalines, respectively. The chloroquinoxalines reacted with the thionation reagent N-cyclohexyl dithiocarbamate cyclohexyl ammonium salt in ethanol under reflux to principally give the corresponding quinoxalin-2-yl cyclohexylcarbamodithioate that finally rearranges in situ to give the corresponding thiones in 76-93% overall yields. Our novel catalyst-free synthesis of some 3-alkylaminoquinoxaline-2(1H)-thiones and 3-alkyloxyquinoxaline-2(1H)-thiones in ethanol protocol has many advantages compared with traditional methods: excellent yields, one-pot reaction, simple experimental procedure, and commercial availability of the required reagents. In addition, this method could be generalized to involve a wide range of amines, phenols, and alcohols, and also during the reaction, we did not notice a bad odor. The structures of synthesized compounds are elucidated via different methods such as 1H NMR, 13C NMR, elemental analysis, and MS.

Transformation of Amides to Thioamides Using an Efficient and Novel Thiating Reagent

A convenient protocol was developed for the transformation of N-aryl-substituted benzamides to N-aryl-substituted benzothioamides using N-isopropyldithiocarbamate isopropyl ammonium salt as a novel thiating reagent. The major advantages of this protocol are its one-pot procedure, short reaction times, mild conditions, simple work-up, high yields and pure products.