Impact of Geometric Parameters,Charge, and Lipophilicity on Bioactivity of Armed Quinoxaline,Benzothiaole, and Benzothiazine: Pom Analyses of Antibacterial and Antifungal Activity

Abstract

A series of four different armed heterocyclic candidates; 1-(2-methyl-2,3-dihydro-1,3-benzothiazol-2-yl)acetone (2), 1-(3-methyl-4H-1,4-benzothiazin-2-yl)ethanone (3), 2-[(2-aminophenyl)dithio]aniline (4), and 3-hydroxy-3-methyl-4-(3-methyl-2-quinoxalinyl)-2-butanone (5) have been prepared and their microbial activities were evaluated. A correlation of the structure and activities relationships of these compounds with respect to molecular modeling, Lipinski Rule of Five, drug likeness, toxicity profiles, and other physico-chemical properties of drugs are described and verified experimentally.     

Studies on 2-Aminothiophenes: Synthesis,Transformations, and Biological Evaluation of Functionally-Substituted Thiophenes and Their Fused Derivatives

Abstract

Heterocyclic enamines1 reacted with ethyl acetoacetate to afford the corresponding amide derivatives2. Treatment of2 with carbon disulphide yielded the dipotassium salts3which reacted in-situ with a variety of α -haloketones to give the respective substituted thiophenes5,8, and13. The reactivity of the latter products towards various chemical reagents was studied to yield their fused thiophene derivatives7,10,12, and14, respectively. Some representative compounds were tested for antimicrobial activity.     

Synthesis and pesticidal activities of novel anthranilic diamides containing pyridylpyrazole and iminodithiocarbamate or thiosemicarbazone motifs

Abstract

A series of novel anthranilic diamide derivatives containing pyridylpyrazole and iminodithiocarbamate or thiosemicarbazone motifs were synthesized via multi-step reactions. The structures of seven title compounds (methyl 2-(2-(3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamido)-5-chloro-3- methylbenzylidene)hydrazinecarbodithioate 7 and 3-bromo-N-(2-((2-substitutedcarbamothioylhydrazono)methyl)-4-chloro-6-methylphenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide 8a-8f) were confirmed by melting points, IR, ¹H NMR, ¹³C NMR, and HRMS. The bioassays showed that some of the compounds exhibited modest insecticidal activities against oriental armyworm (Mythimna separata Walker), particularly, compound 8b (3-bromo-N-(4-chloro-2-methyl-6-((2-(methylcarbamothioyl)hydrazono)methyl)phenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide) held 100% and 30% larvicidal activity at the concentration of 25?mg/L and 10?mg/L, respectively. In addition, several compounds displayed favorable fungicidal activities against Alternaria solani Sorauer and Physalospora piricola at 50?μg/mL, and were comparable with the controls Chlorothalonil and Triadimefon. The results in this paper will provide important information for further research and development of sulfur-containing heterocyclic agrochemicals.     

Preparation and solution properties of a novel cationic hydrophobically modified polyacrylamide for enhanced oil recovery

Abstract

A novel cationic water-soluble monomer allyldimethylisooctylammonium bromide (ADIAB) containing a short-chain alkane was synthesized successfully. This monomer was copolymerized with acrylamide and sodium acrylate to produce hydrophobically modified polyacrylamide (HMPAM) using solution polymerization without surfactants. The structures of monomer ADIAB and HMPAM were characterized with infrared spectroscopy and nuclear magnetic resonance spectroscopy. Influence of preparation condition on viscosities of products was studied. The aqueous solution viscosity of the terpolymer was also investigated as functions of concentration, temperature and salinity. The results showed that when the temperature exceeds the 60?°C and NaCl concentration exceeds about 2000?mg/L, the temperature and salt tolerance characters of terpolymer were demonstrated. The enhanced oil recovery tests were initially carried out using homogeneous sandpack models.     

Antifungal activity of silver nanoparticle-encapsulated β-cyclodextrin against human opportunistic pathogens

Silver nanoparticles were synthesised by reducing silver acetate with a long-chain aliphatic amine. β-Cyclodextrin (CD)-stabilised silver nanoparticles were successfully synthesised and characterised by the UV–vis spectroscopy and scanning electron microscopy analysis. This system was examined for their antifungal activity against opportunistic human pathogens such as Aspergillus fumigatus, Mucor ramosissimus and Chrysosporium species. This study clearly demonstrates that the present system is a powerful antifungal agent against human opportunistic pathogenic fungi.     

On‐line process monitoring of coffee roasting by resonant laser ionisation time‐of‐flight mass spectrometry: bridging the gap from industrial batch roasting to flavour formation inside an individual coffee bean

Resonance‐enhanced multiphoton ionisation time‐of‐flight mass spectrometry (REMPI‐TOFMS) enables the fast and sensitive on‐line monitoring of volatile organic compounds (VOC) formed during coffee roasting. On the one hand, REMPI‐TOFMS was applied to monitor roasting gases of an industrial roaster (1500 kg/h capacity), with the aim of determining the roast degree in real‐time from the transient chemical signature of VOCs. On the other hand, a previously developed μ‐probe sampling device was used to analyse roasting gases from individual coffee beans. The aim was to explore fundamental processes at the individual bean level and link these to phenomena at the batch level. The pioneering single‐bean experiments were conducted in two configurations: (1) VOCs formed inside a bean were sampled in situ, i.e. via a drilled μ‐hole, from the interior, using a μ‐probe (inside). (2) VOCs were sampled on‐line in close vicinity of a single coffee bean's surface (outside). The focus was on VOCs originating from hydrolysis and pyrolytic degradation of chlorogenic acids, like feruloyl quinic acid and caffeoyl quinic acid. The single bean experiments revealed interesting phenomena. First, differences in time–intensity profiles between inside versus outside (time shift of maximum) were observed and tentatively linked to the permeability of the bean's cell walls material. Second, sharp bursts of some VOCs were observed, while others did exhibit smooth release curves. It is believed that these reflect a direct observation of bean popping during roasting. Finally, discrimination between Coffea arabica and Coffea canephora was demonstrated based on high‐mass volatile markers, exclusively present in spectra of Coffea arabica. Copyright © 2013 John Wiley & Sons, Ltd.     

Solanopubamine,a rare steroidal alkaloid from Solanum schimperianum: Synthesis of some new alkyl and acyl derivatives,their anticancer and antimicrobial evaluation

Solanopubamine (3β-amino-5α, 22αH, 25βH-solanidan-23β-ol), a steroidal alkaloid was isolated from the alkaloidal fraction of Solanum schimperianum in significant yield. Its structure was established by IR, positive ESI-MS, 1D and 2D NMR. The presence of -3β-NH₂ and -23β-OH groups was achieved through methylation, acetylation or coupling with octadecanoic and undec-11-enoic acids to produce six derivatives (2–7). Their structures were confirmed by spectroscopic analyses. Solanopubamine and semi-synthetic analogs are investigated for their in vitro cytotoxicity against a panel of human cancer cell lines and anti-microbial activity. Solanopubamine showed good antifungal activity only against Candida albicans and C. tenuis with MIC of 12.5 μg/mL. Semi-synthesized compounds (2–7) have failed to show anti-tumor and anti-microbial activities.     

Asymmetric Synthesis, Antifungal Activity and Molecular Modeling of Iodiconazole Isomers

Iodiconazole is a novel antifungal agent that was developed in its racemic form. In order to investigate the ef- fects of the chiral center on the antifungal activity, R- and S-isomers of iodiconazole were prepared on the basis of the asymmetric Sharpless epoxidation. （S）-Iodiconazole was proved to have better antifungal activity than the （R）- isomer. The binding modes of the two isomers with lanosterol 14~z-demethylase were clarified by molecular dock- ing.     

Synthesis and in vitro biological evaluation of novel 2-aminoimidazolone derivatives as anti-tumor agents

Novel 2-aminoimidazolone derivatives were synthesized.Most compounds displayed strong anticancer activities against human carcinoma cells in vitro.Compounds 8a,8b and 8j exhibited optimal activity superior to 5-FU in most cancer cells tested.Especially,the lC₅₀s of 8b（12.6-21.5μmol/L） against five tumor cells were 1 -4 fold less than those of 5-FU（18.4-56.1μmol/L） in vitro.Furthermore,comp以ound 8b could induce SMMC-7721 cell apoptosis in a dose-dependent manner.Therefore,our novel findings may provide a new framework for the design of new 2-aminoimidazolone derivatives for the treatment of cancer.