Synthesis and in vitro antimicrobial screening of new pyrano[4,3-b]pyrane derivatives of 1H-pyrazole

A new series of pyrano[4,3-b]pyrane 4a-l bearing 1H-pyrazole has been synthesized by one pot base catalyzed cyclocondensation reaction of 1H-pyrazole-4-carbaldehyde la-1,malononitrile 2 and 4-hydroxy-6-methylpyrone 3.All the synthesized compounds were screened against six bacterial pathogens,namely B.subtilis,C.tetani,S.pneumoniae,S.typhi,V.cholerae, E.coli and antifungal activity against,two fungal pathogens,A.fumigatus and C.albicans using broth microdilution MIC method. Some of the compounds are found to be equipotent or more potent than that of commercial drugs,against most of employed strains.     

Synthesis and antimicrobial screening of pyrano[3,2-<Emphasis Type="Italic">c</Emphasis>]chromene derivatives of 1<Emphasis Type="Italic">H</Emphasis>-pyrazoles

A new series of twenty four derivatives of pyrano[3,2-c]chromene IVa-x bearing 1H-pyrazole were synthesized by a one pot, base-catalyzed cyclocondensation reaction of 1H-pyrazole-4-carbaldehyde Ia-l, malononitrile II and 4-hydroxycoumarin IIIa-b. All the synthesized compounds were characterized by elemental analysis, FT-IR, ¹H NMR and ¹³C NMR spectral data. All the synthesized compounds were screened against six bacterial pathogens, namely B. subtilis, C. tetani, S. pneumoniae, S. typhi, V. cholerae, E. coli and for antifungal activity against two fungal pathogens, A. fumigatus and C. albicans using the broth microdilution MIC method. Some of the compounds were found to be equipotent or more potent than commercial drugs against most of employed strains, as evident from the screening data.      

Evaluation and solubility improvement of Carvedilol: PSC[n]arene inclusion complexes with acute oral toxicity studies

The aqua phobic molecules that are practically insoluble in aqueous media demonstrate a staggeringly slow intrinsic dissolution rate. In this work, we exemplify the utility of calixarenes as a tool to form inclusion complexes with Carvedilol (CDL). It is poorly water soluble drug. CDL is a Biopharmaceutical Classification System (BCS) Class II drug and it is a nonselective β-adrenegenic blocking agent with α1-blocking activity. It is mainly used in the management of hypertension. The maximum complexation of the drug was accomplished after 48?h of stirring with para sulphonato calix[4]arene (PSC[4]arene) and para sulphonato calix[6]arene (PSC[6]arene) in water and evaporation of water to acquire solid complexes. The study includes characterisation of both the complexes—physical mixtures of drug and PSC[4]arene and PSC[6]arenes by different methods like Fourier-transform infra red spectroscopy, differential scanning calorimetry and powder X-ray diffraction, proton nuclear magnetic resonance. This studies shows that there is electrostatic interaction between drug and PSC[n]arenes. The complexation was determined by phase solubility study. The prepared complexes exhibited improved in vitro dissolution profile and decreased in vivo acute oral toxicity compared to the pure drug.     

Au@SiO2 core-shell nanoparticles for laser desorption/ionization time of flight mass spectrometry

In matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), the analysis capability, especially for small molecules, is often compromised by the addition of organic matrices due to the existence of background signals. Herein we report a new detection method on the utility of core-shell nanoparticles (CSNPs) as energy transfer structure in LDI-TOF-MS. The LDI-TOF-MS based on gold-silica core-shell nanoparticles with ultrathin silica shell of 2-4 nm (Au@utSiO(2) CSNPs) was effectively applied to the analysis of many compounds, especially for small functional molecules and polymers, which was more promising than MALDI-TOF-MS.     

Synthesis and characterization of reactive dyes based on 2-phenyl-3-[4′-(4″-aminophenylsulphonamido)]phenyl-4(3H)-quinazolinone-6-sulphonic acid

A series of new quinazolinone based mono azo reactive dyes (D_1–10) have been prepared by subsequent diazotization of 2-phenyl-3-[4′-(4″-aminophenylsulphonamido)]phenyl-4(3H)-quinazolinone-6-sulphonic acid (C) and coupling with various 4-chloro anilino cyanurated coupling components. These dyes give purple, red, orange and yellow color shades. All the reactive dyes were characterized by their percentage yield, UV–Vis spectroscopy, elemental analysis, IR spectroscopy, ¹H NMR spectroscopy and dyeing performance on silk, wool and cotton fibres. The percentage dye bath exhaustion on different fibres has been found to be reasonably good and acceptable. The dyed fibres show moderate to very good light fastness and good to excellent washing and rubbing fastness.     

Molecular iodine catalyzed synthesis of tetrazolo[1,5-a]-quinoline based imidazoles as a new class of antimicrobial and antituberculosis agents

A series of some new tetrazolo[1,5-a]quinoline based tetrasubstituted imidazole derivatives 6a-1 have been synthesized by a reaction of tetrazolo[1,5-a]quinoline-4-carbaldehyde 3a-d,benzil 4,aromatic amine 5a-c and ammonium acetate in the presence of iodine through one-pot multi-component reaction(MCR) approach.All the derivatives were screened for antimicrobial and antituberculosis activities and results worth further investigations.     

Microwave assisted synthesis of novel Hantzsch 1,4-dihydropyridines, acridine-1,8-diones and polyhydroquinolines bearing the tetrazolo[1,5-a]quinoline moiety and their antimicrobial activity assess

Microwave assisted efficient Hantzsch reaction via four-component coupling reactions of tetrazolo[1,5-α]quinoline-4-carbal-dehyde, dimedone/cyclohexane-1,3-dione,ethyl/methyl acetoacetate and ammonium acetate was described as the preparation of tetrazolo[1,5-α]quinoline based 1,4-dihydropyridines,acridine-1,8-diones and polyhydroquinolines.The process presented here is simple,rapid,environmentally welcoming and high yielding.All the derivatives were subjected to an in vitro antimicrobial screening against a representative panel of bacteria and fungi and results worth further investigations.     

Investigation of Physicochemical Properties of Plasma Activated Water and its Bactericidal Efficacy

Plasma Chemistry and Plasma Processing - Presently, the world is using different types of disinfectants for various applications such as disinfecting instrument surfaces in the medical field,...     

An Efficient Synthesis of Novel 2‐(5‐indolyl)‐1H‐benzimidazole Derivatives and Evaluation of Their Antimicrobial Activities

In this paper, we report the synthesis of novel 2‐(5‐indolyl)‐1H‐benzimidazole derivatives. The methodology involves the Sonogashira reaction of 4‐(1H‐benzimidazol‐2‐yl)‐2‐bromo‐N,N‐dimethylaniline ( 3 ) with variety of terminal alkynes to get corresponding novel 4‐(1H‐benzimidazol‐2‐yl)‐2‐alkynyl‐N,N‐dimethylaniline derivatives ( 4 ). These compounds on iodocyclization afforded novel iodoindolylbenzimidazole derivatives ( 5 ). The resulting compounds were functionalized further via palladium‐mediated carbon–carbon bond formation for generating novel structurally diversified heterocyclic compounds. All these newly synthesized compounds were evaluated for antimicrobial activity.     

A Facile Synthesis of Novel Benzofuranyl Benzimidazole Derivatives

In this article, we report a facile route for the synthesis of novel benzofuranyl benzimidazole derivatives. The methodology involves the Sonagashira reaction of 2‐(3‐iodo‐4‐methoxyphenyl)‐1H‐benzimidazole ( 3 ) with variety of terminal alkynes to have novel benzimidazole alkynyl derivatives followed by iodo‐cyclisation to give novel iodo benzofuranyl benzimidazole derivatives. The resulting iodo benzofuranyl benzimidazoles were functionalized further via palladium mediated carbon–carbon bond formation for molecular diversity generating novel heterocyclic compounds.