Isoxazolines are an important class of nitrogen and oxygen containing heterocycles that belong to the azoles family which have gained much importance in the field of medicinal chemistry as the ...anticancer agents. Moreover, natural products are always expectedly regarded as an important hoard of a large number of potential chemotherapeutic candidates. Therefore, this review mainly focuses on the existence of isoxazoline derivatives in natural sources, their isolation and uses there of as anticancer agents besides highlighting the synthetic pathways to achieve these compounds. Structural–activity relationship and the influence of stereochemical aspects on anticancer activity of such compounds have also been discussed. It covers the literature upto 2014 and would certainly provide a great insight to scientific community to accelerate further research for the development of some novel anticancer drugs.
Isoxazoline derivatives exhibit a broad spectrum of biological properties. The present review describe the existence of natural isoxazolines as anticancer agents, their isolation and synthetic pathways. Display omitted
•Natural isoxazolines medicinally gained much attention as anticancer agents.•Structural–activity relationship, isolation and synthetic pathways.•Influence of absolute configurations on anticancer potential.•Most of the compounds were cytotoxic against MCF-7 and HCT-116 cell lines.
Candida auris
is a recently described rare agent of fungemia. It is notable for its antifungal resistance. A total of 15
C. auris
isolates, originating from seven cases of fungemia, three cases of ...diabetic gangrenous foot, and one case of bronchopneumonia from a tertiary care hospital in south India, were investigated. All of the 15 isolates were identified by sequencing and 14 of these along with 12
C. auris
isolates previously reported from two hospitals in Delhi, north India, two each from Japan and Korea were genotyped by amplified fragment length polymorphism (AFLP). In vitro antifungal susceptibility testing (AFST) was done by the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method.
Candida auris
isolates were misidentified as
Candida haemulonii
by VITEK. All were resistant to fluconazole geometric mean minimum inhibitory concentration (MIC) 64 μg/ml and 11 isolates were resistant to voriconazole (MIC ≥1 μg/ml). Forty-seven percent of the
C. auris
isolates were resistant to flucytosine (MIC ≥64 μg/ml) and 40 % had high MIC (≥1 μg/ml) of caspofungin. Breakthrough fungemia developed in 28.6 % of patients and therapeutic failure in 4 (66.7 %) patients. Interestingly, the 26 Indian
C. auris
isolates from north and south India were clonal and phenotypically and genotypically distinct from Korean and Japanese isolates. The present study demonstrates that
C. auris
is a potential emerging pathogen that can cause a wide spectrum of human mycotic infections. The prevalence of a
C. auris
endemic clonal strain resistant to azoles and other antifungals in Indian hospitals with high rates of therapeutic failure in cases of fungemia is worrisome.
Since the discovery of Helicobacter pylori(H. pylori) in 1983, numerous detection methods for the presence of the bacterium have been developed. Each one of them has been associated with advantages ...and disadvantages. Noninvasive tests such as serology, 13 C urea breath test(UBT) and stool antigen tests are usually preferred by the clinicians. Serology has its own limitation especially in endemic areas while 13 C UBT is technically very demanding. The stool antigen detection method, although specific, is usually associated with poor sensitivity. The 13 C UBT is believed to be specific, but with present revelation of the fact that stomach is colonized by many other urease producing bacteria makes it questionable. Histology, culture, rapid urease test and polymerase chain reaction(PCR) are the tests which are carried out on antral biopsies collected by invasive means. Histology has been proposed to be very sensitive and specific but the question is how by simply looking the morphology of the bacteria in the microscope, one can claim that the curved bacterium is exclusively H. pylori. Rapid urease test(RUT), the doctor’s test, is also challenged because the presence of other urease producing bacteria in the stomach cannot be denied. Moreover, RUT has been reported with poor sensitivity specially, when density of the bacterium is low. Isolation of H. pylori is essential to investigate its growth requirements, antibiotic susceptibility testing, studying virulence factor to develop vaccine and many more explorations. It has also got several disadvantages i.e., special condition for transporting, media, incubation and few days waiting for the colonies to appear, apart from the speed essentially needed to process the specimens. Till date, majority of the microbiological laboratories in the world are not equipped and trained to isolate such fastidious bacterium. The option left is PCR methods to detect H. pylori ’s DNA in gastric mucosa, gastric juice, saliva, dental plaques and environmental specimens. There are speculations for false positivity due to detection of non-pylori Helicobacters due to genetic sharing; and false negativity due to low bacterial counts and presence of PCR inhibitors. However, specimen collection, transportation and processing do not require speed and special conditions. PCR based diagnosis may be considered as gold standard by designing primers extremely specific to H. pylori and targeting at least more than one conserved genes. Similarly specificity of PCR may be improved by use of internal Primers. Further, nested PCR will take care of false negatives by countering the effect of PCR inhibitors and low bacterial counts. Therefore, nested PCR based methods if performed properly, may be proposed as gold standard test.
•Ni(OH)2 NFAs@ZnO–ZnCo2O4 NWAs and Fe2O3@NF NFAs composite were proposed.•The both active materials were directly grown on nickel foam via hydrothermal approach.•The hierarchical composite structure ...accelerates the ion diffusion and electron transfer.•The electrochemical performances of FHSCs device were constructed.•The novel FHSCs device achieved superhigh energy and power densities.
A preeminent technique to boost the energy density of flexible hybrid supercapacitor (FHSCs) is to develop unique, extremely efficient, and smart positive and negative current collectors with hierarchical nanoarchitectures integration of various electroactive materials. Herein, we present a facile and flexible approach towards the synthesis of selective integration of hierarchical leaflet-like Ni(OH)2 nanoflake arrays with ZnO–ZnCo2O4 nanowire arrays (Ni(OH)2 NFAs@ZnO–ZnCo2O4 NWAs) on Ni foam mesh for ultrahigh-capability electrodes. The innovative strategy results in hierarchical architecture with highly altered electronic nanostructure, which not only enhances the specific surface area but also provides ultrafast transportations between ions and electrons. Under electrochemical conditions, the battery-type materials of the hierarchical leaflet-like Ni(OH)2 NFAs@ZnO–ZnCo2O4 NWAs electrodes show ultrahigh specific capacity of 237.7 mA h g−1 at 2 A g−1; this value is 2.16, 1.53 and 1.30 times than those of ZnO–ZnCo2O4 NWAs, CoO NFAs@ZnO–ZnCo2O4 NWAs and ZnO NFAs@ZnO–ZnCo2O4 NWAs electrodes, respectively. Most importantly, in flexible assembly, the Ni(OH)2 NFAs@ZnO–ZnCo2O4 NWAs//Fe2O3@NF NFAs FHSCs device delivers an ultrahigh energy density of 80.10 W h kg−1 a superior life-spam performance, and retention around 98.2% of initial capacity after 5000 cycles. The new innovative strategy could be very promising for future flexible electronics devices.
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Biomass is a green energy source and is available in abundance. Biochar is a carbon-rich material derived from a wide range of biomass or organic waste through the thermochemical route. Biochar has ...received increasing attention because of its distinctive properties such as high carbon content, greater specific surface area, cation exchange capacity, nutrient retention capacity, and stable structure. This review paper extensively studies and reports the different pyrolysis processes, reactor types, the effect of process parameters on biochar yield, and its physicochemical properties, biochar activation methods, and applications. It also details the status of the research and development (R&D) progress in biochar production through conventional and advanced technologies. The study found that unlike many products (at R&D stage) biochar has high potential to scale up and has a direct impact on crop yield, water purification (for domestic and industrial application), alternative fuels (clean solid fuel for cookstove), air purification, catalyst, biogas production, purification, and storage. In addition, the paper lists the merits and challenges in the novel biochar applications like hydrogen storage, electrochemical capacitor, and fuel cell technology.
Graphic abstract
Water and food security are the key challenges under climate change as both are highly vulnerable to continuously changing climatic patterns. Studies have predicted that the average global ...temperature may increase by 1.4–5.8°C and there would be substantial reduction in fresh water resources and agricultural yield by the end of the 21st century. Approximately 75% of the Himalayan glaciers are on retreat and will disappear by 2035. Moreover in Africa (Sub-Saharan Africa) by 2050 the rainfall could drop by 10%, which would reduce drainage by 17%. Majority of the fresh water resources has already been depleted and there is reduction in agricultural production globally with escalation in population and food demand. Some of the prominent climate change impacts are, growing deserts, and increase in the magnitude of floods and droughts. An extreme decline in crop yields in arid and semi arid areas globally has caused food shortages and a manifold increase in food inflation. Countries of Africa, Middle East, Arab and Asia have close economic ties with natural resource and climate-dependent sectors such as forestry, agriculture, water, and fisheries. This manuscript highlights groundwater recharge by utilization of wastewater using the Soil Aquifer Treatment (SAT) method in irrigation and the significance and methods of artificial recharge of groundwater. This paper also presents easily and economically feasible options to ensure water and food security under climate change and recommend formation of effective adaptation and mitigation polices and strategies to minimizing the impact of climate change on water resources and irrigation.
At ambient pressure, bulk rhombohedral bismuth is a semimetal that remains in the normal state down to at least 10 millikelvin. Superconductivity in bulk bismuth is thought to be unlikely because of ...the extremely low carrier density. We observed bulk superconductivity in pure bismuth single crystals below 0.53 millikelvin at ambient pressure, with an estimated critical magnetic field of 5.2 microteslas at 0 kelvin. Superconductivity in bismuth cannot be explained by the conventional Bardeen-Cooper-Schrieffer theory because its adiabatic approximation does not hold true for bismuth. Future theoretical work will be needed to understand superconductivity in the nonadiabatic limit in systems with low carrier densities and unusual band structures, such as bismuth.
Electrochromic devices (ECDs) are emerging as novel technology for various applications ranging from commercialized smart window glasses, goggles, and autodimming rear view mirrors to uncommon yet ...more sophisticated applications such as infrared camouflage in military and thermal control in space satellites. The development of low-power, lightweight, inexpensive, and flexible devices is the need of the hour. In this respect, utilizing PEDOT:PSS as transparent conducting electrode (TCE) to replace indium tin oxide (ITO) and metal based TCEs for ECDs is a promising solution for the aforementioned requirements. In this work we have demonstrated the performance of PEDOT:PSS films coated on flexible substrates, treated with PTSA-DMSO, as TCEs for ECD applications and their comparison with that of ITO based ECDs. The PEDOT:PSS based flexible TCEs used in this study have conductivity of 1400–1500 S·cm–1 and figure of merit (FoM) of 70–77. The process of increasing the conductivity of PEDOT:PSS films also led to the broadening of the conducting potential window (CPW), which is important for electrochemical applications of PEDOT:PSS when used as a stand-alone electrode. More than achieving a comparable electrochromic contrast, switching time, and coloration efficiency with respect to the ITO based ECDs, PEDOT:PSS devices also had the added advantage of good mechanical flexibility. These devices demonstrated superior stability during electrochemical cycling and multiple mechanical bending tests, making them an inexpensive alternative to the costly ITO based ECD technology.
Herein, we present an interfacial engineering strategy to construct an efficient hydrothermal approach by in situ growing cobalt-doped@MnO2 nanocomposite on highly conductive nickel foam (Ni foam) ...for supercapacitors (SCs). The remarkably high specific surface area of Co dopant provides a larger contacting area for MnO2. In the meantime, the excellent retentions of the hierarchical phase-based pore architecture of the cobalt-doped surface could beneficially condense the electron transportation pathways. In addition, the nickel foam (Ni foam) nanosheets provide charge-transport channels that lead to the outstanding improved electrochemical activities of cobalt-doped@MnO2. The unique cobalt-doped@MnO2 nanocomposite electrode facilitates stable electrochemical architecture, multi-active electrochemical sites, and rapid electro-transports channels; which act as a key factor in enhancing the specific capacitances, stability, and rate capacities. As a result, the cobalt-doped@MnO2 nanocomposite electrode delivered superior electrochemical activities with a specific capacitance of 337.8 F g–1 at 0.5 A g–1; this is greater than pristine MnO2 (277.9 F g–1). The results demonstrate a worthy approach for the designing of high-performance SCs by the grouping of the nanostructured dopant material and metal oxides.
A palladium-catalyzed aminocarbonylation of halo-substituted 7-azaindoles utilizing CHCl
as the carbonyl source has been developed for the straightforward incorporation of an amide functional group. ...The protocol was extended to other heteroarenes such as pyrazolopyridines and indazoles. The substrate scope of the reaction with respect to heteroarenes and the amine component is reported. This method offers an alternative avenue for aminocarbonylation of pharmaceutically important heterocycles.
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