Green Reaction Research Articles

Facile Synthesis of Silicon-Based Materials Modified Using Zinc(Ⅱ) 2-Bromoacetic as Heterogeneous Catalyst for the Fixation of CO2 into Cyclic Carbonates

Much effort has been devoted to the development of efficient heterogeneous catalysts for the conversion of carbon dioxide (CO2) into high-value chemicals. Generally, the cycloaddition of CO2 to epoxides is considered a green and atom-economic reaction for the production of cyclic carbonates. Based on this, three kinds of silicon-based catalysts modified using zinc(Ⅱ) 2-bromoacetic (Si-ZnBA-n, n = 1, 2, 3) were facilely synthesized and employed for the chemical fixation of CO2 to epoxides with the use of potassium iodide (KI). A series of characterization techniques were used to characterize the textual structures and physicochemical properties of Si-ZnBA-n. The synergistic effects of Zn, –NH2, –OH and the nucleophilic group guaranteed the catalytic activity of Si-ZnBA-n. Si-ZnBA-1 exhibited the best catalytic activity among Si-ZnBA-n because Si-ZnBA-1 possessed the highest Zn content. Additionally, the effects of the reaction conditions (temperature, pressure, time and catalyst loadings) were also discussed. The propylene carbonate (PC) yield could reach 97% under 130 °C, 2 MPa, for 5 h without the employment of organic solvent, and its selectivity was 99%. In addition, the recycling property of Si-ZnBA-1/KI was also investigated, and the catalytic system exhibited good cycle performance. Meanwhile, the catalyst showed outstanding versatility for CO2 application to various epoxides, and a possibly synergistic reaction mechanism was proposed. Finally, a dynamic model was developed to discuss the activation energy of the CO2 cycloaddition reaction over the Si-ZnBA-1 catalyst.

Highly selective C3-sulfenylation and C3-selenylation of 3-iodo-5-arylpyrazolo[1,5-a]pyrimidin-7-amine in water

Highly selective C3-sulfenylation and C3-selenylation of 3-iodo-5-aryl pyrazolo[1,5-a]pyrimidin-7-amine in water was established to provide a green and effective method for the construction of diverse C3-aryl sulfide and C3-aryl selenide derivatives. This regioselective C3-sulfenylation and C3-selenylation protocol proceeds efficiently in the presence of phase transfer catalyst PEG-400 with moderate to good yields. The strategy offers the advantages of green reaction conditions, a wide range of substrates, and gram-scale synthesis.

Organo‐Catalytic Approach for Biscoumarin Synthesis via a Biomass‐Derived Sustainable Strategy

AbstractBiscouamrins are dimers of 4‐hydroxycoumarin formed by reaction of aldehydes and 4‐hydroxycoumarin. These were synthesized via one‐pot pseudo three component cascade reaction using sugar ionic liquid as an organo catalyst under green reaction conditions. Sugar derived from natural carbohydrates were used in the formulation of D‐ribose sugar ionic liquid (RSIL). In the formation of biscouamrins two reactions occurs i. e., Knoevenagel condensation and Michael addition reaction. Substituted aliphatic, aromatic and heterocyclic aldehydes were used for the synthesis of a variety of target biscouamrins products and developed protocol is scalable. Substitutions in the aryl ring of benzaldehyde showed very less or no effect on the reaction rate. The developed catalyst was shown to be recyclable five times without losing much of its efficiency.

Recent Developments in Direct C-H Functionalization of Quinoxalin-2(1H)-Ones via Heterogeneous Catalysis Reactions.

In recent years, Web of Science has published nearly one hundred reports per year on quinoxalin-2(1H)-ones, which have attracted great interest due to their wide applications in pharmaceutical and materials fields, especially in recyclable heterogeneous catalytic reactions for direct C-H functionalisation. This review summarises for the first time the methods and reaction mechanisms of heterogeneous catalytic reactions of quinoxalin-2(1H)-ones, including six major types of heterogeneous catalysts involved. The heterogeneous reactions of quinoxalin-2(1H)-ones are summarised by classifying different types of catalytic materials (graphitic phase carbon nitride, MOF, COF, ion exchange resin, piezoelectric materials, and microsphere catalysis). In addition, this review discusses the future development of heterogeneous catalytic reactions of quinoxalin-2(1H)-ones, including the construction of C-B/Si/P/RF/X/Se bonds by heterogeneous catalytic reactions, the enrichment of heterogeneous catalysts such as metal oxides, graphene-based composites, doped metal nanoparticles, and molecular sieve-based porous materials, asymmetric synthesis, and other areas. The aim of this review is to contribute to the development of green and sustainable heterogeneous reaction methods for quinoxalin-2(1H)-ones with applications in materials chemistry and pharmacology.

Nano-Cavities within Nano-Zeolites: The Influencing Factors of the Fabricating Process on Their Catalytic Activities.

Titanium silicalite-1 (TS-1) is a milestone heterogeneous catalyst with single-atom tetrahedral titanium incorporated into silica framework for green oxidation reactions. Although TS-1 catalysts have been industrialized, the strategy of direct hydrothermal synthesis usually produces catalysts with low catalytic activities, which has still puzzled academic and industrial scientists. Post-treatment processes were widely chosen and were proven to be an essential process for the stable production of the high-activity zeolites with hollow structures. However, the reasons why post-treatment processes could improve catalytic activity are still not clear enough. Here, high-performance hollow TS-1 zeolites with nano-sized crystals and nano-sized cavities were synthesized via post-treatment of direct-synthesis nano-sized TS-1 zeolites. The influencing factors of the fabricating processes on their catalytic activities were investigated in detail, including the content of alkali metal ions, the state of titanium centers, hydrophilic/hydrophobic properties, and accessibility of micropores. The post-treatment processes could effectively solve these adverse effects to improve catalytic activity and to stabilize production. These findings contribute to the stable preparation of high-performance TS-1 catalysts in both factories and laboratories.

A novel Schiff-based palladium-complex as a capable nanocatalyst for the green synthesis of hexahydroquinolines and benzochromenes

A novel Schiff-based Pd complex (Fe3O4@SiO2@CPTES@MEL@SAL@Pd) was synthesized by modification of Fe3O4 NPs with tetraethyl orthosilicate (TEOS), 3-chloropropyltriethoxysilane (CPTES), melamine (MEL) and salicylaldehyde (SAL) and further complexation with Pd(II) and characterized by various techniques.Then, the catalytic activity of the Fe3O4-supported Schiff-based Pd complex was studied in the green one-pot multicomponent condensation reactions of: i) the aldehyde, dimedone, ethyl acetoacetate and ammonium acetate (synthesis of hexahydroquinolines) and ii) the aldehyde, malononitrile and 2-hydroxynaphthalene-1,4-dione (synthesis of benzochromenes).

Preparation of isotropic submicron spherical boron nitride particles by restricted template method

AbstractHexagonal boron nitride (h‐BN) has received considerable attention, due to its high thermal conductivity and electrical insulation. However, the intrinsic platelike structure with the strong anisotropic property restricts its applications, and it is necessary to synthesize isotropic spherical h‐BN particles (SP‐BNs) with submicron size. Till now, methods to prepare (SP‐BN) still exist problems, such as high oxygen impurities and pollution, generated by the ammonia and pyrolysis of precursors. Here, a relatively green reaction between the restricted template of carbon nanospheres and boron trioxide (B2O3) under elevated temperature is conducted, and the SP‐BNs with an average diameter of 200–300 nm (named Nano‐BN‐s) have been successfully synthesized. Comprehensive scanning electron microscopy, transmission electron microscopy, and X‐ray diffraction characterizations confirm the obtained products are spherical boron nitride. With the analysis of X‐ray photoelectron spectroscopy and Fourier transform infrared, the reaction mechanism is briefly discussed. These results indicate the reaction occurs on the restricted template of carbon nanospheres, and the C atoms are substituted by B and N atoms as the reaction progress, forming the Nano‐BN‐s. What is more, the restricted template method plays a key role in the design and improves h‐BN‐based materials in the future and may also be extended to form other novel materials.

Capturing primary ozonides for a syn-dihydroxylation of olefins.

Ozonolysis is a widely used and practical synthetic technique for the deconstructive oxidation of olefins using ozone. While there are numerous ozonolysis reactions that give a myriad of products and functionalities, almost all of them involve scission at the olefin double bond. Using ozone as a constructive reagent rather than a deconstructive one would open new domains of chemical reactivity and amplify molecular complexity in synthetic methodology. Here we report the use of primary ozonides as preparative synthetic intermediates for a safe and green olefin syn-dihydroxylation reaction. Furthermore, we have demonstrated this method using a continuous flow reactor that virtually eliminates peroxide accumulation and extended these applications towards the synthesis of pharmaceutically relevant small molecules such as guaifenesin, the active ingredient in Mucinex, and a precursor to ponesimod, a drug to treat multiple sclerosis.

Construction of a new 2D coral-like covalent organic framework as CuI nanoparticles carrier for the preparation of diverse triazoles

In this work, a novel two-dimensional coral-like covalent organic framework (COF) with hydrazone linkages containing pyridine dicarbohydrazide moieties namely PDC-COF was designed and developed through a condensation reaction between the tri(4-formyl phenoxy) cyanurate (TFPC) and 2,6-dimethylpyridine-3,5-dicarbohydrazide (DMPDC) without applying inert atmosphere and using of any acidic catalyst. PDC-COF applied as carrier for CuI nanoparticles for construction of a robust heterogeneous catalyst (PDC-COF/CuI). This catalyst shows high thermal stability (up to 500 °C), good porosity (≃50 m2 g−1), acceptable crystalline structure with coral-like morphology. Accordingly, the obtained data revealed that the synthesized PDC-COF/CuI is highly active heterogeneous catalyst for the preparation of diverse triazoles by using different starting materials under green and mild reaction conditions. In addition, in comparison with the reported data in the literature, all of the prepared compounds have good yields (71–93%) and relatively short reaction times (45 min–15 h). Moreover, PDC-COF/CuI shows excellent stability and reusability (up to 6 times) without any significant decreases in its catalytic performance.

Assessing growth performance and agro-meteorological indices of green gram (Vigna radiata L.) varieties influenced by soil amendments and foliar application under sodic soil in Cauvery delta zone of Tamil Nadu

Green gram prefers neutral soil reactions and is sensitive to saline and alkaline soil conditions. Around 2.1 % of the country's geographical area is salt-affected, of which 3.77 million ha is sodic soil. Rehabilitation of salt-affected soil using drainage is expensive and leaching with good quality water is not feasible. To overcome this, a field experiment was conducted at Anbil Dharmalingam Agricultural College and Research Institute, Tiruchirappalli, during summer 2022 to study the effect of soil amendments and foliar nutrition under sodic soil. The experiment was laid out in a split-plot design with three replications. The treatments comprised of different varieties in main plots (M1, M2, M3, M4, M5 and M6) and different soil amendments with foliar application in sub plots (S1, S2 and S3). The results showed that VBN (Gg) 4 + gypsum @ 50 % GR + pressmud @ 10 t ha-1 + FS of brassinosteroid 0.2 ppm (M4S1) registered higher plant height (18.31, 31.52 & 60.63 cm), DMP (907, 1932 & 2969 kg ha-1), CGR (3.02, 6.83 & 4.15 g m-2 d-1) and SPAD value (37.56, 41.62 & 30.57) at 30, 45 DAS and harvest. The same treatments increased grain and haulm yield of 997 and 2232 kg ha-1. It also increased all agro-meteorological indices viz., GDD, HTU, PTU, RTD and HUE of green gram. However, comparable results were obtained with VBN (Gg) 4 + gypsum @ 50 % GR + CSR GROMOR @ 25 kg ha-1 + FS of brassinosteroid 0.2 ppm (M4S2).

Internally bridged nanosilica for loadings and release of sparsely soluble compounds

The engineering of a new monodisperse colloid with a sea urchin-like structure with a large complex internal structure is reported, in which silica surfaces are bridged by an aromatic organic cross-linker to serve as a nanocarrier host for drugs such as doxorubicin (DOX) against breast cancer cells. While dendritic fibrous nanosilica (DFNS) was employed and we do not observe a dendritic structure, these particles are referred to as sea urchin-like nanostructured silica (SNS). Since the structure of SNS consists of many silica fibrils protruding from the core, similar to the hairs of a sea urchin. For the aromatic structured cross-linker, bis(propyliminomethyl)benzene (b(PIM)B-S or silanated terephtaldehyde) were employed, which are prepared with terephtaldehyde and 3-aminopropyltriethoxy-silane (APTES) through a simple Schiff base reaction. b(PIM)B-S bridges were introduced into SNS under open vessel reflux conditions. SPS refers to the product obtained by incorporating the cross-linker b(PIM)B-S in ultra-small colloidal SNS particles. In-situ incorporation of DOX molecules resulted in SPS-DOX. The pH-responsive SPS nanocomposites were tested as biocompatible nanocarriers for controllable doxorubicin (DOX) delivery. We conclude that SPS is a unique colloid which has promising potential for technological applications such as advanced drug delivery systems, wastewater remediation and as a catalyst for green organic reactions in water.

Ruthenium deposited onto graphitic carbon modified with boron for the intensified photocatalytic production of benzaldehyde

The selective oxidation of added-value aromatic alcohols into aldehydes of high interest via photocatalysis has been postulated as a green and competitive oxidative reaction at mild conditions. This work is focused on the design of a tertiary graphitic carbon nitride (g-C3N4) based photocatalysts competitive for the photocatalytic production of benzaldehyde in an aqueous solution. The polymeric g-C3N4 has been modified in an easy one-pot green synthesis scheme, with the incorporation of boron in the polymeric structure and the deposition of ruthenium nanoparticles. The Ru ratio within 0.5–4% was assessed. The photocatalysts were fully characterized (XRD, FTIR, XPS, N2 isotherms, DRS-UV–visible, and PL) and the photocatalytic activity was assessed in the oxidation of benzyl alcohol to benzaldehyde in an aqueous solution. The incorporation of boron enhanced the selectivity towards benzaldehyde due to enhanced separation charges suggested by the photoluminescence technique; whereas ruthenium improved the reaction rate of the alcohol, affecting negatively the selectivity though. The sample containing 1% of Ru was selected as the optimum in terms of selectivity. The relative contribution of the involved reactive oxidant species was assessed by chemical scavenger tests, highlighting the contribution of the photo-generated holes followed by O2•‾. The analysis of the band’s alignment of the g-C3N4 before the modification with boron and ruthenium supports the enhancement by rising the redox potential of the holes released in the valence band.

Catalytic Performance of Amorphous Ti/SiO2 in the Gas‐Phase Epoxidation of Propylene with H2O2

AbstractThe epoxidation of propylene with dilute H2O2 aqueous solution over titanium silicalite‐1 (TS‐1) zeolite catalyst is a green chemical reaction for propylene oxide (PO) production. Carrying out the reaction in gas‐phase can get rid of problems caused by using methanol solvent. This paper reports an attempt of using non‐zeolite catalyst for the gas‐phase epoxidation. Amorphous Ti/SiO2, obtained by grafting amorphous SiO2 with TCl4 in ethanol solvent in a chemical liquid‐phase deposition (CLD) process, has been used as the catalyst. Results show that the CLD Ti/SiO2 with appropriate Si/Ti molar ratio is an active catalyst for gas‐phase epoxidation, achieving 9.8 % propylene conversion and 66.9 % PO selectivity with 40.3 % H2O2 utilization, which indicates that this amorphous Ti/SiO2 catalyst deserves extensive studies in the future.

A Preliminary Study of Gut Microbiota in Airline Pilots: Comparison With Construction Workers and Fitness Instructors.

The term "WORKbiota" has been used to describe the impact of occupational exposure and work types on human microbiota composition. Airline pilots, construction workers, and fitness instructors encompass three diverse professional groups, each with distinct work environments and lifestyle factors that may significantly influence their intestinal "WORKbiota." The current preliminary investigation was aimed to compare the relative abundanceof specific gut microbes among airline pilots, construction workers, and fitness instructorsto shed light on any significant differences. By scrutinizing these diverse professional groups, our objective was to enhance our understanding of how occupational factors influence gut microbiotawhile identifying possible implications for occupational medicine. A convenience sample consisting of 60 menrepresenting three different professional domains - airline pilots, construction workers, and fitness instructors (with 20 individuals in each group) - was selected during regular outpatient occupational health consultations. The abundance of selected gut microbiota constituents, including Escherichia coli, Methanobrevibacter smithii, Akkermansia muciniphila, Faecalibacterium prausnitzii, Lactobacillus spp., Bifidobacterium spp., and Bacteroides spp., was quantified using quantitative SYBR Green quantitative real-time polymerase chain reaction (qRT-PCR) in stool samples. There were no significant variations among the groups concerning Escherichia coli, Methanobrevibacter smithii, Bifidobacterium spp., and Bacteroides spp. However, Lactobacillus spp. and Faecalibacterium prausnitzii were significantly more abundant in the microbiota of fitness instructors compared to both airline pilots and construction workers, with no significant differences observed between the latter two groups. Notably, the abundance of Akkermansia muciniphila demonstrated a progressive decline from fitness instructors to construction workersand ultimately to airline pilots, who exhibited the lowest levels. Airline pilots' gut microbiota was characterized by a lower abundance of health-promoting bacterial species, including Lactobacillus spp., Faecalibacterium prausnitzii, and Akkermansia muciniphila. Future research is essential to determine whether targeted interventions, such as probiotic and prebiotic supplementation, could potentially enhance gut microbiota composition and overall health in particular occupational groups.

Rapid Synthesis of PbO-NPs Photocatalysts, Investigation of Methylene Blue Degradation Kinetics

The study focused on the green synthesis of lead oxide nanoparticles (PbO-NPs) using green tea extract and its use for photocatalytic degradation. The effect of experimental conditions such as green tea extract concentrations and reaction temperatures on the structure and size of PbO-NPs has been investigated. Reaction temperatures of 25, 50 and 85 ℃ and green tea extract concentrations of 5, 10, 20, 40, 80 and 100 mg/mL were used for preparing of PbO-NPs. Amount of the phenolic acid contained in the green tea extracts was determined according to the Folin-Cioceltau method. The synthesized PbO-NPs were further confirmed by UV–visible Spectroscopy, Fourier Infrared Transformation Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive (EDX) analysis. Tetragonal and orthorhombic morphology of PbO-NPs were observed in SEM images. While the crystallite structure of the PbO-NPs was obtained for the samples prepared using 5 and 10 mg/mL extract concentration for all reaction temperatures, the amorphous structures of PbO-NPs were seen for the samples prepared using extract concentrations of 20, 40, 80 and 100 mg/mL. Finally, PbO-NPs catalyst was tested for the degradation of methylene blue (MB) under UV light. The effect of dye concentration, catalyst amount and pH on degradation were investigated. By determining suitable experimental conditions, MB degradation reached 89% with PbO-NPs in 60 minutes. The reaction kinetics of MB removal from aqueous solution under UV lamp and in the dark media were compared for first-order and second-order reaction kinetics.

Development and evaluation of Islamic green financing: A systematic review of green sukuk

The threat of the global climate crisis demands improvement and adjustment from various sides, including the financial sector. Islamic finance responds to environmental responsibility by presenting environmentally friendly financing products in green sukuk. This study aims to show the development trend of the number of publications in green sukuk and systematize the results of studies that explain the development and evaluation of the emergence of green sukuk investments. This study analyzed 15 publications on green sukuk during the 2016-2022 years indexed by the Scopus database. As for methodology, the descriptive analysis was used to explain the green sukuk data quantitatively; the synthesis analysis was used to describe data based on four directions (the development of models (10 sources), opportunities (12 sources), challenges (12 sources), and evaluations of green sukuk (10 sources). Preferred Reporting Items for Systematic Review and Meta-Analyses standard were used to choose samples for this investigation. The green sukuk challenge is dealing with the sukuk market after the pandemic. Several evaluation findings regarding managing commitment from the government and investors for the renewable energy sector and efforts to provide low-cost sukuk financing and risk minimization are found. Green sukuk demands efficient management to be more viable, competitive, and attractive to investors if the operational area supports it. Green sukuk projects face expanding green funding, global climate financing, managing renewable energy, and validating greenhouse gas emissions. The green stock market reaction requires coordination amongst economic subsectors.

Water-based composite ink from modified chitosan and ruby nanoparticles for advanced anticounterfeiting applications

There is a huge demand for sophisticated materials and innovative strategies to create cost-effective and real-life solutions in security printing field to combat the grave threat due to forgery or counterfeiting of documents and products. In this study, nano ruby is dispersed in an eco-friendly, water-based screen-printing formulation containing modified chitosan as both luminescent colourant and resin to achieve superior security features against counterfeiting. Biopolymer chitosan is modified using 4-bromo-3-hydroxy-1,8-naphthalic anhydride through a green imidation reaction to obtain N-(6-bromo-5-hydroxy-1H-benzo[de]isoquinoline-1,3(2H)-dione) chitosan (CSNA) that display yellow fluorescence, good thermal stability, and low cytotoxicity. CSNA is used as a fluorescent resinated dye to formulate CSNA ink, devoid of any hazardous air pollutants or volatile organic compounds. To improve the security feature, ruby nanoparticles are dispersed in the CSNA ink to achieve nanoruby-CSNA (CSNAR) composite ink, which is further screen-printed on paper substrates. The CSNAR ink film exhibited advanced level security features, wherein the forger can detect only a bright yellow fluorescence from the prints under 365 nm UV light. However, the user can validate the originality of the print by viewing red and yellowish-orange emissions under specific excitation wavelengths, which is unique to the CSNAR ink, and therefore difficult for the forger to replicate. The good adhesion, lightfastness and abrasion resistance of the print combined with the multi-level security features open a new avenue for potential applications of CSNAR security inks/films in document/product authentication and packaging/pharmaceutical anti-counterfeiting applications.

Advances in the Catalytic Hydrogenation and Properties of Unsaturated Polymers

Polymer reaction and performance improvement are one of the important contents in the field of polymer materials science and engineering, in which polymer catalytic hydrogenation is an important part of polymer reaction. We reviewed the research achievements on polymer hydrogenation over the past 70 years and studied the mechanism of the hydrogenation reaction from the aspects of performance changes before and after polymer hydrogenation, the catalyst preparation/structure–activity relationship, and polymer hydrogenation kinetics. We pointed out the difficulty in separation and unsatisfactory high-temperature adaptability of traditional homogeneous catalysts and first proposed four effects affecting traditional heterogeneous polymer hydrogenation: scale effect, conformation effect, viscosity effect, and adhesion effect. Based on the structure–activity relationship of polymers, we put forward the application direction of hydrogenated polymers at present. We found that using a new kind of nanometal catalyst (Pd/CNTs@FN) as hydrogenation catalyst can effectively reduce or eliminate the negative effects of these four effects on the polymer hydrogenation reaction, and it is easy to separate from the reaction system. The addition of CNTs can effectively increase the specific surface area of the catalyst and strengthen the interaction between reactants and catalyst. Subsequent research should focus on designing the multiscale structure and improving low-temperature activity of the catalyst, reducing process cost, and using green and efficient separation methods to eliminate adverse effects, create a green and efficient polymer reaction system, accelerate the industrialization of polymer hydrogenation process, and provide theoretical guidance for the research and development of new polymer materials.

Simultaneous detection and phylogenetic analysis of porcine epidemic diarrhea virus and porcine circovirus 4 in Henan province, China.

Porcine circovirus 4 (PCV4) is a recently discovered circovirus that was first reported in 2019 in several pigs in Hunan province of China and has also been identified in pigs infected with porcine epidemic diarrhea virus (PEDV). To further investigate the coinfection and genetic diversity of these two viruses, 65 clinical samples (including feces and intestinal tissues) were collected from diseased piglets on 19 large-scale pig farms in Henan province of China, and a duplex SYBR Green I-based quantitative real-time polymerase chain reaction (qPCR) assay was developed for detecting PEDV and PCV4 simultaneously. The results showed that the limit of detection was 55.2 copies/μL and 44.1 copies/μL for PEDV and PCV4, respectively. The detection rate for PEDV and PCV4 was 40% (26/65) and 38% (25/65), respectively, and the coinfection rate for the two viruses was 34% (22/65). Subsequently, the full-length spike (S) gene of eight PEDV strains and a portion of the genome containing the capsid (Cap) gene of three PCV4 strains were sequenced and analyzed. Phylogenetic analysis showed that all of the PEDV strains from the present study clustered in the G2a subgroup and were closely related to most of the PEDV reference strains from China from 2011 to 2021, but they differed genetically from a vaccine strain (CV777), a Korean strain (virulent DR1), and two Chinese strains (SD-M and LZC). It is noteworthy that two PEDV strains (HEXX-24 and HNXX-24XIA) were identified in one sample, and the HNXX-24XIA strain had a large deletion at amino acids 31-229 of the S protein. Moreover, a recombination event was observed in strain HEXX-24. Phylogenetic analysis based on the amino acid sequence of the PCV4 Cap protein revealed that PCV4 strains were divided into three genotypes: PCV4a1, PCV4a2, and PCV4b. Three strains in the present study belonged to PCV4a1, and they had a high degree of sequence similarity (>98% identity) to other PCV4 reference strains. This study not only provides technical support for field investigation of PEDV and PCV4 coinfection but also provides data for their prevention and control.

13C NMR and Mass Spectral Analysis of 2, 5-Diarylamino-3, 6-Dichloro-1, 4-Benzoquinones Synthesized By Microwave Irradiation

Abstract: The substituted p-benzoquinones are potentially bioactive and they represent a class of compound with wide spectrum of biological activity. The microwave synthesis has received attention as new strategy for the organic synthesis due to the fact that many reactions seem to proceed with much alacrity under such conditions as opposed to thermal-assisted reactions. Apart from the enhanced reaction rate and higher yield, solvent free MWI method provided several advantages such as safe, clean and green reaction conditions, opportunity to work with open vessel, possibility to upscale the synthesis to multi-gram amount, reproducibility and convenient work-up. The characterization was done by 13C NMR and mass Spectral analysis.