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1.
Microb Pathog ; 194: 106818, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39047804

ABSTRACT

Ompok pabda is gaining popularity in the aquaculture industry due to its increasing demand; however research on microbial diversity and antibiotic susceptibility remains limited. The present study was designed to identify the bacterial pathogens commonly found in the pabda farming system with their biofilm forming potential and antibiotic susceptibility. Different bacterial strains were isolated from water, sediments and gut, gill of pabda fish and the isolates were identified based on their morphological traits, biochemical and molecular analysis. Antibiotic susceptibilities, antibiotic resistance gene determination and biofilm formation capabilities were evaluated by disc diffusion method, PCR amplification and Microtiter plate (MTP) assay, respectively. The respective isolates of gill and gut of pabda aquaculture and their environments were: Exiguobacterium spp. (25 %), Enterococcus spp. (20 %), Bacillus spp. (10 %), Acinetobacter spp. (10 %), Enterobacter spp. (10 %), Aeromonas spp. (10 %), Lactococcus spp. (5 %), Klebsiella spp. (5 %) and Kurthia spp. (5 %). Antibiotic resistance frequencies were found to be relatively high, especially for trimethoprim (95 %), sulfafurazole (75 %), ampicillin (60 %), amoxicillin-clavulanic acid (55 %), and cephradine (50 %). 30 % isolates were categorized as DR bacteria followed by 30 % isolates were MDR bacteria and 40 % were classified as XDR bacteria. Moreover, 4 antibiotic resistant genes were detected with sul1 (30 %), dfrA1 (10 %), tetC (40 %), and qnrA (5 %) of isolates. Based on the microtiter plate method, 20 %, 25 %, and 30 % of isolates were found to produce strong, moderate, and weak biofilms, respectively. The findings suggest that biofilm forming bacterial strains found in O. pabda fish farm may be a potential source of numerous antibiotic-resistant bacteria. The study sheds new light on antibiotic resistance genes, which are typically inherited by bacteria and play an important role in developing effective treatments or control strategies.

2.
Chem Rec ; 24(4): e202300234, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38530060

ABSTRACT

Silica-derived nanostructured catalysts (SDNCs) are a class of materials synthesized using nanocasting and templating techniques, which involve the sacrificial removal of a silica template to generate highly porous nanostructured materials. The surface of these nanostructures is functionalized with a variety of electrocatalytically active metal and non-metal atoms. SDNCs have attracted considerable attention due to their unique physicochemical properties, tunable electronic configuration, and microstructure. These properties make them highly efficient catalysts and promising electrode materials for next generation electrocatalysis, energy conversion, and energy storage technologies. The continued development of SDNCs is likely to lead to new and improved electrocatalysts and electrode materials. This review article provides a comprehensive overview of the recent advances in the development of SDNCs for electrocatalysis and energy storage applications. It analyzes 337,061 research articles published in the Web of Science (WoS) database up to December 2022 using the keywords "silica", "electrocatalysts", "ORR", "OER", "HER", "HOR", "CO2RR", "batteries", and "supercapacitors". The review discusses the application of SDNCs for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CO2RR), supercapacitors, lithium-ion batteries, and thermal energy storage applications. It concludes by discussing the advantages and limitations of SDNCs for energy applications.

3.
Org Biomol Chem ; 22(6): 1085-1101, 2024 02 07.
Article in English | MEDLINE | ID: mdl-38231504

ABSTRACT

Selective chemical reactions at precise amino acid residues of peptides and proteins have become an exploding field of research in the last few decades. With the emerging utility of bioconjugated peptides and proteins as drug leads and therapeutic agents, the design of smart protocols to modulate and conjugate biomolecules has become necessary. During this modification, the most important concern of biochemists is to keep intact the structural integrity of the biomolecules. Hence, a soft and selective biocompatible reaction environment is necessary. Electrochemistry, a mild and elegant tunable reaction platform to synthesize complex molecules while avoiding harsh and toxic chemicals, can provide such a reaction condition. However, this strategy is yet to be fully exploited in the field of selective modification of polypeptides. With this possibility, the use of electrochemistry as a reaction toolbox in peptide and protein chemistry is flourishing day by day. Unfortunately, there is no suitable review article summarizing the residue-specific modification of biomolecules. The present review provides a comprehensive summary of the latest manifested electrochemical approaches for the modulation of five redox-active amino acid residues, namely cysteine, tyrosine, tryptophan, histidine and methionine, found in peptides and proteins. The article also highlights the incredible potential of electrochemistry for the regio- as well as chemoselective bioconjugation strategy of biomolecules.


Subject(s)
Peptides , Proteins , Electrochemistry , Proteins/chemistry , Peptides/chemistry , Amino Acids , Methionine/chemistry
4.
Org Biomol Chem ; 22(18): 3684-3692, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38624070

ABSTRACT

Dimethyl sulfoxide (DMSO)-promoted catalyst-free oxidative C-N coupling and C-O coupling under oxidant-free conditions are outlined. This protocol is operationally simple and leads to various functionalized substituted imidazoles or oxazoles in good yields. To date, a very limited number of oxidation protocols have been established, where DMSO acts solely as a catalyst or an oxidant or both. In this report, DMSO is not only used as a C-N/C-O coupling agent but is also used as the oxidant required for these oxidative transformations. Hence, our demonstrated DMSO-promoted catalyst-free coupling transformation has the ability to lead to a new dimension in the field of oxidative coupling.

5.
J Clin Gastroenterol ; 57(5): 524-530, 2023.
Article in English | MEDLINE | ID: mdl-35470300

ABSTRACT

BACKGROUND: Although rectal administration of nonsteroidal anti-inflammatory drugs is recommended as the standard pharmacologic modality to prevent postendoscopic retrograde cholangiopancreatography (ERCP) post-ERCP pancreatitis (PEP), vigorous periprocedural hydration (vHR) with lactated Ringer's solution (LR) is emerging as an effective prophylaxis modality for PEP. There has been no head-to-head comparison between these 2. STUDY: This was a single-center, randomized, open-label, noninferiority, parallel-assigned, equal allocation, controlled clinical trial in a tertiary care hospital. Consecutive adults referred for ERCP, satisfying predefined inclusion criteria, underwent simple randomization and blinded allocation into 2 groups. Those allocated to vHR received intravenous LR at 3 mL/kg/h during procedure, 20 ml/kg bolus immediately afterward, and then at 3 mL/kg/h for another 8 hours. Those randomized to rectal Indomethacin received only per-rectal 100 mg suppository immediately post-ERCP. Assuming PEP of 9% in Indomethacin arm and noninferiority margin of 4%, we calculated sample size of 171 patients in each arm for 80% power and α-error 5%. Primary outcome was incidence of PEP, within 1 week, as defined by Cotton's criteria. All analysis were done by intention-to-treat. RESULTS: Between October, 2017 to February, 2018, 521 patients were assessed. In all, 352 were enrolled, 178 randomized to vHR, and 174 to per-rectal Indomethacin. Baseline details and ERCP outcomes were not different between 2 groups. PEP occurred in 6 (1.7%) overall, with 1 (0.6%) in hydration arm, and 5 (2.9%) in indomethacin arm; an absolute risk reduction of 2.3% (95% confidence interval: 0.9%-3.5%) and odds ratio of 0.19 (95% confidence interval: 0.02-1.65). Three patients developed severe PEP, all receiving indomethacin. CONCLUSIONS: vHR with LR is noninferior to postprocedure per-rectal Indomethacin for PEP prevention (ClinicalTrials.govID:NCT03629600).


Subject(s)
Indomethacin , Pancreatitis , Adult , Humans , Indomethacin/therapeutic use , Cholangiopancreatography, Endoscopic Retrograde/adverse effects , Anti-Inflammatory Agents, Non-Steroidal , Pancreatitis/etiology , Pancreatitis/prevention & control , Pancreatitis/epidemiology , Administration, Rectal
6.
Org Biomol Chem ; 21(39): 7928-7934, 2023 Oct 11.
Article in English | MEDLINE | ID: mdl-37766675

ABSTRACT

A stereo- and regio-selective addition of arenes to alkynes via C-H bond functionalization has been developed using palladium nanoparticles supported on graphite oxide (Pd@GO) as the reusable catalyst. The prepared catalyst was characterized by various spectroscopic techniques such as FT-IR, TEM, SEM, EDX, P-XRD, and XPS analysis. The thermal stability of the catalyst was established by TGA. The C-H functionalized products were obtained in good to excellent yields (69-92%) at room temperature. The methodology further extended to the synthesis of biologically and pharmaceutically important coumarin molecules from phenols and alkynes. Good to excellent yields of the coumarins (74-92%) were obtained. After the reaction, the catalyst was separated by centrifugation followed by filtration. The recovered catalyst was washed and reused up to five cycles. The advantages of this method are the simple procedure of the catalyst preparation, high catalytic efficiency, high selectivity, good functional group tolerance, low catalyst loading, and gram-scale synthesis.

7.
AAPS PharmSciTech ; 22(5): 163, 2021 May 24.
Article in English | MEDLINE | ID: mdl-34031790

ABSTRACT

This research aimed to develop a novel drug delivery system to improve treatment of skin disorders. The system is comprised of a Carbopol 980-based nanoemulgel (NE-gel) containing a desonide (DES; 0.05%, w/w) nanoemulsion (NE), which has a small particle size, high encapsulation efficiency, good thermodynamic stability, good permeation ability, and high skin retention. DES-loaded NE (DES-NE) was prepared by high-pressure homogenization. The developed formulation was characterized by differential scanning calorimetry (DSC), X-ray diffraction, drug release, skin permeation, and drug retention. DES in vitro release and skin permeation studies with different formulations of artificial membrane and rat abdominal skin were performed with the Franz diffusion cell system. Confocal laser scanning microscopy (CLSM) was used to detect the localization and permeation pathways of drugs in the skin. Compared with commercially available gel (CA-gel) and NE, the NE-gel release process conformed to the Higuchi release model (R2 = 0.9813). NE-gel prolonged the drug release time and allowed for reduced administration dose and frequency. The unit cumulative permeation of NE and NE-gel through the skin for 12 h was 63.13 ± 2.78 and 42.53 ± 2.06 µg/cm2, respectively, values significantly higher (p < 0.01) than that of the CA-gel (30.65 ± 1.25 µg/cm2) and CA-cream (15.21 ± 0.97 µg/cm2). The DES-NE and DES NE-gel skin drug retention was significantly higher than commercially available formulations (p < 0.01). Hence, the prepared NE-gel is a potential vehicle for improved topical DES delivery for better treatment of skin disorders.


Subject(s)
Desonide/administration & dosage , Drug Delivery Systems , Emulsions/chemistry , Nanogels/administration & dosage , Administration, Topical , Animals , Colloids/metabolism , Desonide/chemistry , Excipients/metabolism , Microscopy, Confocal , Nanogels/chemistry , Particle Size , Rats , Skin/metabolism , Skin Absorption
8.
J Org Chem ; 83(20): 12694-12701, 2018 Oct 19.
Article in English | MEDLINE | ID: mdl-30246531

ABSTRACT

A metal-free visible-light-induced phosphonylation of 2 H-indazoles with diphenylphosphine oxide has been developed using rose bengal as an organophotoredox catalyst under ambient air at room temperature. A library of diphenyl(2-phenyl-2 H-indazol-3-yl)phosphine oxide with broad functionalities has been synthesized in high yields. The experimental result suggests the radical pathway of the reaction.

9.
Org Biomol Chem ; 14(9): 2706-15, 2016 Mar 07.
Article in English | MEDLINE | ID: mdl-26837413

ABSTRACT

A new general method for the synthesis of acridine-1,8-diones through CDC coupling of enamino-ketones followed by rearrangement has been developed. This is a Cu(i) catalyzed procedure, based on the cross dehydrogenative coupling of the Csp(3)-H bond with the Csp(2)-H bond of enamino-ketones followed by rearrangement to acridine-1,8-diones in the presence of PTSA under an aerobic atmosphere. The synthetic route has been broadly applicable to a wide range of enamino-ketone derivatives derived from different benzyl amines as well as primary aliphatic amines having Cα(sp(3))-H bonds with various cyclic, acyclic 1,3-diketones and also using DEAD.

10.
Org Biomol Chem ; 13(48): 11674-86, 2015 Dec 28.
Article in English | MEDLINE | ID: mdl-26477587

ABSTRACT

A new family of novel highly fluorescent π-conjugated, C7-imidazole based indolizine derivatives has been prepared in good to excellent yields, catalysed by l-proline in acetonitrile. These are π-conjugated, C7-imidazole based indolizine derivatives covering the emission wavelength range 423-449 nm in acetonitrile with high quantum yields at 25 °C. A thorough photophysical study of all the compounds has been carried out to understand the π-conjugated electronic effect of the imidazole moiety fused at the C7 position on the indolizine motif. In addition, a comparative photophysical study of three selective fluorophores was also carried out in a wide variety of solvents at 25 °C. Finally, the molecular orbitals of the two representative compounds were investigated through DFT calculations to illustrate the pi-conjugate effect.


Subject(s)
Fluorescent Dyes/chemical synthesis , Imidazoles/chemistry , Indolizines/chemistry , Light , Catalysis , Fluorescent Dyes/chemistry , Molecular Structure , Proline/chemistry , Solvents/chemistry
11.
Angew Chem Int Ed Engl ; 54(1): 293-7, 2015 Jan 02.
Article in English | MEDLINE | ID: mdl-25293372

ABSTRACT

Superconducting [(Li1-x Fex )OH](Fe1-y Liy )Se (x≈0.2, y≈0.08) was synthesized by hydrothermal methods and characterized by single-crystal and powder X-ray diffraction. The structure contains alternating layers of anti-PbO type (Fe1-y Liy )Se and (Li1-x Fex )OH. Electrical resistivity and magnetic susceptibility measurements reveal superconductivity at 43 K. An anomaly in the diamagnetic shielding indicates ferromagnetic ordering near 10 K while superconductivity is retained. The ferromagnetism is from the iron atoms in the (Li1-x Fex )OH layer. Isothermal magnetization measurements confirm the superposition of ferromagnetic and superconducting hysteresis. The internal ferromagnetic field is larger than the lower, but smaller than the upper critical field of the superconductor. The formation of a spontaneous vortex phase where both orders coexist is supported by (57) Fe-Mössbauer spectra, (7) Li-NMR spectra, and µSR experiments.

12.
Cureus ; 16(4): e59026, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38800175

ABSTRACT

Limb body wall complex (LBWC), also known as body stalk anomaly, is a rare and lethal disorder of the anterior abdominal wall. It is characterized by a severe combination of congenital malformations in the fetus, including, abdomino- and/or thoracoschisis, exencephaly/encephalocele, limb deformities, and facial clefts. Short umbilical cord, abdominal placental attachment, and spinal anomalies are among other manifestations of this disorder. The cause of LBWC is still unknown. The main hypotheses include embryonic dysplasia, early amniotic rupture, and vascular accident during embryonic development. We present a case of LBWC that was detected prenatally on ultrasound (USG) imaging and later confirmed postnatally in a Rh-negative mother at the menstrual age of 14 weeks.

13.
Chem Commun (Camb) ; 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38913168

ABSTRACT

With the versatile utility of bio-conjugated peptides and proteins in the fields of agriculture, food, cosmetics and pharmaceutical industry, the design of smart protocols to conjugate and modulate biomolecules becomes highly desirable. During this process, the most important consideration for biochemists is the retention of configurational integrity of the biomolecules. Moreover, this type of bioconjugation of peptide and protein becomes frivolous if the reaction is not performed with precise amino acid residues. Hence, chemo-selective, as well as site-selective reactions, that are biocompatible and possess an appropriate level of reactivity are necessary. Based on click chemistry, there are so many tyrosine (Y) conjugation strategies, such as sulfur-fluoride exchange (SuFEx), sulfur-triazole exchange (SuTEx), coupling with π-allyl palladium complexes, diazonium salts, diazodicarboxyamide-based reagents etc. Among these techniques, diazodicarboxyamide-based Y-conjugation, which is commonly known as the "tyrosine-click (Y-click) reaction", has met the expectations of synthetic and biochemists for the tyrosine-specific functionalization of biomolecules. Over the past one and a half decades, significant progress has been made in the classical organic synthesis approach, as well as its biochemical, photochemical, and electrochemical variants. Despite such progress and increasing importance, the Y-click reaction has not been reviewed to document variations in its methodology, applications, and broad utility. The present article aims to provide a summary of the approaches for the modulation of biomolecules at the hotspot of tyrosine residue by employing the Y-click reaction. The article also highlights its application for the mapping of proteins, imaging of living cells, and in the fields of analytical and medicinal chemistry.

14.
J Phys Condens Matter ; 36(39)2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38906131

ABSTRACT

Considering the low-energy model of tilted Weyl semimetal, we study the electronic transmission through a periodically driven quantum well, oriented in the transverse direction with respect to the tilt. We adopt the formalism of Floquet scattering theory and investigate the emergence of Fano resonances as an outcome of matching between the Floquet sidebands and quasi-bound states. The Fano resonance energy changes linearly with the tilt strength suggesting the fact that tilt-mediated part of quasi-bound states energies depends on the above factor. Given a value of momentum parallel (perpendicular) to the tilt, we find that the energy gap between two Fano resonances, appearing for two adjacent values of transverse (collinear) momentum with respect to the tilt direction, is insensitive (sensitive) to the change in the tilt strength. Such a coupled (decoupled) behavior of tilt strength and the collinear (transverse) momentum can be understood from the tilt-mediated and normal parts of the quasi-bound state energies inside the potential well. We vary the other tilt parameters and chirality of the Weyl points to conclusively verify the exact form of the tilt-mediated part of the quasi-bound state energy that is the same as the tilt term in the static dispersion. The tilt orientation can significantly alter the transport in terms of evolution of Fano resoance energy with tilt momentum. We analytically find the explicit form of the bound state energy that further supports all our numerical findings. Our work paves the way to probe the tilt-mediated part of quasi-bound state energy to understand the complex interplay between the tilt and Fano resonance.

15.
ACS Appl Energy Mater ; 7(14): 5679-5690, 2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39055071

ABSTRACT

Nickel phosphides are an emerging class of earth-abundant catalysts for hydrogen generation through water electrolysis. However, the hydrogen evolution reaction (HER) activity of Ni2P is lower than that of benchmark Pt group catalysts. To address this limitation, an integrated theoretical and experimental study was performed to enhance the HER activity and stability of hexagonal Ni2P through doping with synergistic transition metals. Among the nine dopants computationally studied, zinc emerged as an ideal candidate due to its ability to modulate the hydrogen binding free energy (ΔG H) closer to a thermoneutral value. Consequently, phase pure hexagonal Ni2-x Zn x P nanocrystals (NCs) with a solid spherical morphology, variable compositions (x = 0-17.14%), and size in the range of 6.8 ± 1.1-9.1 ± 1.1 nm were colloidally synthesized to investigate the HER activity and stability in alkaline electrolytes. As predicted, the HER performance was observed to be composition-dependent with Zn compositions (x) of 0.03, 0.07, and 0.15 demonstrating superior activity with overpotentials (η-10) of 188.67, 170.01, and 135.35 mV, respectively at a current density of -10 mA/cm2, in comparison to Ni2P NCs (216.2 ± 4.4 mV). Conversely, Ni2-x Zn x P NCs with x = 0.01, 0.38, 0.44, and 0.50 compositions showed a notable decrease in HER activity, with corresponding η-10 of 225.3 ± 3.2, 269.9 ± 4.3, 276.4 ± 3.7 and 263.9 ± 4.9 mV, respectively. The highest HER active catalyst was determined to be Ni1.85Zn0.15P NCs, featuring a Zn concentration of 5.24%, consistent with composition-dependent ΔG H calculations. The highest performing Ni1.85Zn0.15P NCs displayed a Heyrovsky HER mechanism, enhanced kinetics and electrochemically active surface area (ECSA), and superior corrosion tolerance with a negligible increase of η-10 after 10 h of continuous HER. This study provides critical insights into enhancing the performance of metal phosphides through doping-induced electronic structure variation, paving the way for the design of high-efficiency and durable nanostructures for heterogeneous catalytic studies.

16.
Hepatology ; 55(2): 584-93, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21952989

ABSTRACT

UNLABELLED: The liver stiffness measure (LSM) needs to be explored in ethnically and anthropometrically diverse healthy subjects (to derive an acceptable normal range) and also in patients with liver disease. In view of this objective, LSM was performed by transient elastography (TE) using FibroScan in 437 healthy subjects with normal alanine aminotransferase (ALT) levels, recruited from a free-living population of the Birbhum Population Project (BIRPOP; www.shds.in), a Health and Demographic Surveillance System (HDSS), and from 274 patients with liver disease attending the Hepatology Clinic of the School of Digestive and Liver Diseases (SDLD; Institute of Post Graduate Medical Education & Research [IPGME&R], Kolkata, India) including 188 with nonalcoholic fatty liver disease (NAFLD) and 86 with chronic hepatitis of viral and other etiologies. Liver biopsy was performed in 125 patients. The range of normal values for LSM, defined by 5th and 95th percentile values in healthy subjects, was 3.2 and 8.5 kPa, respectively. Healthy subjects with a lower body mass index (BMI; < <18.5 kg/m(2)) had a higher LSM compared with subjects who had a normal BMI; this LSM value was comparable to that of obese subjects (6.05 ± 1.78 versus 5.51 ± 1.59 and 6.60 ± 1.21, P = 0.016 and 0.349, respectively). Liver disease patients without histologic fibrosis had significantly higher LSM values compared with healthy subjects (7.52 ± 5.49 versus 5.63 ± 1.64, P < 0.001). Among the histologic variables, stage of fibrosis was the only predictor for LSM. LSM did not correlate with inflammatory activity and ALT in both NAFLD and chronic hepatitis groups. CONCLUSION: LSM varies between 3.2 and 8.5 kPa in healthy subjects of South Asian origin. Both lean and obese healthy subjects have higher LSM values compared with subjects with normal BMI. Liver stiffness begins to increase even before fibrosis appears in patients with liver disease.


Subject(s)
Elasticity , Liver Cirrhosis/diagnosis , Liver Diseases/diagnosis , Liver , Adult , Case-Control Studies , Developing Countries , Elasticity Imaging Techniques , Female , Humans , India , Liver/physiopathology , Liver Diseases/physiopathology , Male , Middle Aged , Obesity/physiopathology , ROC Curve , Reference Values
17.
Article in English | MEDLINE | ID: mdl-37903332

ABSTRACT

Assembly of nanoparticles (NPs) into functional macrostructures is imperative for the development of NP-based devices. However, existing methods employ insulating organic ligands, polymers, and biomolecules as mediators for the NP assembly, which are detrimental for charge transport and interparticle coupling that impede the efficient integration of low-dimensional properties. Herein, we report a methodology for the direct self-supported assembly of Ag/Pt/Pd alloy NPs into high surface area (119.1 ± 3.9 to 140.1 ± 5.7 m2/g), mesoporous (19.7 ± 6.2 to 23.0 ± 1.6 nm), and conducting nanostructures (aerogels) that show superior electrocatalytic activity and stability in methanol (MOR) and ethanol (EOR) oxidation reactions. Ultrasmall (3.9 ± 1.3 nm) and quasi-spherical Ag/Pt/Pd alloy NPs were synthesized via stepwise galvanic replacement reaction (GRR) of glutathione (GSH)-coated Ag NPs. As-synthesized NPs were transformed into free-standing alloy hydrogels via chemical oxidation of the GSH ligands. The composition of alloy aerogels was tuned by varying the oxidant/thiolate molar ratio of the precursor NP sol that prompts Ag dealloying with in situ generated HNO3, selectively enriching the Pt and Pd catalytic sites on the aerogel surface. The highest-performing alloy aerogel (Ag0.449Pt0.480Pd0.071) demonstrates excellent mass activity for methanol (3179.5 mA/mg) and ethanol (2444.5 mA/mg) electro-oxidation reactions, which are ∼4-5 times higher than those of commercial Pt/C and Pd/C electrocatalysts. The aerogel also maintained high alcohol oxidation activity for 17 h at a constant potential of -0.3 V in an alkaline medium. The synergistic effects of noble metal alloying, high surface area and mesoporosity, and the pristine active surface of aerogels provide efficient interaction of analytes with the nanostructure surface, facilitating both MOR and EOR activity and improving tolerance for poisonous byproducts, enabling the Ag/Pt/Pd alloy aerogel a promising (electro)catalyst for a number of new technologies.

18.
Chem Commun (Camb) ; 59(50): 7771-7774, 2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37264649

ABSTRACT

Our study describes a new development featuring iodine-catalyzed two consecutive oxidative cross-coupling reactions involving Cα(sp3)-H of benzyl amines followed by intramolecular cyclization in water under air. Here, C-N coupling followed by C-C coupling occurs in a green environment to provide a variety of 5H-pyrazino[2,3-b]indoles within a short time period.

19.
Sci Rep ; 13(1): 12908, 2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37558730

ABSTRACT

A heterogeneous copper-catalyzed A3 coupling reaction of aldehydes, amines, and alkynes for the synthesis of propargylamines and benzofurans has been developed. Here, the modified metal-organic framework MIL-101(Cr)-SB-Cu complex was chosen as the heterogeneous copper catalyst and prepared via post-synthetic modification of amino-functionalized MIL-101(Cr). The structure, morphology, thermal stability, and copper content of the catalyst were determined by FT-IR, PXRD, SEM, TEM, EDX, TGA, XPS, and ICP-OES. The catalyst shows high catalytic activity for the aforementioned reactions under solvent-free reaction conditions. High yields, low catalyst loading, easy catalyst recovery and reusability with not much shrink in catalytic activity, and a good yield of 82% in gram-scale synthesis are some of the benefits of this protocol that drove it towards sustainability.

20.
Food Chem X ; 17: 100577, 2023 Mar 30.
Article in English | MEDLINE | ID: mdl-36845496

ABSTRACT

Studies are being carried out on achieving the maximum quality of garlic through various approaches. In Bangladesh, new garlic varieties (BARI 1-4, BAU-1, BAU-2, BAU-5) have been recently developed by artificial selection to enhance their quality. The present study aimed to evaluate their potency in terms of bioactive properties and organosulfur compounds content using different bioassay and GC-MS techniques while comparing them with other accessible varieties (Chinese, Indian, Local). The new variety, BARI-3 showed the highest antioxidant activity and total phenolic content. It was also found with the highest level of a potent blood pressure-lowering agent, 2-vinyl-4H-1,3-dithiine (78.15 %), which is never reported in any garlic at this percentage. However, the local variety exhibited greater inhibitory properties against the tested organisms including multidrug-resistant pathogens compared to other varieties. This study primarily shows the potential of these two kinds of garlic for their further utilization and development.

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