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1,3-Bis(cyanomethoxy)calix[4]arene capped CdSe quantum dots for the fluorogenic sensing of fluorene
(Royal Society of Chemistry, 2017) Kumar, Rabindra; Arora, Meenu; Jain, A.K.; Babu, J. Nagendra
Capping of 1,3-bis(cyanomethoxy)-tert-butylcalix[4]arene (CAD) onto CdSe quantum dots (QDs) was characterized by a fluorescence enhancement of the QDs (?em = 580 nm) upon surface interaction with the phenolic moiety of CAD. CAD@QD showed selective and sensitive 1.67 fold fluorescence enhancement in the presence of fluorene among fifteen PAHs. The fluorescence enhancement was characterized by monolayer adsorption of fluorene on to the surface of CAD@QD. The limit of detection for fluorene was observed to be 0.8 nM. This method was used and compared with detection of fluorene in spiked respirable dust (PM10) samples collected during an open biomass (stubble) burning event. ? The Royal Society of Chemistry.
1,3-Oxazine as a Promising Scaffold for the Development of Biologically Active Lead Molecules
(John Wiley and Sons Inc, 2023-10-16T00:00:00) Gupta, Nidhi; Saini, Vipin; Basavarajaiah, S.M.; Dar, Mohammad Ovais; Das, Rina; Dahiya, Randhir Singh
Heterocyclic compounds form an important part of wide range of biologically active molecules. The heteroatom provides them specificity for various receptors. 1,3-oxazine has been considered as a privileged scaffold in many medicinal chemistry applications. Compounds having 1,3-oxazine moiety exhibit broad range of biological applications such as anticancer, antimicrobial, anti-inflammatory, antiplatelet, antitubercular and alpha-glucosidase inhibition activities. In this review, we consolidate the recent developments in the synthesis and biological activities of 1,3-oxazine containing compounds. Also, the structure activity relationship (SAR) studies of different derivatives exhibiting several biological activities are summarized. Database such as Science direct, Pubmed and Google scholar were searched using keywords �1,3-Oxazine�, �synthesis�, �derivatives�, and �biological activities�. The review would provide a lead for the development of competent candidates with 1,3-oxazine moiety having broad range of applications in the treatment of several human disorders. � 2023 Wiley-VCH GmbH.
1-Acetyl-3, 5?diaryl-4, 5?dihydro (1H) pyrazoles: Exhibiting Anticancer Activity through Intracellular ROS Scavenging and the Mitochondria-Dependent Death Pathway
(Wiley, 2014) Alex, JM; Singh, S; Kumar, Raj
A series of 17 analogs of 1?acetyl?4,5?dihydro(1H)pyrazoles (JP?1 to JP?17) bearing two aromatic rings at positions 3 and 5, either of which ought to be heterocyclic, were synthesized and evaluated for their anti?proliferative potential against breast cancer (MCF?7 and T?47D) and lung cancer (H?460 and A?549) cell lines for the first time.JP-1–7, -10, -11, -14, and ?15 were observed to exhibit significant anti?proliferative activity against MCF?7 cells. Some notions about structure - activity relationships are reported. The investigated compounds were found to lower the intracellular reactive oxygen species in the H2DCFDA assay and also caused mitochondria?dependent cell death in the MCF?7 cell line, indicating a plausible mechanism of their anticancer effect.
1-Acetyl-3,5-diaryl-4,5-dihydro(1H)pyrazoles: Exhibiting anticancer activity through intracellular ROS scavenging and the mitochondria-dependent death pathway
(Wiley-VCH Verlag, 2014) Alex, Jimi M.; Singh, Sandeep; Kumar, Raj
A series of 17 analogs of 1-acetyl-4,5-dihydro(1H)pyrazoles (JP-1 to JP-17) bearing two aromatic rings at positions 3 and 5, either of which ought to be heterocyclic, were synthesized and evaluated for their anti-proliferative potential against breast cancer (MCF-7 and T-47D) and lung cancer (H-460 and A-549) cell lines for the first time. JP-1-7, -10, -11, -14, and -15 were observed to exhibit significant anti-proliferative activity against MCF-7 cells. Some notions about structure-activity relationships are reported. The investigated compounds were found to lower the intracellular reactive oxygen species in the H2DCFDA assay and also caused mitochondria-dependent cell death in the MCF-7 cell line, indicating a plausible mechanism of their anticancer effect. Analogs of 1-acetyl-4,5-dihydro(1H)pyrazoles (JP-1-17) were synthesized and evaluated for their anti-proliferative activity in four cancer cell lines and for their intracellular ROS scavenging properties. An attempt was made to determine the mitochondrial membrane potential of MCF-7 cells treated with JP-1 and -14, aiming to elucidate the mechanism by which proliferation was curbed. ? 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
1-Hydroxypyrene-based micelle-forming sensors for the visual detection of RDX/TNG/PETN-based bomb plots in water
(Royal Society of Chemistry, 2018) Kovalev I.S.; Taniya O.S.; Kopchuk D.S.; Giri K.; Mukherjee A.; Santra S.; Majee A.; Rahman M.; Zyryanov G.V.; Bakulev V.A.; Chupakhin O.N.
The high-lying LUMO energy levels of common aliphatic nitro-explosives require special approaches for the proper synthetic design of fluorescence chemosensors that are capable to detect ultra-trace amounts of these explosives via photo-induced electron transfer (PET) fluorescence quenching. Herein, 1-hydroxypyrene has been used as a synthetic platform to prepare a number of water soluble micelle-forming fluorescent chemosensors possessing high-lying LUMO levels. Based on these sensors a cheap and highly efficient method has been described for the detection of low-volatile aliphatic nitro explosives, such as 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), pentaerythritoltetranitrate (PETN), and high volatile taggants/propellants, such as 2,3-dimethyldinitrobutane (DMDNB) or trinitroglycerin (TNG) in aqueous solutions and in vapor phase. The applicability of the sensors for the detection of nitro-explosives was fully confirmed based on the fluorescence quenching titration experiments, with the corresponding Stern–Volmer constants as high as 6.0 × 105 M−1 and the limit of detection (LOD) as low as 12 ppb. The “sphere of action” quenching mechanism has been proposed. To support this, the DFT calculations of the possible molecular complexes between the sensors and nitro-analytes were performed along with the calculations of the quenching sphere radii for the Perrin's model.
1951 Refugee Convention and its Protocol: Imperatives to Indian Perspective.
(IMPACT, 2018) Noushadali, K; Kaushiki, Nishtha
Being not a signatory to the notable International legal provisions passed for the betterment of refugees such as the United Nations Convention (1951) and protocol (1967), the Indian approach towards the refugees is worthy to do researches. It is for this reason that India responds sympathetically towards its refugee population following the principles of humanitarian considerations. Further, it is interesting to see that the Indian constitution is assuring some definite fundamental freedom to all without discriminating citizens and non-citizens. In order to preserve the fundamental freedoms of the foreigners and of course refugees (non-citizens), the Indian government had given them judicial backup too. This paper is an attempt to look at the importance of the International refugee conventions for the holistic betterment of the global refugee population. Further, the paper outlines the Indian perspectives on the global refugee laws and conventions. It also emphasizes that the Indian constitution and judiciary plays an important role in accommodating refugees, in relation to its political others, as well as ethnic affinities.
2-(2-Arylphenyl) benzoxazole As a Novel Anti-Inflammatory Scaffold: Synthesis and Biological Evaluation
(ACS publications, 2014) Seth, Kapileswar; Garg, Sanjeev K.; Kumar, Raj; Purohit, Priyank; Meena, Vachan S.; Goyal, Rohit; Banerjee, Uttam C.; Chakraborti, Asit K.
The 2-(2-arylphenyl)benzoxazole moiety has been found to be a new and selective ligand for the enzyme cyclooxygenase-2 (COX-2). The 2-(2-arylphenyl)benzoxazoles 3a−m have been synthesized by Suzuki reaction of 2-(2-bromophenyl)benzoxazole. Further synthetic manipulation of 3f and 3i led to 3o and 3n, respectively. The compounds 3g, 3n, and 3o selectively inhibited COX-2 with selectivity index of 3n much better than that of the COX-2 selective NSAID celecoxib. The in vivo anti-inflammatory potency of 3g and 3n is comparable to that of celecoxib and the nonselective NSAID diclofenac at two different doses, and 3o showed better potency compared to these clinically used NSAIDs.
The 22 June 2020 Mizoram, India earthquake (Mw5.5): an unusual intra-wedge shallow earthquake in the Indo-Burmese Wedge
(Indian Academy of Sciences, 2022-03-08T00:00:00) Malsawma, J.; Lalnuntluanga, Paul; Sailo, Saitluanga; Vanthangliana, V.; Tiwari, R.P.; Gahalaut, V.K.
Earthquakes in the Indo-Burmese arc occur due to interaction of India and Sunda plates along the Indo- Burmese Wedge and Sagaing Fault. Majority of the moderate to major magnitude earthquakes in the Indo-Burmese Wedge occur within the Indian slab and very few of them occur on the plate interface. Earthquakes within the wedge are rare and the 22 June 2020 earthquake of magnitude 5.5 (Mw) on the India�Myanmar border in Mizoram, India, at shallow depth is probably one such earthquake. The earthquake caused moderate damage (maximum intensity VIII on MSK scale) in remote border villages (Vaphai and Chawngtui) with sparse population without any fatality. The earthquake did not seem to be related with the Mat Fault, which was transverse to the north�south trending wedge, as various estimates of mainshock and the region of maximum damage was ~20 km northeast of the surface trace of the Mat Fault. It appeared to be associated with almost north� south oriented Churachandpur Mao Fault (CMF) with dextral slip which mapped extensively and monitored geodetically in the neighbouring regions of Manipur and Nagaland to the north. Occurrence of this shallow depth earthquake may imply that some segment of the CMF might be seismically active, unlike in the north, where it appears to be predominantly aseismic. This implies that the seismic hazard along the CMF may vary along its length. � 2021. All Rights Reserved.
24-Epibrassinolide pre-treatment reduces alkaline-induced oxidative stress in red rice seedlings
(Springer, 2019) Sharma, M; Mahajan, P; Singh, H.P; Batish, D.R; Kohli, R.K.
Soil alkalinity caused by salts, such as sodium bicarbonate (NaHCO3), and the frequently associated waterlogging problems are pervasive in agriculture and have a deleterious impact on crop production. However, various plant growth regulators, including brassinosteroids, are considered to be important against different abiotic stresses experienced by plants due to drought, salinity, and heavy metal stress. We investigated the putative role of 24-epibrassinolide (EBL), an active brassinosteroid, on red rice plants experiencing alkaline stress. Seedlings were pre-treated with 0.01 μM EBL for 30 min and later, exposed to NaHCO3 (25 mM) and were sampled, 5 days after treatments. Results showed that the pre-treatment of seedlings with EBL under non-stress conditions could promote rice plant growth. Growth parameters including dry weight (DW), root and coleoptile lengths were reduced under alkaline stress, whereas EBL application reduced the level of inhibition, as compared with NaHCO3 treatment. Enhanced levels of malondialdehyde content, hydrogen peroxide, and superoxide radicals were significantly diminished by EBL pre-treatment. Moreover, pre-treatment of EBL to alkaline-treated rice seedlings largely stimulated the enzymatic activities of ascorbate peroxidase, catalase, and superoxide dismutase. Thus, the results suggest that pre-application of EBL significantly ameliorates alkaline stress in rice. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
2D layered transition metal dichalcogenides (MoS2): Synthesis, applications and theoretical aspects
(Elsevier, 2018) Singh, Arun Kumar; Kumar, P.; Late, D.J.; Kumar, Ashok; Patel, S.; Singh, Jai
Recently, graphene and other two-dimensional (2D) transition metal dichalcogenides (TMDCs) have been widely explored due to their unique optical, mechanical, electrical and sensing properties for versatile electronic and optoelectronic applications. The atomically thin layers of TMDC materials have shown potential to replace state-of-the-art silicon-based technology. Graphene has already revealed an excess of new physics and multifaceted applications in several areas. Similarly, mono-layers of TMDCs such as molybdenum disulfide (MoS2) have also shown excellent electrical and optical properties possessing a direct band-gap of ∼1.8 eV combined with high mechanical flexibility. In contrast to semi-metallic graphene, the semiconducting behavior of MoS2 allows it to overcome the deficiencies of zero-band-gap graphene. This review summarizes the synthesis of 2D MoS2 by several techniques, i.e., mechanical and chemical exfoliation, RF-sputtering, atomic layer deposition (ALD) and chemical vapor deposition (CVD), etc. Furthermore, extensive studies based on potential applications of MoS2 such as the sensor, solar cells, field emission and as an efficient catalyst for hydrogen generation has been included. Theoretical aspects combined with the experimental observations to provide more insights on the dielectric, optical and topological behavior of MoS2 was highlighted.
2D layered transition metal dichalcogenides (MoS2): Synthesis, applications and theoretical aspects
(Elsevier Ltd, 2018) Singh, Arun Kumar; Kumar, P.; Late, D.J.; Kumar, Ashok; Patel, S.; Singh, Jai
Recently, graphene and other two-dimensional (2D) transition metal dichalcogenides (TMDCs) have been widely explored due to their unique optical, mechanical, electrical and sensing properties for versatile electronic and optoelectronic applications. The atomically thin layers of TMDC materials have shown potential to replace state-of-the-art silicon-based technology. Graphene has already revealed an excess of new physics and multifaceted applications in several areas. Similarly, mono-layers of TMDCs such as molybdenum disulfide (MoS2) have also shown excellent electrical and optical properties possessing a direct band-gap of ?1.8 eV combined with high mechanical flexibility. In contrast to semi-metallic graphene, the semiconducting behavior of MoS2 allows it to overcome the deficiencies of zero-band-gap graphene. This review summarizes the synthesis of 2D MoS2 by several techniques, i.e., mechanical and chemical exfoliation, RF-sputtering, atomic layer deposition (ALD) and chemical vapor deposition (CVD), etc. Furthermore, extensive studies based on potential applications of MoS2 such as the sensor, solar cells, field emission and as an efficient catalyst for hydrogen generation has been included. Theoretical aspects combined with the experimental observations to provide more insights on the dielectric, optical and topological behavior of MoS2 was highlighted.
2D Nanomaterials in Diagnostics and Therapy of Cardiovascular Diseases
(CRC Press, 2022-09-26T00:00:00) Yadav, Pooja; Beura, Samir K.; Panigrahi, Abhishek R.; Chatterjee, Abhinaba; Yadav, Jyoti; Singh, Sunil K.
[No abstract available]
2D-HfS 2 as an efficient photocatalyst for water splitting
(Royal Society of Chemistry, 2016) Singh, Deobrat; Gupta, Sanjeev K.; Sonvane, Yogesh; Kumar, Ashok; Ahuja, Rajeev
Two dimensional monolayer nanostructures for water splitting solar photocatalysts are drawing more attention due to their extraordinary properties. Using first principles calculations we have systematically investigated the structural, electronic and vibrational properties of corresponding HfS2 monolayers in both hexagonal (1H) and trigonal (1T) phases. The most stable adsorption configurations and adsorption energies are calculated. The adsorption energy of H2O on the substrate is 646.53 kJ mol−1 for the 1H-phase and 621.65 kJ mol−1 for the 1T-phase of HfS2. This shows that H2O molecules have a stronger interaction with the HfS2 substrate. The calculated redox potentials of H2O splitting lie properly astride the valence and conduction bands, suggesting that the monolayers of 1H- and 1T-HfS2 show the same characteristics as a photocatalyst for water splitting. Furthermore, we also calculated that the optical band gaps for the 1H and 1T phases of HfS2 are 2.60 eV and 3.10 eV, respectively. We have also calculated Raman spectrum signatures of the monolayer 1H and 1T-phase of the in-plane vibrational mode of the Hf and S atoms (E1g) and the out-of-plane vibrational mode of S atoms (A1g and A2u). Our work suggests that a lot more research and attention in this field is needed for the practical application of the material as visible light active photocatalysts.
The (3 + 1)-dimensional Benjamin-Ono equation: Painlev� analysis, rogue waves, breather waves and soliton solutions
(World Scientific, 2022-06-08T00:00:00) Kumar, Sachin; Malik, Sandeep
In this paper, we analyzed the (3 + 1)-dimensional Benjamin-Ono (BO) equation. We first demonstrated that the governing model is not integrable in the Painlev� sense. The rogue wave and the breather wave solutions are then achieved with the use of bilinear form. Furthermore, using a combination of Lie symmetry analysis with the new Kudryshov method, and the Riccati equation technique, the abundant soliton and singular periodic solutions were derived. The criteria for existence of such solutions are also provided. Consequently, the derived solutions are presented graphically through 3D, 2D and contour plots, which describe useful physical phenomena due to existence of the free parameters. Corresponding to the one-reduction, power series solution of BO equation is also obtained. � 2022 World Scientific Publishing Company.
3-Cyano-2-azaanthracene-based ‘‘push-pull” fluorophores: A one-step preparation from 5-cyano-1,2,4-triazines and 2,3-dehydronaphthalene, generated in situ
(Elsevier, 2016) Kopchuk, Dmitry S.; Chepchugov, Nikolay V.; Taniya, Olga S.; Khasanov, Albert F.; Giri,Kousik; Kovalev, Igor S.; Santara, Saugata; Zyryanov, Grigory V.; Majee, Adinath; Rusinov, Vladimir L.; Chupakhin, Oleg N.
A facile one-step approach towards 3-cyano-2-azaanthracenes via the [4+2] cycloaddition reaction between 5-cyano-1,2,4-triazines and 2,3-dehydronaphthalene, generated in situ from commercially available 3-amino-2-naphthoic acid, has been reported. The influence of the 1,2,4-triazine ring sub- stituents nature on the product yield has been studied. The observed experimental results were con- firmed by DFT calculations of the HOMO-LUMO energy levels of the both cycloaddends. The photophysical properties of the products have been investigated.
3-D QSAR Study Of Combretastatins Fused With Hetrocyclic Ring As Tubulin Binding Agents
(Central University of Punjab, 2018) Dhanka, Ajit Kumar; Kumar, Vinod
Combretastatin A4 (CA4) is a leading agent in vascular disrupting strategies and tubulin polymerization inhibitor for the tumour therapy. A large number of combretastatin derivatives have been synthesized as potent inhibitors of Tubulin which are responsible for the anticancer activity. Combretastatins bind with the colchicine binding site of the tubulin and disrupt the dynamic equilibrium of tubulin. IN the current research proposal we have performed 3D-Field based QSAR on Combretastatins analogue in order to recognize structural features which are responsible for the tubulin inhibitors activity. The designed compounds are expected to show good inhibitory activity against tubulin when electrostatic group is attached in case of compounds 16 and 18, Bulky group is attached in case of compound 26 and hydrophobic group is attached in case of compound 51 respectively.
3D modelling and visualization for Vision-based Vibration Signal Processing and Measurement
(De Gruyter Open Ltd, 2021-04-10T00:00:00) Yao, Qi; Shabaz, Mohammad; Singh, Raj Karan; Lohani, Tarun Kumar; Bhatt, Mohammed Wasim; Panesar, Gurpreet Singh
With the technological evolutionary advent, a vision-based approach presents the remote measuring approach for the analysis of vibration. The structure vibration test and model parameter identification in the detection of the structure of the bridge evaluation occupies the important position. The bridge structure to operate safely and reliably is ensured, according to the geological data of qixiashan lead-zinc mine and engineering actual situation, with the aid of international mining software Surpac. To build the 3D visualization model of the application of visualization in mine production are discussed. The results show that the final solid model of -425 stope can accurately display the spatial form of each layer of stope through rotation, amplification and movement. The proposed system is effectually able to perform cutting, volume calculation and roaming in any direction, which has certain guiding significance for mine production management. An accuracy value of 98.75%, the sensitivity of 99%, specificity of 99.64% and PPV of 99.89% are achieved using the proposed 3D modelling and visualization algorithm for vibration signal processing and management. � 2021 Q. Yao et al., published by De Gruyter.
4,5-Dihydro-1H-pyrazole: An indispensable scaffold
(Informa Healthcare, 2014) Alex, Jimi Marin; Kumar, Raj
Pyrazoles, categorized as nitrogen-containing heterocycles, are well known for their interminable participation in the field of perpetual research and development of therapeutical active agents. As a consequence pyrazoles became an inevitable core of numerous drugs having diverse activities. The broad spectrum of activities portrayed by the pyrazoles instigated the researchers to modify the pyrazole ring as 4,5-dihydro-1H-pyrazoles commonly known as 2-pyrazolines. The present review is a concerted effort to retrace compounds covered from 2009-till date which owe diverse biological activities to the 2-pyrazoline scaffold and also condenses the retro-synthetic approaches employed for their synthesis. This endeavor culminated in revelation that inhibitory potential varied when the substituents in particular N-substituents of 2-pyrazolines were altered. ? 2014 Informa UK Ltd.
4,6-Diphenylpyrimidine Derivatives as Dual Inhibitors of Monoamine Oxidase and Acetylcholinesterase for the Treatment of Alzheimer's Disease
(American Chemical Society, 2019) Kumar, B; Dwivedi, A.R; Sarkar, B; Gupta, S.K; Krishnamurthy, S; Mantha, Anil K; Parkash, Jyoti; Kumar, Vinod
Alzheimer's disease (AD) is a neurodegenerative disorder with multifactorial pathogenesis. Monoamine oxidase (MAO) and acetylcholinesterase enzymes (AChE) are potential targets for the treatment of AD. A total of 15 new propargyl containing 4,6-diphenylpyrimidine derivatives were synthesized and screened for the MAO and AChE inhibition activities along with ROS production inhibition and metal-chelation potential. All the synthesized compounds were found to be selective and potent inhibitors of MAO-A and AChE enzymes at nanomolar concentrations. VB1 was found to be the most potent MAO-A and BuChE inhibitor with IC 50 values of 18.34 ± 0.38 nM and 0.666 ± 0.03 μM, respectively. It also showed potent AChE inhibition with an IC 50 value of 30.46 ± 0.23 nM. Compound VB8 was found to be the most potent AChE inhibitor with an IC 50 value of 9.54 ± 0.07 nM and displayed an IC 50 value of 1010 ± 70.42 nM against the MAO-A isoform. In the cytotoxic studies, these compounds were found to be nontoxic to the human neuroblastoma SH-SY5Y cells even at 25 μM concentration. All the compounds were found to be reversible inhibitors of MAO-A and AChE enzymes. In addition, these compounds also showed good neuroprotective properties against 6-OHDA- and H 2 O 2 -induced neurotoxicity in SH-SY5Y cells. All the compounds accommodate nicely to the hydrophobic cavity of MAO-A and AChE enzymes. In the molecular dynamics simulation studies, both VB1 and VB8 were found to be stable in the respective cavities for 30 ns. Thus, 4,6-diphenylpyrimidine derivatives can act as promising leads in the development of dual-acting inhibitors targeting MAO-A and AChE enzymes for the treatment of Alzheimer's disease. © 2018 American Chemical Society.
Aanchalik upnyas aur dalit vimarsha
(2012) Sen, R.K.