School Of Basic And Applied Sciences

Permanent URI for this communityhttps://kr.cup.edu.in/handle/32116/17

Browse

End date: 2020Subject: search.filters.subject.Synthesis

Search Results

Now showing 1 - 10 of 14
  • Thumbnail Image
    Item
    Tetrazoles as anticancer agents: A review on synthetic strategies, mechanism of action and SAR studies
    (Elsevier, 2020) Dhiman, N; Kaur, K; Jaitak, Vikas
    Cancer is a leading cause of death worldwide. Even after the availability of numerous drugs and treatments in the market, scientists and researchers are focusing on new therapies because of their resistance and toxicity issues. The newly synthesized drug candidates are able to demonstrate in vitro activity but are unable to reach clinical trials due to their rapid metabolism and low bioavailability. Therefore there is an imperative requisite to expand novel anticancer negotiators with tremendous activity as well as in vivo efficacy. Tetrazole is a promising pharmacophore which is metabolically more stable and acts as a bioisosteric analogue for many functional groups. Tetrazole fragment is often castoff with other pharmacophores in the expansion of novel anticancer drugs. This is the first systematic review that emphasizes on contemporary strategies used for the inclusion of tetrazole moiety, mechanistic targets along with comprehensive structural activity relationship studies to provide perspective into the rational design of high-efficiency tetrazole-based anticancer drug candidates. - 2020 Elsevier Ltd
  • Thumbnail Image
    Item
    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.
  • Thumbnail Image
    Item
    Synthesis And Antiproliferative Activity Of Pyrazole-Based Heterocycles
    (Central University of Punjab, 2018) Pandey, Vishakha; Kumar, Raj
    Among the various heterocyclic compounds pyrazole and its derivatives have occupied wide range of biological and pharmacological activities. These were observed for their modes of function in the inhibition of topoisomerase and DNA repair. DNA topoisomerases usually modify DNA topology by their ability to break and reseals both its strands. Which were leads to DNA replication, transcription processes. It helps as a vital targets for numerous chemotherapeutic agents. The potency of topoisomerase inhibitors looks to be diminishing due to drug resistance and lack of efficacy. Thus, after long glimpsing the current scenario was made in order to develop topoisomerase inhibitors with completely new scaffold or alteration or modification in the existing scaffold. We herein report design and synthesis of pyrazole based compounds as topoisomerase inhibitors. The synthetics were evaluated for their in vitro anticancer activity against MDAMB 231 breast cancer cell line.
  • Thumbnail Image
    Item
    Synthesis, Characterization and Biological Evaluation of 5-(2- Nitrophenyl)-1H-Pyrazole Derivatives as Putative Antiproliferative Agents
    (Central University of Punjab, 2018) Saini, Geetika; Kumar, Raj
    Pyrazoles are known to exhibit various biological activities like antibacterial, antiprotozoal, anticonvulsant, analgesic, anti-inflammatory, antiviral and antiproliferative. An attempt has been made to synthesize substituted pyrazoles. Their antiproliferative activity was determined by performing MTT assay on MDA-MB 231 cell line (breast cancer). The compounds were further docked into topoisomerase 1 and 2
  • Thumbnail Image
    Item
    Synethesis and biochemical screening of novel non-purine based xanthine oxidase inhibitors
    (Central University of Punjab, 2013) Kumar, Deependra; Kumar, Raj
    Xanthine oxidase (XO), or xanthine oxidoreductase (XOR), is a complex molybdoflavoenzyme which, in humans, is recognized as the terminal enzyme of purine catabolism, catalysing the hydroxylation of purines to uric acid, overproduction of which usually leads to a pathological condition called hyperuricemia and gout. XO inhibitors (XOI) are proved to be promising urate lowering agents. Purine based XOI (allopurinol) however, are associated with various lethal side effects like hypersensitivity syndrome (Stevens Johnson syndrome and Tissue Epidermal Necrolysis), bone marrow depression, rash etc. On the other hand non-purine based XOI (febuxostat) are found to be safer and effective antihyperuricemic and antigout agents. Present investigation describes synthesis, characterization of some non-purine based compounds and their evaluation for xanthine oxidase inhibitory activity
  • Thumbnail Image
    Item
    Polydopamine films change their physicochemical and antimicrobial properties with a change in reaction conditions
    (Royal Society of Chemistry, 2018) Patel, Khushbu; Singh, Nimisha; Yadav, Jyoti; Nayak, Jyotsna M.; Sahoo, Suban K; Lata, Jeevan; Chand, Duni; Kumar, Shashank; Kumar, Rajender
    The morphology and physicochemical properties of polydopamine are not totally inherent and undergo changes with differing reaction conditions like the choice of solvent used for polymerization. The polymerisation of dopamine to polydopamine carried out in different solvents like sodium hydroxide, sodium bicarbonate, PBS and Tris leads to polydopamine with exceptionally different morphological and physicochemical features with each solvent. Additionally, the different physicochemical characteristics and morphologies bestow the polymer films with different extents of antimicrobial activity. Moreover, the findings supported by chemical evidence from X-ray photoelectron spectroscopy reveal that higher antibacterial activities were obtained against E. coli and S. aureus with polydopamine films prepared by Tris and NaOH solvent induced polymerization. The antibacterial activity observed in saline was found to be higher than that in PBS medium for both E. coli and S. aureus. The higher antibacterial activity of polydopamine films prepared in Tris and NaOH solvents was attributed to the covalent incorporation of -OH groups on the surface provided by nucleophilic Tris and NaOH solvents during the polymerisation process. The distinct physicochemical and morphological changes were supported by the results from contact angle measurements, FE-SEM, EDAX, AFM, and XPS analysis. The present finding provides insight into the different chemistry, morphologies and properties of the designed polydopamine films with controlled antibacterial/antifouling properties. Additionally, new insights into the mechanism of formation, physicochemical changes in morphology and properties of polydopamine coatings were revealed. ? the Owner Societies.
  • Thumbnail Image
    Item
    Chitosan-supported copper as an efficient and recyclable heterogeneous catalyst for A3/decarboxylative A3-coupling reaction
    (Elsevier Ltd, 2018) Kaur, Pavneet; Kumar, Bhupinder; Kumar, Vinod; Kumar, Rakesh
    Chitosan-supported copper (chit@copper) based heterogeneous catalysts have been explored for A3-coupling and decarboxylative A3-coupling. The developed protocol employs low catalyst loading, solventless condition and easy work-up for the synthesis of diversely substituted propargylamines. More importantly, the catalyst could be recovered and reused without any significant loss in the activity. This offer huge advantages as recyclability issues are rarely addressed in decarboxylative A3-coupling. Leaching studies were carried out using AAS and ICPMS analysis. It is envisaged that chit@copper catalysts can have potential applications in terms of efficiency and recyclability in the emerging area of decarboxylative C?H bond activation/functionalization strategies. ? 2018 Elsevier Ltd
  • Thumbnail Image
    Item
    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.
  • Thumbnail Image
    Item
    Pyrazoloquinazolines: Synthetic strategies and bioactivities
    (2015) Garg, Mansi; Chauhan, Monika; Singh, Pankaj Kumar; Singh, Pankaj Kumar; Alex, Jimi Marin; Kumar, Raj
    Numerous N-heterocycles are indisputably evidenced to exhibit myriad biological activities. In the recent past, attempts made to condense the various heterocycles have resulted in derivatives possessing better bioactivities. Among many such condensed heterocycles, pyrazoloquinazolines have managed to hold the attention of many researchers, owing to the broad spectrum of activities they portray. This review is the first of its kind to congregate the various pyrazoloquinazolines reported until now and categorizes these structurally isomeric classes into eleven different groups based on the fusion pattern of the ring such as [1,5-c], [5,1-b], [4,3-h], etc. Furthermore, this review is a concerted effort to highlight design, synthetic strategies as well as biological activities of each class of this condensed heterocycle. Structure-activity relationship studies and in silico approaches wherever reported have also been discussed. In addition, manuscript also offers scope for design, synthesis and generation of libraries of unreported classes of pyrazoloquinazolines for the biological evaluation. Copyright ? 2014 Elsevier Masson SAS. All rights reserved.
  • Thumbnail Image
    Item
    Microwave-assisted synthesis of pyrazolo[1,5-c]quinazolines and their derivatives
    (Elsevier, 2014) Kumar, Deependra; Kumar, Raj
    Microwave accelerated and expedited cyclocondensation reactions of 2-(3-aryl-1H-pyrazol-5-yl)anilines (4) with diverse aryl aldehydes/triethyl orthoformate in water/MeCN (route D) and internal cyclocondensation and aromatization of 5-(2-aminophenyl)-4,5-dihydro-3-arylpyrazole-1-carbaldehyde (7) under MeOH (route E) for the synthesis of a series of pyrazolo[1,5-c]quinazolines and their derivatives (1a–1q) are reported.