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1.
RSC Adv ; 14(24): 17102-17139, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38808245

RESUMO

Chromones are well known as fundamental structural elements found in numerous natural compounds and medicinal substances. The Schiff bases of chromones have a much wider range of pharmacological applications such as antitumor, antioxidant, anti-HIV, antifungal, anti-inflammatory, and antimicrobial properties. A lot of research has been carried out on chromone-based copper(ii) Schiff-base complexes owing to their role in the organometallic domain and promise as potential bioactive cores. This review article is centered on copper(ii) Schiff-base complexes derived from chromones, highlighting their diverse range of pharmacological applications documented in the past decade, as well as the future research opportunities they offer.

2.
Mol Biol Rep ; 51(1): 600, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689046

RESUMO

Single-cell sequencing was developed as a high-throughput tool to elucidate unusual and transient cell states that are barely visible in the bulk. This technology reveals the evolutionary status of cells and differences between populations, helps to identify unique cell subtypes and states, reveals regulatory relationships between genes, targets and molecular mechanisms in disease processes, tumor heterogeneity, the state of the immune environment, etc. However, the high cost and technical limitations of single-cell sequencing initially prevented its widespread application, but with advances in research, numerous new single-cell sequencing techniques have been discovered, lowering the cost barrier. Many single-cell sequencing platforms and bioinformatics methods have recently become commercially available, allowing researchers to make fascinating observations. They are now increasingly being used in various industries. Several protocols have been discovered in this context and each technique has unique characteristics, capabilities and challenges. This review presents the latest advancements in single-cell transcriptomics technologies. This includes single-cell transcriptomics approaches, workflows and statistical approaches to data processing, as well as the potential advances, applications, opportunities and challenges of single-cell transcriptomics technology. You will also get an overview of the entry points for spatial transcriptomics and multi-omics.


Assuntos
Biologia Computacional , Perfilação da Expressão Gênica , Análise de Célula Única , Transcriptoma , Análise de Célula Única/métodos , Humanos , Perfilação da Expressão Gênica/métodos , Biologia Computacional/métodos , Transcriptoma/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Animais
3.
Top Curr Chem (Cham) ; 382(1): 4, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38296918

RESUMO

Pyrimidine is a pharmacologically important moiety that exhibits diverse biological activities. This review reflects the growing significance of transition metal-catalyzed reactions for the synthesis of pyrimidines (with no discussion being made on the transition metal-catalyzed functionalization of pyrimidines). The effect of different catalysts on the selectivity/yields of pyrimidines and catalyst recyclability (wherever applicable) are described, together with attempts to illustrate the role of the catalyst through mechanisms. Although several methods have been researched for synthesizing this privileged scaffold, there has been a considerable push to expand transition metal-catalyzed, sustainable, efficient and selective synthetic strategies leading to pyrimidines. The aim of the authors with this update (2017-2023) is to drive the designing of new transition metal-mediated protocols for pyrimidine synthesis.


Assuntos
Elementos de Transição , Pirimidinas , Catálise
4.
RSC Adv ; 13(51): 35825-35830, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38090080

RESUMO

The classical Paal-Knorr reaction is a prominent tool that can be adopted under biocompatible conditions covering various γ-dicarbonyls for either chemical biology or drug discovery. Meanwhile, the relatively mild conditions for larger molecules within biological systems have not been employed to obtain N-substituted pyrrole derivatives from simpler chiral amino acids/alcohols. The Clauson-Kaas methodology of a standard two-phase acidic mixture buffered with acetate salts was generally required for the time-consuming catalytic condensation of 2,5-dimethoxytetrahydrofuran and fast removal of pyrrolyl products after formation to inhibit their racemization. To achieve a large amount of tethered pyrrole pendants based on l-phenylalanine to construct bioactive ureas as ASK1 and PI3K inhibitors, one quick and highly efficient protocol was realized in an almost neutral and benign aqueous condition. This protocol proceeds within only 15 minutes at 90 °C, achieving nearly quantitative conversion to the final pyrrolyl product via convenient and facile column-free purification. The detailed mechanistic studies by DFT method proposed a new series involving the pathway by the initiation of a zwitterionic species/intermediate for a subsequently much more efficient self-driven pyrrole-formation. This was inconsistent with the traditional kinetic modelling of ring opening to furnish a carbocation, or the utilization of succinaldehyde/dihydroxytetrahydrofuran as a dialdehyde synthetic equivalent. In addition to the relationally neighbouring intramolecular catalytic effect from the amino acid, the crucial "H-bridge" interplay of water, along with the suggestion of a biomimetic route features similar to the N-glycosylation of carbohydrates, probably indicates the totally different reaction courses. The auto-catalysis ability of l-phenylalanine was also extensively investigated by comparisons on the details relating to l-phenylalaninol.

5.
RSC Adv ; 13(29): 19898-19954, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37404320

RESUMO

Herein, we have summarized the vast array of synthetic processes that have been developed for the synthesis of C-glycopyranosyl aldehydes and diverse C-glycoconjugates derived from them by covering the literature reported from 1979 to 2023. Notwithstanding its challenging chemistry, C-glycosides are considered stable pharmacophores and are used as important bioactive molecules. The discussed synthetic methodologies to access C-glycopyranosyl aldehydes take advantage of seven key intermediates, viz. allene, thiazole, dithiane, cyanide, alkene, and nitromethane. Furthermore, the integration of complex C-glycoconjugates derived from varied C-glycopyranosyl aldehydes involves nucleophilic addition/substitution, reduction, condensation, oxidation, cyclo condensation, coupling, and Wittig reactions. In this review, we have categorized the synthesis of C-glycopyranosyl aldehydes and C-glycoconjugates on the basis of the methodology used for their synthesis and on types of C-glycoconjugates, respectively.

6.
Fitoterapia ; 168: 105554, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37270161

RESUMO

Infectious diseases have remained a burgeoning cause of death and disability since long. Staphylococcus aureus (S. aureus) is a severe bacterial pathogen causing nosocomial and community infections. It exhibits widespread resistance to antibiotics posing a significant threat to their efficacy. For combating this challenge, different strategies may include modifying existing antibiotics, developing new antibacterial agents, and combining treatments with resistance mechanism inhibitors. Resistance in S. aureus occurs through horizontal gene transfer or chromosomal mutations. Acquisition mechanisms involve enzymatic modification, efflux, target bypass, and drug displacement. Mutations can impact drug targets, activate efflux pumps, or alter cell wall composition to impede drug access. Overcoming S. aureus resistance requires innovative approaches to preserve antibiotic effectiveness. The present study involves the virtual screening of phytochemicals of diverse chemical classes from Zinc database against the antibiotic resistant targets of S. aureus like ß-Lactamase, Penicillin Binding Protein 2a (PBP2a), Dihydrofolate reductase (DHFR), DNA gyrase, Multidrug ABC transporter SAV1866, Undecaprenyl diphosphate synthase (UPPS), etc. Thymol, eugenol, gallic acid, l-ascorbic acid, curcumin, berberine and quercetin were identified as potential molecules based on their docking score, binding interactions. These molecules were further analyzed for the ADMET and drug likeness properties using pkCSM, SwissADME and Qikprop tools. Further in vitro evaluation of these molecules against antibiotic-resistant strains of S. aureus, both alone and in combination with antibiotics revealed significant findings. Curcumin demonstrated the lowest MIC values (31.25-62.5 µg/ml) when tested individually. Thymol, berberine, and quercetin displayed MIC values within the range of 125-250 µg/ml, while eugenol and gallic acid exhibited MIC values ranging from 500 to 1000 µg/ml. Notably, thymol exhibited potent synergy with all four antibiotics against clinical isolates of S. aureus, with Fractional inhibitory concentration index (FICI) values consistently below 0.5, highlighting its exceptional antibacterial activity, especially in combination with amoxicillin.


Assuntos
Berberina , Curcumina , Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus , Timol , Eugenol/metabolismo , Curcumina/metabolismo , Quercetina/farmacologia , Quercetina/metabolismo , Berberina/metabolismo , Estrutura Molecular , Antibacterianos/farmacologia , Antibacterianos/química , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana
7.
Crit Rev Oncol Hematol ; 183: 103915, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36702424

RESUMO

In breast cancer, mAbs can play multifunctional roles like targeting cancer cells, sometimes directly attacking them, helping in locating and delivering therapeutic drugs to targets, inhibiting cell growth and blocking immune system inhibitors, etc. Monoclonal antibodies are also one of the important successful treatment strategies especially against HER2 but they have not been explored much for other types of breast cancers especially in triple negative breast cancers. Monoclonal antibodies impact the feasibility of antigen specificity, bispecific and trispecific mAbs have opened new doors for more targeted specific efficacy. Monoclonal antibodies can be used diversly and with efficacy as compared to other methods of treatment thus maining it a suitable candidate for breast cancer treatment. However, mAbs treatment also causes various side effects such as fever, trembling, fatigue, headache and muscle pain, nausea/vomiting, difficulty in breathing, rashes and bleeding. Understanding the pros and cons of this strategy, we have explored in this review, the current and future potential capabilities of monoclonal antibodies with respect to diagnosis and treatment of breast cancer. DATA AVAILABILITY: Not applicable.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Anticorpos Monoclonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Proliferação de Células
8.
J Polym Environ ; 31(3): 999-1018, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36405816

RESUMO

Combating triple-negative breast cancer (TNBC) is still a problem, despite the development of numerous drug delivery approaches. Mucin1 (MUC1), a glycoprotein linked to chemo-resistance and progressive malignancy, is unregulated in TNBC. GO-201, a MUC1 peptide inhibitor that impairs MUC1 activity, promotes necrotic cell death by binding to the MUC1-C unit. The current study deals with the synthesis and development of a novel nano-formulation (DM-PEG-PCL NPs) comprising of polyethylene glycol-polycaprolactone (PEG-PCL) polymer loaded with MUC1 inhibitor and an effective anticancer drug, doxorubicin (DOX). The DOX and MUC1 loaded nanoparticles were fully characterized, and their different physicochemical properties, viz. size, shape, surface charge, entrapment efficiencies, release behavior, etc., were determined. With IC50 values of 5.8 and 2.4 nm on breast cancer cell lines, accordingly, and a combination index (CI) of < 1.0, DM-PEG-PCL NPs displayed enhanced toxicity towards breast cancer cells (MCF-7 and MDA-MB-231) than DOX-PEG-PCL and MUC1i-PEG-PCL nanoparticles. Fluorescence microscopy analysis revealed DOX localization in the nucleus and MUC1 inhibitor in the mitochondria. Further, DM-PEG-PCL NPs treated breast cancer cells showed increased mitochondrial damage with enhancement in caspase-3 expression and reduction in Bcl-2 expression.In vivo evaluation using Ehrlich Ascites Carcinoma bearing mice explicitly stated that DM-PEG-PCL NPs therapy minimized tumor growth relative to control treatment. Further, acute toxicity studies did not reveal any adverse effects on organs and their functions, as no mortalities were observed. The current research reports for the first time the synergistic approach of combination entrapment of a clinical chemotherapeutic (DOX) and an anticancer peptide (MUC1 inhibitor) encased in a diblock PEG-PCL copolymer. Incorporating both DOX and MUC1 inhibitors in PEG-PCL NPs in the designed nanoformulation has provided chances and insights for treating triple-negative breast tumors. Our controlled delivery technology is biodegradable, non-toxic, and anti-multidrug-resistant. In addition, this tailored smart nanoformulation has been particularly effective in the therapy of triple-negative breast cancer. Supplementary Information: The online version contains supplementary material available at 10.1007/s10924-022-02654-4.

9.
Life Sci ; 311(Pt A): 121140, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36347324

RESUMO

AIMS: Development of novel medical countermeasures (MCMs) against acute radiation syndrome (ARS) and the associated lethality involves protection from and/or mitigation of radiation-induced hematopoietic injury, a critical clinical component of ARS. We earlier identified the molecule 7,8-diacetoxy-4-methylthiocoumarin (DAMTC) as a potent mitigator of hematopoietic injury and mortality in C57BL/6 mice when administered 24 h following total body irradiation (TBI). In the present study, we investigated mechanisms and functional relevance of immune modulation by DAMTC during the mitigation of hematopoietic injury. MAIN METHODS: C57BL/6 mice were subjected to TBI doses of 3 and 7.6Gy; administered DAMTC intra-peritoneally 24 h post TBI. Isolation, characterization, intra-cellular cytokine analysis of myeloid cells from bone marrow and spleen accompanied by flow cytometric determination and characterization of B-lymphocytes, serum isolation from peripheral blood and cytokine analysis. KEY FINDINGS: Results showed that DAMTC induced stimulation of pro-inflammatory myeloid subsets in the bone marrow and spleen of TBI mice. Further, it promoted a favorable transition from Th2 to Th1 immunity, triggered humoral immunity, and activated an intricately balanced inflammatory response that appear to contribute to immune-modulation. SIGNIFICANCE: Thus, the present study shows that immune-modulation maybe one of the contributing factors for the mitigation of hematopoietic injury by DAMTC and underscores its efficacy as a potent mitigator of hematopoietic injury that merits to be developed further as a novel MCM to combat H-ARS.


Assuntos
Lesões por Radiação , Camundongos , Animais , Camundongos Endogâmicos C57BL , Irradiação Corporal Total , Medula Óssea/efeitos da radiação , Citocinas
10.
Curr Drug Targets ; 23(2): 116-125, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34551694

RESUMO

Fungal infections have shown an upsurge in recent decades, which is mainly because of the increasing number of immunocompromised patients and the occurrence of invasive candidiasis has been found to be 7-15 fold greater than that of invasive aspergillosis. The genus Candida comprises more than 150 distinct species, however, only a few of them are found to be pathogenic to humans. Mortality rates of Candida species are found to be around 45% and the reasons for this intensified mortality are inefficient diagnostic techniques and unfitting initial treatment strategies. There are only a few antifungal drug classes that are employed for the remedy of invasive fungal infections. which include azoles, polyenes, echinocandins, and pyrimidine analogs. During the last 2-3 decades, the usage of antifungal drugs has increased several folds due to which the reports of escalating antifungal drug resistance have also been recorded. The resistance is mostly to the triazole- based compounds. Due to the occurrence of antifungal drug resistance, the success rates of treatment have been reduced as well as major changes have been observed in the frequency of fungal infections. In this review, we have summarized the major molecular mechanisms for the development of antifungal drug resistance.


Assuntos
Candida , Micoses , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Farmacorresistência Fúngica , Equinocandinas/farmacologia , Equinocandinas/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Micoses/tratamento farmacológico
11.
Cancer Rep (Hoboken) ; 5(12): e1326, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34472223

RESUMO

BACKGROUND: Calreticulin (CRT), an endoplasmic reticulum-resident protein generally overexpressed in cancer cells, is associated with radiation resistance. CRT shows higher transacetylase activity, as shown by us earlier, in the presence of the polyphenolic acetates (like 7, 8-diacetoxy-4-methylcoumarin, DAMC) and modifies the activity of a number of proteins, thereby influencing cell signaling. AIM: To investigate the relationship between CRT expression and radiation response in a human glioma cell line and to evaluate the radiomodifying effects of DAMC. METHODS AND RESULTS: Studies were carried out in an established human glioma cell line (BMG-1) and its isogenic clone overexpressing CRT (CROE, CRT-overexpressing cells) by analyzing clonogenic survival, cell proliferation, micronuclei analysis, and protein levels by Western blotting as parameters of responses. CRT overexpression conferred resistance against radiation-induced cell death in CROE cells (D37  = 7.35 Gy, D10  = 12.6 Gy and D0  = 7.25 Gy) as compared to BMG-1 cells (D37  = 5.70 Gy, D10  = 9.2 Gy and D0  = 5.6 Gy). A lower level of radiation-induced micronuclei formation observed in CROE cells suggested that reduced induction and/or enhanced DNA repair partly contributed to the enhanced radioresistance. Consistent with this suggestion, we noted that CRT-mediated radioresistance was coupled with enhanced grp78 level and reduced P53 activation-mediated prodeath signaling, while no changes were noted in acetylation of histone H4. DAMC-enhanced radiation-induced delayed (secondary) apoptosis, which was higher in CROE cells. CONCLUSION: CRT overexpression confers resistance against radiation-induced death of human glioma cells, which can be overcome by the polyphenolic acetate DAMC.


Assuntos
Acetatos , Calreticulina , Cumarínicos , Glioma , Polifenóis , Tolerância a Radiação , Radiossensibilizantes , Humanos , Acetatos/farmacologia , Calreticulina/genética , Calreticulina/metabolismo , Linhagem Celular , Glioma/tratamento farmacológico , Glioma/metabolismo , Polifenóis/farmacologia , Cumarínicos/farmacologia , Radiossensibilizantes/farmacologia , Tolerância a Radiação/efeitos dos fármacos
13.
Molecules ; 26(16)2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34443388

RESUMO

The purpose of this study was to examine the free radical scavenging and antioxidant activities of ellagic acid (EA) and ellagic acid peracetate (EAPA) by measuring their reactions with the radicals, 2,2-diphenyl-1-picrylhydrazyl and galvinoxyl using EPR spectroscopy. We have also evaluated the influence of EA and EAPA on the ROS production in L-6 myoblasts and rat liver microsomal lipid peroxidation catalyzed by NADPH. The results obtained clearly indicated that EA has tremendous ability to scavenge free radicals, even at concentration of 1 µM. Interestingly even in the absence of esterase, EAPA, the acetylated product of EA, was also found to be a good scavenger but at a relatively slower rate. Kinetic studies revealed that both EA and EAPA have ability to scavenge free radicals at the concentrations of 1 µM over extended periods of time. In cellular systems, EA and EAPA were found to have similar potentials for the inhibition of ROS production in L-6 myoblasts and NADPH-dependent catalyzed microsomal lipid peroxidation.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica , Ácido Elágico/análogos & derivados , Ácido Elágico/farmacologia , Sequestradores de Radicais Livres/farmacologia , Ácido Peracético/análogos & derivados , Animais , Cinética , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Ácido Peracético/farmacologia , Ratos
14.
Biochim Biophys Acta Gen Subj ; 1865(9): 129933, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34023445

RESUMO

BACKGROUND: A natural product analog, 3-(4-nitrophenyl)-7H-furo[3,2-g]chromen-7-one, which is a nitrophenyl psoralen (NPP) was found to be an effective inhibitor of botulinum neurotoxin type A (BoNT/A). METHODS: In this work, we performed enzyme inhibition kinetics and employed biochemical techniques such as isothermal calorimetry (ITC) and fluorescence spectroscopy as well as molecular modeling to examine the kinetics and binding mechanism of NPP inhibitor with BoNT/A LC. RESULTS: Studies of inhibition mechanism and binding dynamics of NPP to BoNT/A light chain (BoNT/A LC) showed that NPP is a mixed type inhibitor for the zinc endopeptidase activity, implying that at least part of the inhibitor-enzyme binding site may be different from the substrate-enzyme binding site. By using biochemical techniques, we demonstrated NPP forms a stable complex with BoNT/A LC. These observations were confirmed by Molecular Dynamics (MD) simulation, which demonstrates that NPP binds to the site near the active site. CONCLUSION: The NPP binding interferes with BoNT/A LC binding to the SNAP-25, hence, inhibits its cleavage. Based on these results, we propose a modified strategy for designing a molecule to enhance the efficiency of the inhibition against the neurotoxic effect of BoNT. GENERAL SIGNIFICANCE: Insights into the interactions of NPP with BoNT/A LC using biochemical and computational approaches will aid in the future development of effective countermeasures and better pharmacological strategies against botulism.


Assuntos
Toxinas Botulínicas Tipo A/antagonistas & inibidores , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Ficusina/farmacologia , Toxinas Botulínicas Tipo A/metabolismo , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Ficusina/síntese química , Ficusina/química , Cinética , Simulação de Dinâmica Molecular
15.
3 Biotech ; 11(3): 113, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33585151

RESUMO

In silico-docking studies from previous work have suggested that Lys-206 and lys-207 of calreticulin (CR) play a pivotal key role in its well-established transacetylation activity. To experimentally validate this prediction, we introduced three mutations at lysine residues of P-domain of CR: K → A, P mut-1 (K -206, -209), P mut-2 (K -206, -207) and P mut-3 (K -207, -209) and analyzed their immunoreactivity and acetylation potential. The clones of wild-type P-domain (P wt ) and three mutated P-domain (P mut-1, P mut-2 and P mut-3) were expressed in pTrcHis C vector and the recombinant P wt , P mut-1 , P mut-2 and P mut-3 proteins were purified by Ni-NTA affinity chromatography. Screening of the transacylase activity (TAase) by the Glutathione S Transferase (GST) assay revealed that the TAase activity was associated with the P wt and P mut-1 while P mut-2 and P mut-3 did not show any activity. The immune-reactivity to anti-lysine antibody was also retained only by the P mut-1 in which the Lys-207 was intact. Retention of the TAase activity and immunoreactivity of P mut-1 with mutations introduced at Lys-206, Lys-209, while its loss with a mutation at Lys-207 residue indicated that lysine-207 of P-domain constitutes the active site residue controlling TAase activity. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02659-1.

16.
Sci Rep ; 11(1): 3771, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33580143

RESUMO

Five novel pyrazolylnucleosides have been evaluated theoretically for their corrosion inhibition efficiency on the Cu(111) surface in acidic media. DFT calculations were carried out to exhibit the intrinsic properties such as lowest unoccupied (ELUMO) and highest occupied (EHOMO) molecular orbital energies, as well as energy gap (∆E), chemical hardness (η), chemical softness (σ), electronegativity (χ), electrophilicity (ω) and nucleophilicity (ε). The theoretical FT-IR spectra were recorded to indicate the presence of the specific bonds in the studied molecules. The surface interactions between the inhibitor molecules and the metal surface were investigated using molecular dynamics simulations and Monte Carlo (MC) simulations. As a result, we have found that the inhibitor pyrazolylnucleosides 5a-e have strong interactions with Cu(111) surface, and therefore have excellent predictive inhibition power against copper corrosion.

17.
Org Biomol Chem ; 18(40): 7987-8033, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33000845

RESUMO

From the viewpoint of meeting the current green chemistry challenges in chemical synthesis, there is a need to disseminate how the cocktail of acylation and activation can play a pivotal role in affording bioactive acylated products comprising substituted ketone motifs in fewer reaction steps, with higher atom-economy and improved selectivity. In recent years, a significant number of articles employing the title compounds "aldehydes" as magnificent acylation surrogates which are less toxic and widely applicable have been published. This review sheds light on the compounds use for selective acylation of arene, heteroarene and alkyl (sp3, sp2 and sp) C-H bonds by proficient utilization of the C-H activation strategy. Critical insights into selective acylation of diverse moieties for the synthesis of bioactive compounds are presented in this review that will enable academic and industrial researchers to understand the mechanistic aspects involved and fruitfully employ these strategies in designing novel molecules.

18.
Protein Pept Lett ; 27(8): 736-743, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32133945

RESUMO

BACKGROUND: The semi-synthetic acetoxycoumarins are known to acetylate proteins using novel enzymatic Calreticulin Transacetylase (CRTAase) system in cells. However, the nonenzymatic protein acetylation by polyphenolic acetates is not known. OBJECTIVE: To investigate the ability of 7-acetoxy-4-methyl coumarin (7-AMC) to acetylate proteins non-enzymatically in the test tube. METHODS: We incubated 7-AMC with BSA and analyzed the protein acetylation using Western blot technique. Further, BSA induced biophysical changes in the spectroscopic properties of 7-AMC was analyzed using Fluorescence spectroscopy. RESULTS: Using pan anti-acetyl lysine antibody, herein we demonstrate that 7-AMC acetylates Bovine Serum Albumin (BSA) in time and concentration dependent manner in the absence of any enzyme. 7-AMC is a relatively less fluorescent molecule compared to the parental compound, 7- hydroxy-4-methylcoumarin (7-HMC), however the fluorescence of 7-AMC increased by two fold on incubation with BSA, depending on the time of incubation and concentration of BSA. Analysis of the reaction mixture of 7-AMC and BSA after filtration revealed that the increased fluorescence is associated with the compound of lower molecular weight in the filtrate and not residual BSA, suggesting that the less fluorescent 7-AMC undergoes self-hydrolysis in the presence of protein to give highly fluorescent parental molecule 7-HMC and acetate ion in polar solvent (phosphate buffered saline, PBS). The protein augmented conversion of 7-AMC to 7-HMC was found to be linearly related to the protein concentration. CONCLUSION: Thus protein acetylation induced by 7-AMC could also be non-enzymatic in nature and this molecule can be exploited for quantification of proteins.


Assuntos
Cumarínicos/química , Soroalbumina Bovina/química , Acetilação , Animais , Bovinos
19.
Drug Discov Today ; 25(4): 781-786, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32062010

RESUMO

Total-body exposure to ionizing radiation (TBI) results in life-threatening acute radiation syndrome (ARS), which encompasses hematopoietic and gastrointestinal (GI) injuries and results in dose-dependent morbidity and mortality. Management of ARS warrants the deployment of effective medical countermeasure agents (MCM) that protect against and/or mitigate lethal radiation injury. The polyphenolic acetate (PA) 7,8-diacetoxy-4-methylthiocoumarin (DAMTC) has been identified as a potential MCM against ARS by virtue of it mitigating the lethal effects of TBI in C57BL/6 mice. Herein, we describe current evidence, including mechanistic aspects, for the use of PAs as MCMs against ARS and provide perspectives for their further development as approved drugs for the mitigation of ARS.


Assuntos
Síndrome Aguda da Radiação/prevenção & controle , Cumarínicos/farmacologia , Protetores contra Radiação/farmacologia , Animais , Modelos Animais de Doenças , Desenvolvimento de Medicamentos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Polifenóis/farmacologia , Lesões Experimentais por Radiação/prevenção & controle
20.
Curr Drug Targets ; 21(4): 365-373, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31549952

RESUMO

The existence of the multi-drug resistant (MDR) pathogenic fungus, Candida auris came to light in 2009. This particular organism is capable of causing nosocomial infections in immunecompromised persons. This pathogen is associated with consistent candidemia with high mortality rate and presents a serious global health threat. Whole genome sequence (WGS) investigation detected powerful phylogeographic Candida auris genotypes which are specialized to particular geological areas indicating dissemination of particular genotype among provinces. Furthermore, this organism frequently exhibits multidrug-resistance and displays an unusual sensitivity profile. Identification techniques that are commercialized to test Candida auris often show inconsistent results and this misidentification leads to treatment failure which complicates the management of candidiasis. Till date, Candida auris has been progressively recorded from several countries and therefore its preventive control measures are paramount to interrupt its transmission. In this review, we discussed prevalence, biology, drug-resistance phenomena, virulence factors and management of Candida auris infections.


Assuntos
Candida/genética , Candida/patogenicidade , Candidíase/tratamento farmacológico , Candidíase/epidemiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Adolescente , Adulto , Idoso , Antifúngicos/farmacologia , Candida/citologia , Candida/efeitos dos fármacos , Candidíase/microbiologia , Candidíase/prevenção & controle , Criança , Pré-Escolar , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Farmacorresistência Fúngica Múltipla/genética , Farmacorresistência Fúngica Múltipla/fisiologia , Feminino , Saúde Global , Humanos , Lactente , Recém-Nascido , Controle de Infecções , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores de Virulência , Adulto Jovem
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