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1.
Bioorg Chem ; 104: 104326, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33142431

RESUMO

SARS-CoV-2 (COVID-19) epidemic has created an unprecedented medical and economic crisis all over the world. SARS-CoV-2 is found to have more contagious character as compared to MERS-CoV and is spreading in a very fast manner all around the globe. It has affected over 31 million people all over the world till date. This virus shares around 80% of genome similarity with SARS-CoV. In this perspective, we have explored three major targets namely; SARS-CoV-2 spike (S) protein, RNA dependent RNA polymerase, and 3CL or Mpro Protease for the inhibition of SARS-CoV-2. These targets have attracted attention of the medicinal chemists working on computer-aided drug design in developing new small molecules that might inhibit these targets for combating COVID-19 disease. Moreover, we have compared the similarity of these target proteins with earlier reported coronavirus (SARS-CoV). We have observed that both the coronaviruses share around 80% similarity in their amino acid sequence. The key amino acid interactions which can play a crucial role in designing new small molecule inhibitors against COVID-19 have been reported in this perspective. Authors believe that this study will help the medicinal chemists to understand the key amino acids essential for interactions at the active site of target proteins in SARS-CoV-2, based on their similarity with earlier reported viruses. In this review, we have also described the lead molecules under various clinical trials for their efficacy against COVID-19.

2.
Nat Prod Res ; 33(8): 1147-1157, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29770710

RESUMO

First total synthesis of carpatamide-A 7a, cytotoxic arylamine derivative isolated from marine derived Streptomyces sp., was achieved in twelve steps with overall yield of 24% with seven longest linear steps. In the penultimate step, dienoic acid 13 and an amino-phenylpropionic acid methyl ester core 21 were coupled to synthesize methylated derivativative of carpatamide-A 22 followed by demethylation of the intermediate with BBr3 to accomplish carpatamide-A 7a. Both precursors 13 and 21 were synthesized from readily available starting materials i.e. isovaleraldehyde 8 and 2, 4-dihydroxy benzaldehyde 14.


Assuntos
Aminas/síntese química , Aminas/química , Ésteres/química , Estrutura Molecular , Streptomyces/química
3.
Org Biomol Chem ; 15(23): 4992-4999, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28567464

RESUMO

A novel and simple approach to the synthesis of sulfonylureas has been reported. It involved the reaction of various amines with diphenyl carbonate to yield the corresponding carbamates, which subsequently reacted with different sulphonamides to produce different sulfonylureas in excellent yields. The first reaction of diphenyl carbonate with amines was carried out in aqueous : organic (H2O : THF, 90 : 10) medium at room temperature to produce carbamates that paved a straightforward route to sulfonylureas after reaction with sulfonamides. The above process avoided traditional multistep protocols and the use of hazardous, irritant, toxic and moisture sensitive reagents such as phosgene, isocyanates and/or chloroformates.

4.
AAPS PharmSciTech ; 18(1): 138-146, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-26902373

RESUMO

The objective of this study comprises of developing novel co-spray dried rifampicin phospholipid lipospheres (SDRPL) to investigate its influence on rifampicin solubility and oral bioavailability. Solid-state techniques were employed to characterize the liposphere formulation. SDRPL solubility was determined in distilled water. BACTEC 460TB System was employed to evaluate SDRPL antimycobacterial activity. The oral bioavailability of the lipospheres was evaluated in Sprague Dawley rats. Lipospheres exhibited amorphous, smooth spherical morphology with a significant increase (p < 0.001) in solubility of SDRPL (2:1), 350.9 ± 23 versus 105.1 ± 12 µg/ml and SDRPL (1:1) 306.4 ± 20 versus 105.1 ± 12 µg/ml in comparison to rifampicin (RMP). SDRPL exhibited enhanced activity against Mycobacterium tuberculosis, H37Rv strain, with over twofolds less minimum inhibitory concentration (MIC) than the free drug. Lipospheres exhibited higher peak plasma concentration (109.92 ± 25 versus 54.31 ± 18 µg/ml), faster T max (two versus four hours), and enhanced area under the curve (AUC0-∞) (406.92 ± 18 versus 147.72 ± 15 µg h/L) in comparison to pure RMP. Thus, SDRPL represents a promising carrier system exhibiting enhanced antimycobacterial activity and oral bioavailability of rifampicin.


Assuntos
Fosfolipídeos/química , Rifampina/administração & dosagem , Rifampina/química , Administração Oral , Animais , Antibióticos Antituberculose/administração & dosagem , Antibióticos Antituberculose/química , Antibióticos Antituberculose/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Química Farmacêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Masculino , Mycobacterium tuberculosis/efeitos dos fármacos , Fosfolipídeos/administração & dosagem , Fosfolipídeos/farmacocinética , Ratos , Ratos Sprague-Dawley , Rifampina/farmacocinética , Solubilidade
5.
Drug Deliv ; 23(4): 1453-68, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26878325

RESUMO

The purpose of this study was to develop folic acid functionalized long-circulating co-encapsulated docetaxel (DTX) and curcumin (CRM) solid lipid nanoparticles (F-DC-SLN) to improve the pharmacokinetic and efficacy of DTX therapy. F-DC-SLN was prepared by hot melt-emulsification method and optimized by face centered-central composite design (FC-CCD). The SLN was characterized in terms of size and size distribution, drug entrapment efficiency and release profile. The cytotoxicity and cell uptake of the SLN formulations were evaluated in MCF-7 and MDA-MB-231 cell lines. The in vivo pharmacokinetic and biodistribution were studied in Wistar rats. F-DC-SLN exhibited 247.5 ± 3.40 nm particle size with 73.88 ± 1.08% entrapment efficiency and zeta potential of 14.53 ± 3.6 mV. Transmission electron microscopy (TEM) revealed spherical morphology of the SLN. Fluorescence microscopy confirmed the targeting efficacy of F-DC-SLN in MCF-7 cells. F-DC-SLN exhibited a significant increase in area under the curve (594.21 ± 64.34 versus 39.05 ± 7.41 µg/mL h) and mean residence time (31.14 ± 19.94 versus 7.24 ± 4.51 h) in comparison to Taxotere®. In addition, decreased DTX accumulation from F-DC-SLN in the heart and kidney in comparison to Taxotere may avoid to toxicity these vital organs. In conclusion, the F-DC-SLN improved the efficacy and pharmacokinetic profile of DTX exhibiting enhanced potential in optimizing breast cancer therapy.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Curcumina/administração & dosagem , Curcumina/farmacocinética , Portadores de Fármacos/química , Ácido Fólico/química , Lipídeos/química , Nanopartículas/química , Taxoides/administração & dosagem , Taxoides/farmacocinética , Animais , Antineoplásicos/química , Neoplasias da Mama/química , Linhagem Celular Tumoral , Química Farmacêutica , Curcumina/química , Docetaxel , Portadores de Fármacos/metabolismo , Liberação Controlada de Fármacos , Feminino , Humanos , Células MCF-7 , Ratos , Ratos Wistar , Taxoides/química , Distribuição Tecidual
6.
Pharm Dev Technol ; 21(5): 554-62, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26024238

RESUMO

CONTEXT: Although several formulation strategies have been developed for the treatment of psoriasis, there is an unmet need for optimization of its therapy. OBJECTIVE: The objective was to develop a nanogel composed of methotrexate (MTX)-loaded nanostructured lipid carrier (MTX-NLC) and to evaluate its potential in imiquimod-induced psoriasis model to ameliorate symptoms of psoriasis. MATERIALS AND METHODS: MTX-NLC nanogel was prepared by hot-homogenization method and optimized by Design of Experiments. Particle size, polydispersity index (PDI) and entrapment efficiency were selected as the critical quality attributes. Antipsoriatic potential of MTX-NLC nanogel was evaluated by Psoriatic Area and Severity Index (PASI) score and histopathological examination in the imiquimod-induced psoriasis model. RESULTS AND DISCUSSION: Optimized MTX-NLC exhibited particle size of 278 ± 10 nm, PDI of 0.231 ± 0.05 and EE of 22.29 ± 1.23%. At the end of 48 h, MTX-NLC gel exhibited slow and prolonged release of MTX (47.32 ± 0.94% versus 94.23 ± 0.79%) compared to MTX gel. Furthermore, it significantly reduced the PASI score with recovery of normalcy of the mice's skin, while the MTX gel exhibited signs of hyper and parakeratosis at the end of the study. CONCLUSION: The developed MTX-NLC gel formulation can be a promising alternative to existing MTX formulation in treating psoriasis.


Assuntos
Metotrexato/administração & dosagem , Metotrexato/química , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polietilenoimina/administração & dosagem , Polietilenoimina/química , Psoríase/tratamento farmacológico , Absorção Cutânea/efeitos dos fármacos , Administração Tópica , Animais , Química Farmacêutica , Avaliação Pré-Clínica de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Liberação Controlada de Fármacos/fisiologia , Metotrexato/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Nanogéis , Polietilenoglicóis/metabolismo , Polietilenoimina/metabolismo , Psoríase/metabolismo , Psoríase/patologia , Distribuição Aleatória , Absorção Cutânea/fisiologia , Resultado do Tratamento
7.
Mol Divers ; 19(4): 855-70, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25894361

RESUMO

Thiazolidinone derivatives have been found to exhibit a wide range of pharmacological activities. 2-Thiazolylimino-5-benzylidene-thiazolidin-4-one derivatives show antibacterial activity in in vitro tests which are comparable to marketed drugs. However, the target for this scaffold remains yet to be identified. In our work, we identified seven putative targets for this scaffold using web servers such as DRAR-CPI, PharmMapper, and TarFisDock and databases such as BindingDB and ChEMBL. Each of these servers used different algorithms and scoring functions for protein target identification. Further, these targets are substantiated by molecular docking analysis. Based on the docking studies, scaffold 2-thiazolylimino-5-benzylidene-thiazolidin-4-one is observed to exhibit affinity against diverse targets, particularly, towards COX-2, acetylcholinesterase, aldose reductase, and thyroid hormone receptor alpha. This study describes an initial probability that these proteins may be targeted by this scaffold.


Assuntos
Proteínas/antagonistas & inibidores , Tiazolidinas/farmacologia , Acetilcolinesterase/metabolismo , Aldeído Redutase/metabolismo , Algoritmos , Ciclo-Oxigenase 2/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Proteínas/metabolismo , Relação Estrutura-Atividade , Tiazolidinas/química , Receptores alfa dos Hormônios Tireóideos/metabolismo
8.
Bioorg Chem ; 54: 1-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24681308

RESUMO

Enoxaparin (ENX) is one of the most widely prescribed low molecular weight heparin inprophylaxis and treatment of venous thromboembolism. In this study, Enoxaparin-PEG conjugate (P-ENX) was synthesized from Enoxaparin and polyethylene glycol (PEG) and evaluated for its potential for extended duration of action. The esterification of the carboxyl groups of the drug moiety with the hydroxyl groups of mPEG-2000 was done by employing carbodiimide coupling chemistry. P-ENX conjugate was purified by dialysis and characterized by Fourier transform infrared spectroscopy (FTIR), Proton-Nuclear magnetic resonance ((1)H NMR) and matrix-assisted laser desorption/ionization (MALDI) mass analysis techniques. FTIR analysis revealed frequency of the carbonyl group in accord with ester linkage formation between the drug and the PEG moiety. (1)H NMR of the conjugate showed significant change in the chemical shift further indicative of ENX and PEG chemical interaction. In MALDI spectra, small peaks at 12,907 and 16,137 m/z confirmed the probability of conjugation of ENX and PEG. P-ENX exhibited considerable enhancement in anti-Xa activity (by three-folds) in comparison to free ENX. Further, an increase in AUC (over four-folds) was observed in P-ENX. Thus, PEGylation of ENX is a novel approach for extended and enhanced activity of ENX with a potential for decreased dosing frequency.


Assuntos
Enoxaparina/farmacologia , Inibidores do Fator Xa/farmacologia , Fator Xa/metabolismo , Polietilenoglicóis/química , Animais , Enoxaparina/administração & dosagem , Enoxaparina/sangue , Inibidores do Fator Xa/administração & dosagem , Inibidores do Fator Xa/sangue , Feminino , Estrutura Molecular , Peso Molecular , Polietilenoglicóis/administração & dosagem , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Fatores de Tempo
9.
Int J Pharm ; 460(1-2): 220-7, 2014 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-24188983

RESUMO

To enhance the oral bioavailability of rifampicin (RMP), the newly emerging phospholipid complexation technique was employed. Rifampicin-phospholipid complex (RMP-PC) was prepared by solvent-evaporation method. Infrared spectroscopy (IR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and hot stage microscopy (HSM) analysis were employed to confirm the formation of phospholipid complex. The results reveal hydrogen bond formation and electrostatic interaction between RMP and phospholipid molecule play an important role in the formation of RMP-PC without the formation of a new compound. In comparison with the physical mixture and RMP, solubility studies indicated an enhancement in the aqueous solubility of RMP-PC. Stability studies of RMP-PC in presence of isoniazid showed a remarkable improvement of the stability of the phospholipid complex in comparison to free RMP. Oral bioavailability of RMP-PC was evaluated in Sprague-Dawley (SD) rats and plasma rifampicin estimated by LCMS. RMP-PC exhibited higher peak plasma concentration (54.3 vs. 48.5 µg/mL), increased AUC0-∞ (472.4 vs. 147.71 5.812 ± 0.49 µg h/mL), increased T1/2 (8.3 vs. 1.5h) when compared to free RMP implying improved bioavailability of the drug. This enhancement can be attributed to the improvement of the aqueous solubility of rifampicin-phospholipid complex. Hence, phospholipid complexation holds a promising potential for increasing oral bioavailability of poorly water soluble drugs.


Assuntos
Antibióticos Antituberculose/química , Antibióticos Antituberculose/farmacocinética , Fosfolipídeos/química , Fosfolipídeos/farmacocinética , Rifampina/química , Rifampina/farmacocinética , Animais , Antibióticos Antituberculose/sangue , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Química Farmacêutica , Estabilidade de Medicamentos , Masculino , Microscopia Eletrônica de Varredura , Difração de Pó , Ratos , Ratos Sprague-Dawley , Rifampina/sangue , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
10.
Toxicol Rep ; 1: 885-893, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-28962300

RESUMO

The aim of the study was to investigate the protective effect of isoniazid-curcumin conjugate (INH-CRM) in INH-induced hepatic injury by biochemical analysis and histology examination of liver in Wistar rats. The biochemical analysis included determination of the levels of plasma cholesterol, triglycerides (TG), albumin content, and lipid peroxidation (MDA). INH-CRM administration resulted in a significant decrease in plasma cholesterol, TG, and MDA levels in the liver tissue homogenate with an elevation in albumin level indicating its hepatoprotective activity. Histology of the liver further confirmed the reduction in hepatic injury. The hepatoprotective with INH-CRM can be attributed to the antioxidant activity of curcumin. The conjugate probably stabilizes the curcumin molecule, preventing its presystemic metabolism thereby enhancing its bioavailability and therefore, its hepatoprotective activity. Thus, the novel INH-CRM has the potential to alleviate INH-induced liver toxicity in antitubercular treatment.

11.
J Org Chem ; 63(3): 808-811, 1998 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-11672077

RESUMO

Hydrolysis of 2,2,2-trifluoroethanesulfonyl chloride (1) is shown to take place by way of the sulfene (CF(3)CH=SO(2)), formed by (a) an irreversible E1cB process over the pH range 1.8-5 with water acting as the carbanion-forming base in the lower pH range and hydroxide anion at higher pH, and (b) a reversible E1cB reaction in dilute acid.

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