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1.
J Biomol Struct Dyn ; : 1-14, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38423128

RESUMO

In an endeavour to improve the anti-cancer activity of betulinic acid (BA), a series of C-30 derivatives were envisaged and synthesized with a novel synthetic approach. All the derivatives were evaluated for cytotoxic activity by MTT assay against six different human cancer cell lines: prostate (PC3), lung (A549), human hepatocellular carcinoma (HepG2), human leukemia (Molt-4), pancreatic (Panc-1) and breast (MCF-7). The data revealed that compound 16 was observed most promising cytotoxic agent with IC50 values of 7.43 µM, 9.1 µM, and 9.64 µM against A549, MCF-7, and PC3 cancer cell lines respectively. A further mechanistic study confirmed compound 16 showed significant cell death by arresting the cell cycle in the G1 phase and inducing apoptosis in A549 cells.Communicated by Ramaswamy H. Sarma.

2.
Anticancer Agents Med Chem ; 23(7): 747-764, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35959907

RESUMO

Bakuchiol is a meroterpene natural product distributed in various plants. It possesses several biological activities particularly anticancer. A large number of analogs have been prepared by various researchers by targeting several positions such as phenolic -OH, ethenyl and isopropylidene groups present in the bakuchiol to develop potent therapeutic agents with improved pharmaceutical properties. The present review describes the isolation, organic synthetic schemes, chromatographic study, and biological activities of bakuchiol reported till date. Further, the review also provides an insight into the skin care effects of bakuchiol and structure-activity relationship studies of reported derivatives. Moreover, the biosynthetic pathway of bakuchiol has also been described. All the articles published on bakuchiol revealed that bakuchiol and its analogs possess a remarkable potential for the development of potent anticancer and several other therapeutic agents. The reported synthetic schemes can be utilized for the industrial production of bakuchiol. Finally, we believe that this review will provide important information to the researchers interested in the chemistry and biology of Bakuchiol.


Assuntos
Biologia , Fenóis , Humanos , Fenóis/farmacologia , Fenóis/química
3.
Chem Biodivers ; 19(9): e202200560, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35962990

RESUMO

Nineteen heterocyclic chalcones were synthesized from 4-acetyl-5-methylquinolylpyrazole and heteroaryl (imidazole, pyrazole, thiophene, indole and triazole) aldehydes and were screened in vitro using four tumor cell lines for their cytotoxic capability and for antimicrobial activity. The chalcone 5b exhibited the highest activity with IC50 values 2.14 µM against colon (HCT-116) and 5.0 µM, against prostate (PC-3) cancer cell lines and also displayed good activity against fungal strain (A. niger) with MIC value 9.1 µM. The chalcones 5q and 5p displayed good activity against bacterial strains (S. aureus) having MIC value 2.6 µM and fungal strain (C. albicans) having MIC value 5.4 µM, respectively. The molecular docking outcome revealed that the synthesized heterocyclic chalcones demonstrated hydrogen bond, hydrophobic and electrostatic interactions with their respective biochemical targets.


Assuntos
Anti-Infecciosos , Antineoplásicos , Chalcona , Chalconas , Aldeídos , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Candida albicans , Chalconas/química , Imidazóis , Indóis , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirazóis/química , Staphylococcus aureus , Relação Estrutura-Atividade , Tiofenos , Triazóis
4.
Arch Microbiol ; 204(8): 472, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35819545

RESUMO

UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) is an essential cytosolic enzyme in the biosynthesis of peptidoglycan. It becomes a potential bacterial target for screening promising antibacterial compounds as it is associated with the early phases of peptidoglycan production. MurA enzyme is conserved and necessary for bacterial viability with no mammalian homolog, which is a well-proven therapeutic research target. The present study reports the natural compounds from Boswellia serrata targeting the MurA enzyme. The identified inhibitors against MurA Escherichia coli (E. coli): ß-boswellic acid (IC50 33.65 µM), Acetyl-ß-boswellic acid (IC50 30.17 µM), and Acetyl-11-keto-ß-boswellic acid (IC50 37.67 µM). Inhibitors showed a fourfold decrease in IC50 values on pre-incubation with substrate-UDP-N-acetyl-glucosamine (UDP-GlcNAc). Mode-of-inhibition studies revealed their uncompetitive nature with both the substrates. Although these boswellic acids have been explored for their pharmacological potential, this is the first study reporting these compounds' E. coli MurA inhibiting potential.


Assuntos
Alquil e Aril Transferases , Peptidoglicano , Acetilglucosamina , Escherichia coli/genética , Triterpenos , Difosfato de Uridina
5.
Appl Microbiol Biotechnol ; 105(9): 3611-3623, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33860835

RESUMO

Bacterial cell has always been an attractive target for anti-infective drug discovery. MurA (UDP-N-acetylglucosamine enolpyruvyl transferase) enzyme of Escherichia coli (E.coli) is crucial for peptidoglycan biosynthetic pathway, as it is involved in the early stages of bacterial cell wall biosynthesis. In the present study we aim to identify novel chemical structures targeting the MurA enzyme. For screening purpose, we used in silico approach (pharmacophore based strategy) for 52,026 library compounds (Chembridge, Chemdiv and in house synthetics) which resulted in identification of 50 compounds. These compounds were screened in vitro against MurA enzyme and release of inorganic phosphate (Pi) was estimated. Two compounds (IN00152 and IN00156) were found to inhibit MurA enzyme > 70% in primary screening and IC50 of 14.03 to 32.30 µM respectively. These two hits were further evaluated for their mode of inhibition studies and whole-cell activity where we observed 2-4 folds increase in activity in presence of Permeabilizer EDTA (Ethylenediaminetetraacetic acid). Combination studies were also performed with known antibiotics in presence of EDTA. Hits are reported for the first time against this target and our report also support the use of OM permeabilizer in combination with antibacterial compounds to address the permeability and efficacy issue. These lead hits can be further optimized for drug discovery. KEY POINTS: • Emerging Gram negative resistant strains is a matter of concern. • Need for new screening strategies to cope with drying up antibiotics pipeline. • Outer membrane permeabilizers could be useful to improve potency of molecules to reach its target.


Assuntos
Alquil e Aril Transferases , Escherichia coli , Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Peptidoglicano
6.
Drug Dev Res ; 80(7): 948-957, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31318064

RESUMO

Diclofenac is one of the world's largest selling nonsteroidal anti-inflammatory drugs. The major concerns related to oral diclofenac therapy are gastrointestinal and cardiovascular side effects for which explicitly emphasis has been given to use it at lowest effective dose for the shortest duration. On the other hand, IS01957 has been designed under the purview of anti-inflammatory drug and bioavailability enhancer. IS01957 have dual action on inflammation and nociception with acceptable safety profile. In the quest for a suitable combination with improved therapeutic efficacy and better tolerability, pharmacodynamic and pharmacokinetic interaction studies were performed for diclofenac with or without IS01957 in mice model. Results showed that IS01957 enhanced both anti-inflammatory effect and plasma concentration of diclofenac upon concomitant oral administration. These interesting results steered to enumerate the possible role of IS01957 towards diclofenac pharmacokinetics through a panel of mechanistic investigations: (a) BCRP dependent ATPase activity was markedly interfered by IS01957; (b) IS01957 increased the intestinal permeability of diclofenac in the single pass in-situ perfusion model; (c) IS01957 inhibited the CYP2C9 catalyzed diclofenac 4-hydroxylation in human liver microsomes. Immunoblotting results suggest that diclofenac action was improved significantly in the presence of IS01957 involving MAPK pathways. Finally acute gastric damage study showed that IS01957 in combination with diclofenac was better to improve the desired PGE2 level as compare to alone. In nutshell, IS01957 have potential to augment the efficacy of diclofenac through pharmacokinetic modulation. Further investigations are required for dose reduction of diclofenac to combat its liabilities before going into clinical setting.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Diclofenaco/farmacocinética , Morfolinas/farmacologia , Propionatos/farmacologia , Adenosina Trifosfatases/antagonistas & inibidores , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Citocromo P-450 CYP2C9/metabolismo , Diclofenaco/administração & dosagem , Dinoprostona/metabolismo , Interações Medicamentosas , Sinergismo Farmacológico , Feminino , Mucosa Gástrica/metabolismo , Hidroxilação/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Microssomos Hepáticos/metabolismo , Morfolinas/administração & dosagem , Permeabilidade/efeitos dos fármacos , Ratos
7.
Bioorg Med Chem ; 27(2): 343-353, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30552006

RESUMO

Inhibitors for NorA efflux pump of Staphylococcus aureus have attracted the attention of many researchers towards the discovery and development of novel efflux pump inhibitors (EPIs). In an attempt to find specific potent inhibitors of NorA efflux pump of S. aureus, a total of 15 amino acid conjugates of 3-(1-chloro-3,4-dihydronaphthalen-2-yl)acrylic acid (4-18) were synthesized using a simple convenient synthetic approach and bioevaluated against NorA efflux pump. Two compounds 7 and 8 (each having MEC of 1.56 µg/mL) were found to restore the activity of ciprofloxacin through reduction of the MIC elucidated by comparing the ethidium bromide efflux in dose dependent manner in addition to ethidium bromide efflux inhibition and accumulation study using NorA overexpressing strain SA-1199B. Most potent compounds among these were able to restore the antibacterial activity of ciprofloxacin completely against SA-1199B. Structure activity relationship (SAR) studies and docking study of potent compounds 7 and 8 could elucidate the structural requirements necessary for interaction with the NorA efflux pumps. On the whole, compounds 7 and 8 have ability to reverse the NorA efflux mediated resistance and could be further optimized for development of potent efflux pump inhibitors.


Assuntos
Acrilamidas/farmacologia , Antibacterianos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Naftalenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Acrilamidas/síntese química , Acrilamidas/química , Antibacterianos/síntese química , Antibacterianos/química , Proteínas de Bactérias/química , Sítios de Ligação , Ciprofloxacina/farmacologia , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Estrutura Molecular , Proteínas Associadas à Resistência a Múltiplos Medicamentos/química , Naftalenos/síntese química , Naftalenos/química , Relação Estrutura-Atividade
8.
Int J Antimicrob Agents ; 53(1): 49-53, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30267759

RESUMO

Current long duration treatment options and the emergence of drug resistance in tuberculosis (TB) have led to renewed interest in discovery of novel anti-tubercular agents or the scaffolds exhibiting enhanced efficacy with current anti-TB drugs. Herein, dinactin, a potent bioactive macrotetrolide isolated from Streptomyces puniceus AS13, was evaluated against Mycobacterium tuberculosis H37Rv and other susceptible and drug-resistant clinical isolates of M. tuberculosis. In vitro pharmacological assays showed that dinactin is bactericidal against laboratory standard strain M. tuberculosis H37Rv (minimum inhibitory concentration [MIC] 1 µg/mL and minimum bactericidal concentration [MBC] 4 µg/mL). Dinactin also retained its activity against various clinical isolates, including multidrug-resistant strains of M. tuberculosis. Whole cell interaction assays with standard first- and second-line anti-TB drugs showed the synergistic interaction of dinactin with rifampicin or amikacin, reflecting its suitability for use in combination regimens. The killing kinetics studies of dinactin against M. tuberculosis H37Rv revealed that it has strong concentration-dependent anti-TB activity that is also dependent on time. The kill curve also showed dynamic killing capacity of dinactin as it exhibited bactericidal potential at all concentrations tested. Kill curve data demonstrated that dinactin, like isoniazid, exerts its strong tuberculocidal activity within the first two days of exposure. This evidence strongly supports further evaluation of dinactin as a new option in the treatment of TB.


Assuntos
Antituberculosos/farmacologia , Macrolídeos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Macrolídeos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular
9.
Eur J Med Chem ; 145: 511-523, 2018 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-29335212

RESUMO

A library of 28 analogs of bavachinin including aliphatic and aromatic ethers, epoxide, chalcone, oxime, semicarbazide, oxime ether and triazole derivatives have been synthesized and evaluated for cytotoxicity against four different human cancer cell lines. Bio-evaluation studies exhibited better cytotoxic profile for many analogs compare to bavachinin. Best results were observed for a 1,2,3-triazole analog (17i) with IC50 values 7.72, 16.08, 7.13 and 11.67 µM against lung (A549), prostate (PC-3), colon (HCT-116) and breast (MCF-7) cancer cell lines respectively. This analog showed three and four fold improvement in cytotoxicity against HCT-116 and A549 cell lines than parent molecule (1). Structure activity relationship (SAR) study for all synthesized analogs was carried out. Further, mechanistic study of the lead molecule (17i) revealed that it inhibits colony formation and in vitro migration of human colon cancer cells (HCT-116). Also, it induced the morphological changes and mediated the apoptotic cell death of HCT-116 cells with perturbance in mitochondrial membrane potential (MMP) and PARP cleavage.


Assuntos
Antineoplásicos/farmacologia , Flavonoides/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Flavonoides/síntese química , Flavonoides/química , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
10.
Eur J Med Chem ; 135: 517-530, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28500966

RESUMO

Different benzylidene derivatives (15a-o and 16a-o) of betulinic acid were designed and synthesized in an effort to develop potent anticancer agents. All the synthesized derivatives along with betulinic acid were evaluated for cytotoxicity against a panel of five different human cancer cell lines A-549 (Lung), PC-3 (Prostate), HCT 116 (Colon), MCF-7 (Breast) and MIA PaCa-2 (Pancreatic) using SRB assay. Pharmacological results showed that compounds 15b, 15c, 15i, 15k, 16a-c and 16l were found to have promising cytotoxic profile against various cancer cell lines tested (IC50 1-2 µM). Best results were observed for compound 16c with IC50 values 1.5, 1.6, 1.36, 3.5 and 3.2 µM against A-549, PC-3, HCT 116, MCF-7 and MIA PaCa-2 cell lines, respectively. Mechanistic study of compound 16c revealed that it inhibits the colony formation and restrict the migration in HCT 116 cells in vitro. It also induces growth arrest with characterized morphological changes and loss of mitochondrial membrane potential (MMP) in a concentration dependent manner.


Assuntos
Antineoplásicos/farmacologia , Compostos de Benzilideno/farmacologia , Citotoxinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Compostos de Benzilideno/síntese química , Compostos de Benzilideno/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citotoxinas/síntese química , Citotoxinas/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
11.
Steroids ; 123: 1-12, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28435038

RESUMO

In an endeavour to develop potent anti-tumor agents from betulinic acid (BA), a series of C-28 derived 1,2,3-triazolyl derivatives were designed and synthesized by employing Cu(I) catalyzed Huisgen 1,3-dipolar cycloaddition reaction. All the derivatives were evaluated for cytotoxic activity by MTT assay against five different human cancer cell lines: lung (A549), colon (HCT116), prostate (PC3), pancreatic (MIA PaCa-2) and breast (T47D). The data revealed that compounds 11c, 11d, 11g, 11h and 13a possess most promising cytotoxic potential. The compound 11h was one of the most active compounds, with IC50 values in the range of 4-6µM against all the five cancer cell lines. The results of this study suggested that derivatives with free -OH (11c, 11d and 11g) and free -COOH (11h and 13a) substitutions in the triazole moiety introduced at the C-28 position significantly improved the anti-tumor activity and may be the favourable position to synthesize potent anticancer leads from BA. Introduction of a non polar alkyl groups at C-28 position (10, 12 and 14) resulted in the significant loss of the activity. Further, DAPI staining, ROS generation and wound healing experiments revealed that compound 11h induces apoptosis in HCT-116 cells.


Assuntos
Alcinos/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Azidas/química , Triterpenos/síntese química , Triterpenos/farmacologia , Antineoplásicos/química , Catálise , Núcleo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cobre/química , Reação de Cicloadição , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Humanos , Concentração Inibidora 50 , Triterpenos Pentacíclicos , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Triterpenos/química , Ácido Betulínico
12.
Eur J Med Chem ; 127: 1047-1058, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27847171

RESUMO

A new library of 20 compounds from α-santonin was synthesized and tested against Con-A induced T-cell proliferation and LPS-induced B-cell proliferation via MTT assay. The study resulted in the identification of potent immunosuppressant molecules, which were further screened along with α-santonin for Tumor Necrosis Factor Alpha (TNF-α) inhibitory activity. One of the molecules (7) at 10 µM showed equipotency to that of dexamethasone (1 µM conc.) used as a standard. Structure activity relationships of the synthesized compounds along with our earlier reported α-santonin derivatives have been studied. Inferences from the modifications carried out at all the three sites of α-santonin have been elaborated. Computational study of the active compounds shows TNF-α protein as its preferable target rather than Inosine Monophosphate Dehydrogenase (IMPDH).


Assuntos
Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Santonina/síntese química , Santonina/farmacologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Animais , Linfócitos B/metabolismo , Proliferação de Células/efeitos dos fármacos , Técnicas de Química Sintética , IMP Desidrogenase/química , IMP Desidrogenase/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Conformação Proteica , Santonina/química , Santonina/metabolismo , Relação Estrutura-Atividade , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
13.
Medchemcomm ; 8(1): 211-219, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30108707

RESUMO

In continuation of our endeavours to synthesize immunosuppressive agents from α-santonin, we report herein the design and synthesis of a new series of α-santonin derived O-aryl/aliphatic ether, ester and amide analogs and the evaluation of their immunosuppressive activities. The in vitro studies led to several analogs with significant immunosuppressive effects by inhibiting ConA and LPS stimulated T- and B-cell proliferation in a dose dependent manner. The more significant compounds 4d, 4e, 4f, 4h, 6a and 6b displayed potent inhibitory activity on the mitogen-induced T- and B-cell proliferation in comparison to α-santonin 1. Compound 4e displayed stupendous in vitro immunosuppressive effects with ∼80% suppression of B and ∼75% suppression of T lymphocyte proliferation, respectively. The in vivo investigation on BALB/c mice revealed that non-cytotoxic compound 4e suppresses both humoral and cellular immunity.

14.
Phytochemistry ; 132: 102-108, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27745695

RESUMO

Five new xanthones, named coxanthones A-E (1-5), together with 21 known secondary metabolites (6-26) that include seven xanthones, five flavonoids, two steroids and seven triterpenoids were isolated from the chemically unexplored whole plant Codonopsis ovata. The structures of new metabolites were elucidated by HRMS, interpretation of NMR spectra and other spectroscopic techniques. The absolute configuration of the stereogenic centre of coxanthone B (2) was determined by electronic circular dichroism (ECD) spectroscopy. This is the first report of xanthones from the genus Codonopsis. All isolated metabolites were evaluated for cytotoxic activity by SRB assay against six human cancer cell lines A549 (lung), PC-3 (prostate), HCT-116 (colon), MCF-7 (breast), SF-295 (CNS), and MDAMB-435 (melanoma). Among the new compounds, coxanthone B (2) exhibited significant inhibitory activity against SF-295 and MDAMB-435 with IC50 values of 7.0 and 15.0 µM, respectively. Coxanthone A (1) displayed cytotoxicity against A549 cell line at IC50 value of 22.5 µM. Cytotoxic activity of 1-hydroxy-3,5-dimethoxyxanthone (7), swertiperenine (9) and 1,7,8-trihydroxy-3-methoxyxanthone (10) are reported here first time that exhibited the IC50 values of 3.0, 5.0 and 21.0 µM against A549, MDAMB-435, and A549 cell lines, respectively. Kaempferol (13) showed most potent cytotoxic activity with an IC50 values in the 1.0-2.3 µM range against all tested cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Codonopsis/química , Flavonoides/isolamento & purificação , Esteroides/isolamento & purificação , Esteroides/farmacologia , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Xantonas/isolamento & purificação , Xantonas/farmacologia , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Flavonoides/síntese química , Flavonoides/farmacologia , Células HCT116 , Humanos , Concentração Inibidora 50 , Masculino , Ressonância Magnética Nuclear Biomolecular , Esteroides/química , Triterpenos/química , Xantonas/química
15.
Eur J Med Chem ; 120: 160-9, 2016 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-27191613

RESUMO

A new series of α-santonin derived acetyl santonous acid 1,2,3-triazole derivatives were synthesised using Huisgen 1,3-dipolar cyclo-addition reaction (click chemistry approach) and evaluated for their in vitro inhibition activity on concanavalin A (ConA) induced T cell proliferation and lipopolysaccharide (LPS) induced B cell proliferation. Among the synthesised series, compounds 2-10 and 19 exhibited significant inhibition against ConA and LPS stimulated T-cell and B-cell proliferation in a dose dependent manner. More significantly compounds 4, 9-10 and 19 exhibited potent inhibition activity with remarkably lower cytotoxicity on the mitogen-induced T cell and B cell proliferation at 1 µM concentration. The compound 6 displayed potent immunosuppressive effects with ∼89% against LPS induced B-cell and ∼83% against ConA stimulated T-cell proliferation at 100 µM concentration without cytotoxicity. Compound 10 was more selective against B cell proliferation and exhibited 81% and 69% suppression at 100 and 1 µM concentration respectively. The present study led to the identification of several santonin analogs with reduced cytotoxicity and strong inhibition activity against the cell proliferation induced by the mitogens.


Assuntos
Linfócitos B/citologia , Proliferação de Células/efeitos dos fármacos , Santonina/química , Linfócitos T/citologia , Triazóis/síntese química , Sobrevivência Celular/efeitos dos fármacos , Química Click , Relação Dose-Resposta a Droga , Humanos , Imunossupressores , Triazóis/química , Triazóis/farmacologia
16.
Eur J Med Chem ; 108: 104-116, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26629862

RESUMO

In an attempt to arrive at more potent cytotoxic agent than the bioactive natural product betulinic acid, influence of small structural modifications of its 1, 2, 3 triazole derivatives tethered at C-28 and both C3, C-28 using click chemistry approach has been studied. The chemically characterized triazoles have been screened for in vitro cytotoxicity against four human cancer cell lines HL-60, MiaPaCa-2, PC-3 and A549 which has allowed to identify triazole derivative 28{1N (4-fluoro phenyl)-1H-1, 2, 3-triazol-4-yl} methyloxy betulinic ester having better potency profile than the parent compound with IC50 values in the range of 5-7 µM. It caused disruption of mitochondrial membrane potential, rendered Bcl-2 cleavage, Bax translocation and decrease Bcl-2/Bax ratio. These events are accompanied by activation of caspases -9, -3, which cleave the PARP-1. It also induces caspase-8, which is involved in extrinsic apoptotic pathway. Therefore, it induces apoptosis through both intrinsic and extrinsic pathways in human leukemia HL-60 cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Leucemia/patologia , Triazóis/farmacologia , Triterpenos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Estrutura Molecular , Triterpenos Pentacíclicos , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química , Triterpenos/síntese química , Triterpenos/química , Ácido Betulínico
17.
Mol Carcinog ; 55(5): 964-76, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26013878

RESUMO

In spite of the Betulinic acid (BA) being recognized as anticancerous source; its further use in clinical development is greatly hampered because of its poor pharmacokinetic properties. To circumvent these limitations, we synthesized a PI3K target based library of 18 triazole based derivatives and we identified a C-3 cyano analog of betulinic acid (CBA) with significant cell death effects with 5-7 fold higher potency than BA in various cancers. Importantly, no such report is available demonstrating the involvement of BA or its structural analogs in the modulation of PI3K pathway. Using, human leukemia HL-60 cells as a model, we for the first time report that CBA decreased expression of PI3K p110α, p85α, and pAKT in HL-60. Furthermore, we could find significant depletion of pGSK3ß, cyclin D1 and increased expression of p21/cip, p27/Kip proteins. CBA induced G0/G1 cell cycle arrest, increased sub-G0 DNA fraction and annexin V binding of the cells besides imparting the typical surface features of cell death. Also, this target specific inhibition was associated with mitochondrial apoptosis as was reflected by expression studies of various proteins together with reactive oxygen species generation and decline in mitochondrial trans membrane potential. The apoptotic effectors i.e., caspase 8 and caspase 9 were found to get upregulated besides PI3K associated DNA repair enzyme i.e., PARP cleavage was observed. Thus, our results elucidated that CBA or other BA based small molecules inhibit PI3K/AKT pathway with induction of subsequent cancer cell death which may be useful therapeutic strategy against leukemias and possibly other cancers.


Assuntos
Ciclina D1/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Neoplasias/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Triazóis/farmacologia , Triterpenos/agonistas , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta , Células HL-60 , Humanos , Células MCF-7 , Neoplasias/genética , Triterpenos Pentacíclicos , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Triazóis/síntese química , Triterpenos/farmacologia , Ácido Betulínico
18.
J Sep Sci ; 38(23): 4021-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26412260

RESUMO

Chemical investigation of Cicer microphyllum resulted in the isolation and characterization of eight natural products viz. Stigmasterol, Oleanolic acid-3-acetate, Oleanolic acid, Biochanin A, Genistein, Pratensein, Chrysoeriol, and Luteolin. Herein, we report a novel, accurate, and cost-effective high-performance thin-layer chromatography method for the simultaneous quantification of the isolated natural products on silica-gel 60F254 plates using the solvent system n-hexane/ethyl acetate/formic acid (9.0:6.5:0.8, v/v/v). Natural products were quantified after postchromatographic derivatization with ceric ammonium sulfate. The method was validated as per the International Conference on Harmonization guidelines. All calibration curves showed a good linear relationship (r > 0.9943) within the test range. Precision was assessed by intra- and interday tests with relative standard deviations <1.82%, accuracy validation recovery 98.38-99.57% with relative standard deviations <1.00%. On quantification, Pratensein was a major constituent (0.921%). The screening for cytotoxic activity using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay resulted into identification of Luteolin as potent molecule with IC50 3.5 and 25.6 µg/mL against murine melanoma and human epidermoid carcinoma cell lines, respectively.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia em Camada Delgada , Cicer/química , Extratos Vegetais , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Analítica/economia , Técnicas de Química Analítica/normas , Cromatografia em Camada Delgada/economia , Cromatografia em Camada Delgada/normas , Humanos , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Reprodutibilidade dos Testes
19.
J Pharm Biomed Anal ; 100: 300-308, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25194343

RESUMO

Chemical investigation of Codonopsis ovata resulted in the isolation and identification of ß-sitosterol-3-O-glycoside, luteolin, apigenin, gentiacaulein, swertiaperenine, ß-sitosterol, taraxeryl-3-acetate, and 3ß-acetoxyoleanane-12-one. A rapid, precise, sensitive and validated HPTLC method for simultaneous quantification of these natural products (NPs) was developed on silica-gel 60F254 plate using ternary solvent system, n-hexane:ethyl acetate:formic acid (10.5:3.5:0.43, v/v/v). Markers were quantified after post chromatographic derivatization with cerric ammonium sulfate reagent. The method was validated for accuracy, precision, LOD, LOQ and all calibration curves showed a good linear relationship (r>0.9924) within test range. Precision was evaluated by intra- and inter-day tests with RSDs <2.59%, accuracy validation recovery 92.43-99.50% with RSDs <1.00%. Apigenin was found major component (natural abundance: 1.103%) and ß-sitosterol the least (0.0263%). The NPs displayed antioxidant activity with luteolin exhibiting maximum effect at 1µg/mL concentration (75.9% for DPPH and 43.7% for ABTS) and others at 10 and 25µg/mL, suggesting thereby their apparent potential use for the prevention of free radical induced diseases or as an additive element to food and pharmaceutical industry.


Assuntos
Cromatografia em Camada Delgada/métodos , Codonopsis/metabolismo , Sequestradores de Radicais Livres/análise , Extratos Vegetais/análise , Acetatos/química , Sulfato de Amônio/química , Benzotiazóis/química , Compostos de Bifenilo/química , Calibragem , Formiatos/química , Sequestradores de Radicais Livres/farmacologia , Hexanos/química , Limite de Detecção , Modelos Lineares , Fitoterapia , Picratos/química , Extratos Vegetais/farmacologia , Plantas Medicinais , Padrões de Referência , Reprodutibilidade dos Testes , Sílica Gel/química , Solventes/química , Ácidos Sulfônicos/química
20.
J Sep Sci ; 36(16): 2602-10, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23775831

RESUMO

Betulinic acid (1), betulinic acid-3-acetate (2), 3-acetylbetulinaldehyde (3), oleanolic acid-3-acetate (4), 3-ß-hydroxy-28,19-ß-olenolide (5), and ß-sitosterol (6) were isolated from Platanus orientalis and a high-performance thin-layer chromatography method was developed for their simultaneous quantification. The markers were first derivatized on the chromatogram with ceric ammonium sulfate and then high-performance thin-layer chromatography densitometry was carried out. Chromatographic separation of these markers was carried out on silica gel 60 plates using a ternary solvent system n-hexane/toluene/acetone (6:3.5:1 v/v/v) as a mobile phase. For marker 1, a deuterium (D2) lamp and wavelength of 420 nm was used. A tungsten (W) lamp was used for markers 2 and 3 at 550 nm and for 4-6 at 500 nm. The method was validated for accuracy, precision, LOD, and LOQ. All calibration curves showed a good linear relationship (r > 0.9919). The precision evaluated by an intra- and interday study showed RSDs < 2.51% and accuracy validation recovery between 95.54 and 99.33% with RSDs < 1.55%. The successful application of the validated method showed 1 as the most abundant component (4.63%) and 5 (0.017%) the least. The markers displayed a significant cytotoxic effect against human keratinocyte, mouse melanoma, and human skin epithelial carcinoma cancer cells by using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.


Assuntos
Cromatografia em Camada Delgada/métodos , Magnoliopsida/química , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Neoplasias Cutâneas/tratamento farmacológico , Animais , Biomarcadores/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Camundongos , Neoplasias Cutâneas/fisiopatologia
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