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1.
FEMS Microbiol Lett ; 3712024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38453437

RESUMO

For undergraduate pharmacy students, the first step of antimicrobial stewardship learning objectives is to integrate antimicrobial knowledge from the foundational sciences. We hypothesised that using a multidisciplinary approach including two sessions of tutorials could be relevant in term of students' interest, satisfaction and learning retention time. The evaluation of students' feelings was based on a questionnaire including different dimensions and three focus groups with four students. Quantitative data were analysed with the EPI-INFO 7.2 software and a thematic analysis was implemented for qualitative data by using NVivo 12 software. The evaluation of students' learning concerned both short-time learning retention (STLR) and medium-time learning retention (MTLR), six months after the last session. Overall, 63 students responded to the questionnaire. Most of them appreciated the tutorials according to the different dimensions envisaged. Focus groups confirmed the interest of students for the multidisciplinary approach, interactions with teachers and opportunities of learning transfers. Concurrently, a lack of self-efficacy, low confidence towards the other students, external regulation of motivation and poor autonomy were recorded for some participants. Finally, there was no significant decrease between the scores of the STLR assessment and those of the MTLR assessment (58.5 ± 12.1/100 and 54.4 ± 8.9/100, respectively).


Assuntos
Antibacterianos , Farmácia , Humanos , Aprendizagem , Estudantes , Ira
2.
Bull Cancer ; 110(2S): S88-S96, 2023 Feb.
Artigo em Francês | MEDLINE | ID: mdl-35523598

RESUMO

Since patients require multiple intravenous drugs, drug incompatibilities and drug interactions are frequent during the acute phase following hematopoietic cell transplantation. The risk of drug-drug interactions is increased in patients with several comorbidities. The goal of this workshop was to learn how to mitigate the risks of drug incompatibilities and interactions when their usage is therapeutically warranted. Our focus was on proton pump inhibitors and antiemetic drugs as they are routinely used in hematopoietic transplants and frequently lead to incompatibilities and interactions with other drugs such as immunosuppressives and antimicrobials. Routine procedures in transplantation such as the choice of vascular access devices, the setting of infusion lines, the scheduling of administration of drugs and their dilution volumes can be effective armaments to mitigate the risks of drug incompatibilities and interactions. In addition, a multidisciplinary concertation between clinicians, pharmacists and nurses is a key point in the success of patient's care.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Imunossupressores , Humanos , Comorbidade , Interações Medicamentosas , Transplante de Células-Tronco Hematopoéticas/efeitos adversos
3.
Pharmaceuticals (Basel) ; 14(12)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34959720

RESUMO

5-Azacitidine, a cytidine analogue used as a hypomethylating agent, is one of the main drugs for the treatment of myelodysplastic syndromes (MDSs) and acute myeloid leukemia (AML) in the elderly. However, after administration, it exhibits several limitations, including restricted diffusion and cellular internalization due to its hydrophilicity, and a rapid enzymatic degradation by adenosine deaminase. The aim of this study was to improve the drug cell diffusion and protect it from metabolic degradation via the synthesis of amphiphilic prodrugs and their potential self-assembly. Azacitidine was conjugated to two different omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The carboxylic acid group of the omega-3 fatty acids was effectively conjugated to the amine group of the azacitidine base, yielding two amphiphilic prodrugs. Nanoprecipitation of the obtained prodrugs was performed and self-assemblies were successfully obtained for both prodrugs, with a mean diameter of 190 nm, a polydispersity index below 0.2 and a positive zeta potential. The formation of self-assemblies was confirmed using pyrene as a fluorescent dye, and the critical aggregation concentrations were determined: 400 µM for AzaEPA and 688 µM for AzaDHA. Additionally, the stability of the obtained self-assemblies was studied and after 5 days their final stable arrangement was reached. Additionally, cryo-TEM revealed that the self-assemblies attain a multilamellar vesicle supramolecular structure. Moreover, the obtained self-assemblies presented promising cytotoxicity on a leukemia human cell line, having a low IC50 value, comparable to that of free azacitidine.

4.
Nanoscale Adv ; 3(8): 2157-2179, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36133769

RESUMO

Nucleoside and nucleotide analogs are essential tools in our limited arsenal in the fight against cancer. However, these structures face severe drawbacks such as rapid plasma degradation or hydrophilicity, limiting their clinical application. Here, different aspects of nucleoside and nucleotide analogs have been exposed, while providing their shortcomings. Aiming to improve their fate in the body and combating their drawbacks, two different approaches have been discussed, the prodrug and nanocarrier technologies. Finally, a novel approach called "PUFAylation" based on both the prodrug and nanocarrier technologies has been introduced, promising to be the supreme method to create a novel nucleoside or nucleotide analog based formulation, with enhanced efficacy and highly reduced toxicity.

5.
Curr Pharm Des ; 24(46): 5580-5589, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30727871

RESUMO

BACKGROUND: Among polyphenolic compounds suggested to prevent cardiovascular diseases (CVDs) and to explain the "French paradox", the anthocyanidin delphinidin (Dp) has been reported to support at least partly the vascular beneficial effects of dietary polyphenolic compounds including those from fruits and related products as red wine. It has also been highlighted that Dp interacts directly with the active site of estrogen receptor α (ERα), leading to activation of endothelial NO synthase (eNOS) pathway thus contributing to the prevention of endothelial dysfunction in mice aorta. However, anthocyanidins have very low bioavailability and despite a well described in vitro efficacy, the very high hydrophilicity and physicochemical instability of Dp might explain the lack of in vivo reported effects. OBJECTIVE: The aim of this study was to identify new Dp analogues with increased lipophilicity and vasorelaxation potential by a chemical modulation of its structure and to characterize the signaling pathway notably in relation with ERα signaling and nitric oxide (NO) production. METHOD: OCH3-substituted delphinidin analogues were obtained through the coupling of the corresponding acetophenones with substituted benzaldehydes. Prediction of resorption of the flavylium derivatives was performed with the calculated logP and induction of vasorelaxation was performed by myography on WT and ERαKO mice thoracic aorta rings and compared to Dp. NO production was evaluated in vitro on human primary endothelial cells. RESULTS: Eight Dp analogues were synthesized including four new flavylium derivatives. Two compounds (9 and 11) showed a strong increase of vasorelaxation potential and a theoretically increased bioavailability compared to Dp. Interestingly, 9 and 11 induced increased O2 - or NO endothelial production respectively and revealed a novel NO-dependent ERα-independent relaxation compared to Dp. We suggested that this mechanism may be at least in part supported by the inhibition of vascular cyclic nucleotide phosphodiesterase (PDEs). CONCLUSION: The current study demonstrated that pharmacomodulation of the Dp backbone by replacement of OH groups by OCH3 groups of the A and B rings led to the identification and characterization of two compounds (9 and 11) with enhanced physio-chemical properties that could be associated to higher permeability capability and pharmacological activity for the prevention of CVDs compared to Dp.


Assuntos
Antocianinas/síntese química , Antocianinas/farmacologia , Desenho de Fármacos , Vasodilatadores/síntese química , Vasodilatadores/farmacologia , Animais , Aorta Torácica/efeitos dos fármacos , Receptor alfa de Estrogênio , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Estrutura Molecular , Óxido Nítrico
6.
Molecules ; 22(4)2017 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-28417947

RESUMO

Ethoxidine, a benzo[c]phenanthridine derivative, has been identified as a potent inhibitor of topoisomerase I in cancer cell lines. Our group has reported paradoxical properties of ethoxidine in cellular processes leading to angiogenesis on endothelial cells. Because low concentration ethoxidine is able to favor angiogenesis, the present study aimed to investigate the ability of 10-9 M ethoxidine to modulate neovascularization in a model of mouse hindlimb ischemia. After inducing unilateral hindlimb ischemia, mice were treated for 21 days with glucose 5% or with ethoxidine, to reach plasma concentrations equivalent to 10-9 M. Laser Doppler analysis showed that recovery of blood flow was 1.5 fold higher in ethoxidine-treated mice in comparison with control mice. Furthermore, CD31 staining and angiographic studies confirmed an increase of vascular density in ethoxidine-treated mice. This ethoxidine-induced recovery was associated with an increase of NO production through an enhancement of eNOS phosphorylation on its activator site in skeletal muscle from ischemic hindlimb. Moreover, real-time RT-PCR and western blots have highlighted that ethoxidine has pro-angiogenic properties by inducing a significant enhancement in vegf transcripts and VEGF expression, respectively. These findings suggest that ethoxidine could contribute to favor neovascularization after an ischemic injury by promoting the NO pathway and VEGF expression.


Assuntos
Indutores da Angiogênese/farmacologia , Membro Posterior/irrigação sanguínea , Membro Posterior/efeitos dos fármacos , Isquemia/metabolismo , Óxido Nítrico/metabolismo , Fenantridinas/farmacologia , Indutores da Angiogênese/química , Animais , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Isquemia/tratamento farmacológico , Masculino , Camundongos , Estrutura Molecular , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/metabolismo , Fenantridinas/química , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Pharmaceuticals (Basel) ; 10(1)2017 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-28134835

RESUMO

The GP2A European Conference is a two-day meeting focused on medicinal chemistry and the use of tools to explore all fields of drug discovery and drug design such as molecular modelling, bioorganic chemistry, MS studies, in vitro in vivo assays, and structure activity relationships. Abstracts of keynote lectures, plenary lectures, junior lectures, flash presentations, and posters presented during the meeting are collated in this report.

8.
Pharmaceuticals (Basel) ; 9(1)2015 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-26712767

RESUMO

The European Conference on Therapeutic Targets and Medicinal Chemistry is a new two-day meeting on drug discovery that is focused on therapeutic targets and the use of tools to explore all fields of drug discovery and drug design such as molecular modelling, bioorganic chemistry, NMR studies, fragment screening, in vitro assays, in vivo assays, structure activity relationships, autodisplay. Abstracts of keynote lectures, plenary lectures, junior lectures, flash presentations, and posters presented during the meeting are collected in this report.

9.
Invest New Drugs ; 33(1): 75-85, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25404487

RESUMO

Angiogenesis plays a pivotal role in tumorigenesis and also contributes to the pathogenesis of hematologic malignancies. A number of plant compounds have shown efficacy in preclinical and clinical studies and some of them possess an anti-angiogenic activity. Our present findings report anti-angiogenic activities of ethoxyfagaronine (etxfag), a synthetic derivative of fagaronine. Once determined the non-cytotoxic concentration of etxfag, we showed that the drug inhibits VEGF-induced angiogenesis in a Matrigel™ plug assay and suppresses ex vivo sprouting from VEGF-treated aortic rings. Each feature leading to neovascularization was then investigated and results demonstrate that etxfag prevents VEGF-induced migration and tube formation in human umbilical vein endothelial cells (HUVEC). Moreover, etxfag also suppresses VEGF-induced VEGFR-2 phosphorylation and inhibits FAK phosphorylation at Y-861 as well as focal adhesion complex turnover. Beside these effects, etxfag modifies MT1-MMP localization at the endothelial cell membrane. Finally, immunoprecipitation assay revealed that etxfag decreases VEGF binding to VEGFR-2. As we previously reported that etxfag is able to prevent leukemic cell invasiveness and adhesion to fibronectin, all together our data collectively support the anti-angiogenic activities of etxfag which could represent an additional approach to current anti-cancer therapies.


Assuntos
Inibidores da Angiogênese/farmacologia , Benzofenantridinas/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Aorta/efeitos dos fármacos , Aorta/fisiologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Camundongos Endogâmicos C57BL , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
10.
Mini Rev Med Chem ; 13(9): 1311-26, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23701657

RESUMO

Naturally occurring hydroxamic acid derivatives are biosynthesized by microorganisms (siderophores) and plants (benzoxazinoids). Recent developments in drug discovery have highlighted the numerous biological and pharmacological properties that the hydroxamic acid function may possess, leading to therapeutic applications. These properties may be explained by its ability to chelate metals via the presence of two oxygen atoms. Their pharmacological activities can be divided into three groups. The first concerns the ability of these hydroxamic acid derivatives to scavenge metals (particularly iron), which leads to antioxidant, antimicrobial and metal detoxification activities. The latter is largely used to treat iron overload in patients. The second group of activities is related to their ability to inhibit metallo-enzymes, which gives them a wide range of pharmacological effects: antimicrobial, anti-inflammatory and antitumor. The third group is linked to the capacity of these compounds to generate nitric oxide, which confers hypotensive activity. However, hydroxamates exhibit relatively low stability in vivo, which can be overcome by the synthesis of appropriately designed analogs. For this purpose, many different strategies have been proposed. In this review, we compare and discuss the various synthetic pathways used to obtain the most complex of them, the N-substituted hydroxamic acids. We conclude that among numerous protocols reported so far, the direct N-substitution of hydroxamic acids, the acylation of the appropriate N-O derivative and the direct oxidation of the corresponding amide allow for the synthesis of a wide range of new biologically active compounds.


Assuntos
Ácidos Hidroxâmicos/farmacologia , Animais , Humanos
11.
J Org Chem ; 77(1): 718-24, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22106973

RESUMO

Substitution of an ortho-fluoro or methoxy group in 1- and 2-naphthoic acids furnishing substituted naphthoic acids occurs in good to excellent yields upon reaction with alkyl/vinyl/aryl organolithium and Grignard reagents, in the absence of a metal catalyst without the need to protect the carboxyl (CO(2)H) group. This novel nucleophilic aromatic substitution is presumed to proceed via a precoordination of the organometallic with the substrate, followed by an addition/elimination.


Assuntos
Ácidos Carboxílicos/química , Lítio/química , Magnésio/química , Naftalenos/química , Catálise , Indicadores e Reagentes , Estrutura Molecular , Compostos Organometálicos
12.
Invest New Drugs ; 29(5): 730-41, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20349265

RESUMO

Quaternary benzo[c]phenanthridines such as fagaronine are natural substances which have been reported to exhibit anticancer and anti-leukemic properties. However, the therapeutic use of these molecules is limited due to the high dose required to exhibit anti-tumor activity and subsequent toxicity. In this study, we describe the therapeutic potential of a new derivative of fagaronine, Ethoxyfagaronine (N-methyl-12-ethoxy-2hydroxy-3, 8, 9-trimethoxybenzo[c]-phenanthridiniumchlorhydrate) as an anti-leukemic agent. Cytotoxic activity and cell growth inhibition of Ethoxyfagaronine (Etxfag) was tested on murine L1210 leukemia cells using trypan blue assay and MTT assay. At the concentration of 10(-7) M, Etxfag induced less than 10% of cell death. Etxfag (10(-7) M) was tested on L1210 cell invasiveness using matrigel™ precoated transwell chambers and efficiently reduces the invasive potential of L1210 cells by more than 50% as compared with untreated cells. Western blot and immunofluorescence experiments showed that Etxfag decreased both MT1-MMP expression and activation at the cell surface, decreased plasmin activity by down-regulating u-PAR and uPA expression at the cell surface and increasing PAI-1 secretion in conditioned media. The set of our findings underscore the therapeutic potential of ethoxyfagaronine as a new potential anticancer agent able to prevent leukemic cell dissemination.


Assuntos
Alcaloides/farmacologia , Benzofenantridinas/farmacologia , Regulação para Baixo/efeitos dos fármacos , Leucemia L1210/enzimologia , Leucemia L1210/patologia , Metaloproteinase 14 da Matriz/metabolismo , Ativadores de Plasminogênio/metabolismo , Animais , Aprotinina/farmacologia , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dipeptídeos/farmacologia , Ativação Enzimática/efeitos dos fármacos , Fibrinolisina/metabolismo , Gelatinases/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Leucemia L1210/genética , Metaloproteinase 14 da Matriz/genética , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Invasividade Neoplásica
13.
Carcinogenesis ; 32(3): 286-95, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21135154

RESUMO

Angiogenesis, a critical step in tumorigenesis, is defined by different processes leading to neovascularization. Topoisomerase I (Top I) is the target for some of the most successful anticancer drugs that decrease tumor cell proliferation. Ethoxidine, a benzo[c]phenanthridines derivative, camptothecin analogue, has been identified as a potent inhibitor of Top I in various cancer cell lines. This study was aimed to investigate the impact of ethoxidine on angiogenesis and cellular processes including migration, proliferation and adhesion since these processes play an important role in tumor progression. Ethoxidine was incubated for 24 h at low (10⁻9 M) and high (10⁻5 M) concentrations on two types of human endothelial cells: EaHy.926 and human umbilical endothelial cells. Vascular endothelial growth factor (VEGF, 20 ng/ml) was used as a positive control. Ethoxidine at low concentration increased cell proliferation and migration that was associated with enhanced metalloproteinase 2 expression and activity, whereas high concentration of ethoxidine inhibited all of these effects. The two concentrations of ethoxidine did not affect endothelial cell adhesion. Low concentration of ethoxidine increased VEGF expression and endothelial nitric oxide (NO) synthase expression, NO and superoxide anion productions, whereas high concentration of ethoxidine did not induce any effect. Taken together, the present results highlight paradoxical effects of ethoxidine on angiogenesis depending on the concentration used. This study underscores that in addition to its anti-proliferative properties, ethoxidine may affect the generation of vascular network in tumorigenesis.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Neovascularização Fisiológica , Fenantridinas/farmacologia , Inibidores da Topoisomerase I/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Espectroscopia de Ressonância de Spin Eletrônica , Endotélio Vascular/metabolismo , Citometria de Fluxo , Humanos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Superóxidos/metabolismo , Veias Umbilicais/citologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Med Mycol ; 48 Suppl 1: S98-107, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21067336

RESUMO

Scedosporium apiospermum is an emerging pathogen colonizing the airways of patients with cystic fibrosis (CF). While usually responsible for chronic colonization without clinical signs, this fungus may cause severe and often lethal infections in lung transplant recipients. Early diagnosis of its airway colonization and appropriate treatment are required to eradicate the fungus when a lung transplantation is planned. Here we propose an alternative to mycological examination of sputum samples based on extraction of siderophores by chromatography on Amberlite XAD-4, followed by high performance liquid chromatography analysis of the siderophore extract. Improvement of the extraction procedure was performed in a fractional factorial design which revealed the importance of prior ammonium sulfate precipitation of the proteins, alkalinization of the obtained solution and stirring during extraction. In order to verify the specificity of N(α)-methyl coprogen B for S. apiospermum, the method was applied on culture supernatants of different filamentous fungi colonizing the airways of CF patients, including some aspergilli and Exophiala dermatitidis. N(α)-methyl coprogen B was detected exclusively for species of the S. apiospermum complex. Likewise, sputum samples from colonized and non-colonized CF patients were analyzed, and the siderophore was detected exclusively in three out of the five specimens which were found by culture to contain S. apiospermum. Together these results confirmed N(α)-methyl coprogen B as a marker of the airway colonization by species of the S. apiospermum complex.


Assuntos
Biomarcadores/análise , Fibrose Cística/microbiologia , Ácidos Hidroxâmicos/análise , Pneumopatias Fúngicas/diagnóstico , Sistema Respiratório/microbiologia , Scedosporium/química , Cromatografia Líquida de Alta Pressão , Humanos , Ácidos Hidroxâmicos/química , Pneumopatias Fúngicas/microbiologia , Scedosporium/classificação , Scedosporium/isolamento & purificação , Sideróforos/análise , Sideróforos/química , Especificidade da Espécie , Espectrometria de Massas por Ionização por Electrospray , Escarro/microbiologia
15.
Biometals ; 22(6): 1019-29, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19597710

RESUMO

Scedosporium apiospermum is an emerging pathogen colonizing the airways of patients with cystic fibrosis and causing severe infections in immunocompromised hosts. In order to improve our knowledge on the pathogenic mechanisms of this fungus, we investigated the production of siderophores. Cultivation on CAS medium and specific assays for different classes of siderophores suggested the secretion of hydroxamates. A maximal production was obtained by cultivation of the fungus at alkaline pH in an iron-restricted liquid culture medium. Siderophores were then extracted from the culture filtrate by liquid/liquid extraction, and separated by reverse phase high performance liquid chromatography. Two siderophores, dimerumic acid and Nα-methyl coprogen B, were identified by electrospray ionization-mass spectrometry and MS-MS fragmentation. Finally, comparison of various strains suggested a higher production of Na-methyl coprogen B by clinical isolates of respiratory origin. Studies are initiated in order to determine the potential usefulness of these siderophores as diagnostic markers of scedosporiosis.


Assuntos
Dicetopiperazinas/química , Ácidos Hidroxâmicos/química , Sideróforos/química , Biomarcadores , Cromatografia Líquida de Alta Pressão , Meios de Cultura , Dicetopiperazinas/isolamento & purificação , Humanos , Concentração de Íons de Hidrogênio , Ácidos Hidroxâmicos/isolamento & purificação , Hidroxibenzoatos/análise , Indicadores e Reagentes/análise , Ferro/metabolismo , Pneumopatias Fúngicas/microbiologia , Scedosporium/crescimento & desenvolvimento , Scedosporium/metabolismo , Sideróforos/isolamento & purificação , Sideróforos/metabolismo , Espectrometria de Massas por Ionização por Electrospray
17.
Bioorg Med Chem Lett ; 15(8): 2007-10, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15808457

RESUMO

Analogues of the antimalarial alkaloid nitidine have been prepared with high potency against both chloroquine-sensitive and -resistant strains of Plasmodium falciparum in vitro. Simple modifications, using an established synthetic route, resulted in an analogue with IC(50) below 5ng/mL against a chloroquine-sensitive strain of P. falciparum. N-Ethylethoxidine had IC(50) below 30ng/mL against both chloroquine-sensitive and chloroquine-resistant strains of P. falciparum.


Assuntos
Antimaláricos/química , Fenantridinas/química , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Netropsina/química , Netropsina/farmacologia , Fenantridinas/farmacologia , Plasmodium falciparum/fisiologia
18.
Life Sci ; 75(25): 3077-85, 2004 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-15474559

RESUMO

The antimalarial activity of 22 xanthones against chloroquino-resistant strains of Plasmodium falciparum was evaluated. Natural caloxanthone C (1), demethylcalabaxanthone (2), calothwaitesixanthone (3), calozeyloxanthone (4), dombakinaxanthone (5), macluraxanthone (6), and 6-deoxy-gamma-mangostin (7) were isolated from Calophyllum caledonicum. 1,6-dihydroxyxanthone (8), pancixanthone A (9), isocudraniaxanthone B (10), isocudraniaxanthone A (11), 2-deprenylrheediaxanthone B (12) and 1,4,5-trihydroxyxanthone (13) were isolated from Garcinia vieillardii. Moreover, synthetic compounds (14-22) are analogues or intermediates of xanthones purified from Calophyllum caledonicum (Oger J.M., Morel C., Helesbeux J.J., Litaudon M., Seraphin D., Dartiguelongue C., Larcher G., Richomme P., Duval O. 2003. First 2-Hydroxy-3-Methylbut-3-Enyl substituted xanthones isolated from Plants: structure elucidation, synthesis and antifungal activity. Natural Product Research 17(3), 195-199; Helesbeux J.J., Duval O., Dartiguelongue C., Seraphin D., Oger J.M., Richomme P., 2004. Synthesis of 2-hydroxy-3-methylbut-3-enyl substituted coumarins and xanthones as natural products. Application of the Schenck ene reaction of singlet oxygen with ortho-prenylphenol precursors. Tetrahedron 60(10), 2293-2300). The relationship between antimalarial activity and molecular structure of xanthones has also been explored. The most potent xanthones (2), (3) and (7) (IC50 = c.a. 1.0 microg/mL) are 1,3,7 trioxygenated and prenylated on the positions 2 and 8.


Assuntos
Antimaláricos/farmacologia , Calophyllum/química , Garcinia/química , Xantonas/farmacologia , Animais , Plasmodium falciparum/efeitos dos fármacos , Relação Estrutura-Atividade
19.
Rapid Commun Mass Spectrom ; 18(4): 474-82, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14966856

RESUMO

Ethoxidine (N-methyl-12-ethoxy-2,3,8,9-tetramethoxybenzo[c]phenanthridinium methylsulfonate salt) is a synthetic 2-methoxy-12-ethoxy derivative of the natural alkaloid fagaronine. This new inhibitor of DNA-topoisomerase I is considered as a potential antitumor agent with higher in vitro activity than fagaronine. In order to further improve the efficiency of ethoxidine, its in vitro biotransformation by hepatic monooxygenases and the structures of its metabolites were investigated by high-performance liquid chromatography (HPLC) combined with electrospray ionization tandem mass spectrometry (ESI-MS/MS) and accurate mass measurement by time-of-flight mass spectrometry (TOFMS). When ethoxidine was incubated with BNF-treated rat liver microsomes or with cells expressing different recombinant human cytochrome P450, the same four ethoxidine metabolites (m(1)-m(4)) were detected and were formed exclusively by CYP1A1. The structures of these metabolites were assigned from ESI-MS/MS mass spectra and compared with those of ethoxidine derivatives. Accurate mass measurements of in-source ESI-TOFMS fragment ions exhibited successive neutral losses of C(2)H(4) and CO for ethoxidine and its metabolites. Whereas a 15 Da loss (methyl radical) was observed for the metabolites m(1)-m(4) containing a quaternary ammonium group, a 16 Da loss (methane) was observed for ethoxidine and could have resulted from the presence of two methoxy groups at adjacent positions (C-2 and C-3). The proposed oxidative modifications of ethoxidine were further confirmed by determination of the number of exchangeable hydrogen atoms and by the proposed elemental compositions of the metabolites based on accurate mass measurements by TOFMS. Two major metabolites resulted from O-demethylation of ethoxidine; one was tentatively identified as 12-ethoxyfagaronine (m(3)) and the second as an O-demethylated ethoxidine isomer (m(4)). Two polar metabolites were shown to be O-demethylated (m(1)) and hydroxylated (m(2)) derivatives of 12-ethoxyfagaronine. When 12-ethoxyfagaronine was incubated under the same conditions as ethoxidine, m(2) was formed, thus supporting the proposal that 12-ethoxyfagaronine is the primary oxidative product of ethoxidine.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Citocromo P-450 CYP1A1/metabolismo , Microssomos Hepáticos/metabolismo , Fenantridinas/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Linhagem Celular , Humanos , Microssomos Hepáticos/enzimologia , Estrutura Molecular , Peso Molecular , Fenantridinas/química , Ratos , Proteínas Recombinantes , Sensibilidade e Especificidade
20.
J Enzyme Inhib Med Chem ; 19(6): 481-7, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15662952

RESUMO

The synthesis of benzo[c]phenanthridine alkaloid derivatives is described. In vitro antiviral activity against herpes simplex type 1 (HSV1) has been investigated. Contrary to the natural product fagaronine, which did not have any activity in the HSV1 antiviral tests, four 12-alkoxy derivatives showed good activity demonstrating the importance of the 12-substitution in the structure-activity relationships.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Fenantridinas/síntese química , Fenantridinas/farmacologia , Animais , Antivirais/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fenantridinas/química , Relação Estrutura-Atividade , Células Vero
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