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1.
J Am Chem Soc ; 143(49): 21037-21047, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34870420

RESUMEN

Euonymine (1) and euonyminol octaacetate (2) share the core structure of euonyminol (3), the most hydroxylated member of the dihydro-ß-agarofuran family. In 2, eight of the nine hydroxy groups of 3 are acetylated, and 1 has six acetyl groups and a 14-membered bislactone comprising a pyridine dicarboxylic acid with two methyl groups. The different acylation patterns provide distinct biological activities: 1 and 2 display anti-HIV and P-glycoprotein inhibitory effects, respectively. The 11 contiguous stereocenters and 9 oxygen functionalities of the ABC-ring system of 1 and 2 represent a formidable challenge, which is further heightened by the macrocyclic structure of 1. Here we disclose an efficient synthetic strategy for enantioselective total synthesis of 1 and 2. Starting from (R)-glycerol acetonide, we constructed the B-ring by an Et3N-accelerated Diels-Alder reaction, the C-ring by intramolecular iodoetherification, and the A-ring by ring-closing olefin metathesis. The 10 stereocenters were installed through a series of substrate-controlled stereoselective C-C and C-O bond formations by exploiting the three-dimensional structures of judiciously designed substrates. These newly developed reaction sequences led to protected euonyminol 5, which served as a common intermediate for assembling 1 and 2. Global deprotection of 5 and subsequent acetylation produced 2. Alternatively, the discriminative protective groups of 5 allowed for site-selective bis-esterification to generate bislactone. Combining [3 + 2]-cycloaddition and reductive desulfurization introduced the last remaining stereocenters of the two methyl groups on the macrocycle. Finally, deprotection and acetylation gave rise to fully synthetic 1 for the first time.


Asunto(s)
Niacina/análogos & derivados , Niacina/síntesis química , Sesquiterpenos/síntesis química , Acetilación , Reacción de Cicloadición , Estereoisomerismo
2.
Bioorg Med Chem ; 27(15): 3307-3318, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31204228

RESUMEN

Based on the structures of nicotinic acid and chlorfibrate, a series of new H2S donors were synthesized and their anti-atherosclerosis activities using Ox-LDL RAW 264.6 cells as model were evaluated. The release test showed that all the compounds could release H2S effectively and showed low cytotoxicity. In the bioactivity experiments, compounds 1, 3, 9 and 14 increased the survival rate of HUVEC cells treated by ox-LDL; among four compounds, compounds 1 and 3 displayed higher activity than the others. In the foam cell model, compounds 1 and 3 were found to inhibit the formation of foam cells and significantly reduced the content of TC and FC in foam cells. They had more obvious effects on lipid reduction than those of nicotinic acid and chlorfibrate. In anti-oxidation, compounds 1 and 3 significantly reduced ROS and MDA and increased the expression level of SOD, whereas the precursor compounds, niacin and chlorfibrate had little antioxidant effect. In addition, both compounds also inhibited the inflammatory response in foam cells, with reducing pro-inflammatory factor TNF-α and increasing anti-inflammatory cytokine IL-10. WB assay showed that the tested compounds inhibited the expression levels PI3K, Akt and NF-κb proteins. In conclusion, the compounds as H2S donors could protect HUVEC cells from damage and inhibit the formation of foam cells by inhibiting PI3K/Akt/NF-κb signal pathway. All these suggest the compounds have potential to be candidate for anti-atherosclerosis medicines.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Antioxidantes/farmacología , Aterosclerosis/tratamiento farmacológico , Clofibrato/farmacología , Sulfuro de Hidrógeno/metabolismo , Niacina/farmacología , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Antioxidantes/síntesis química , Antioxidantes/química , Aterosclerosis/metabolismo , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Clofibrato/síntesis química , Clofibrato/química , Relación Dosis-Respuesta a Droga , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Sulfuro de Hidrógeno/análisis , Ratones , Estructura Molecular , Niacina/síntesis química , Niacina/química , Células RAW 264.7 , Relación Estructura-Actividad
3.
Bioorg Med Chem Lett ; 27(7): 1611-1615, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28238612

RESUMEN

Novel cytotoxins 3-5 containing the 1,5-diaryl-3-oxo-1,4-pentadienyl pharmacophore are disclosed. The compounds in series 3 and 5 have the potential to liberate niacin which may reduce some of the side effects of antineoplastic compounds. 3a-c emerged as the most potent cytotoxic compounds with IC50 values in the low micromolar range against human Molt4/C8 and CEM CD4+ T-lymphocytes as well as murine L1210 leukemia cells. QSAR studies revealed that cytotoxic potencies were negatively correlated with the magnitude of the Hammett sigma values of the aryl substituents. The compounds 3a-e displayed tumour-selective toxicity against human HL-60, HSC-2, HSC-3 and HSC-4 neoplasms as compared to human HGF, HPC and HPLF nonmalignant cells. A representative potent compound 3a caused PARP1 cleavage and G0/G1 cell cycle arrest in HSC-2 cells. These compounds are well tolerated in mice at doses up to and including 300mg/kg of the compounds and no mortalities were noted after 4h. The stability studies undertaken did not reveal that a representative compound 3a underwent hydrolysis to the related phenol 2a. Some guidelines for further analog development of the novel esters 3 were made.


Asunto(s)
Antineoplásicos/farmacología , Compuestos de Bencilideno/farmacología , Ciclohexanonas/farmacología , Niacina/análogos & derivados , Niacina/farmacología , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/síntesis química , Antineoplásicos/toxicidad , Compuestos de Bencilideno/administración & dosificación , Compuestos de Bencilideno/síntesis química , Compuestos de Bencilideno/toxicidad , Línea Celular Tumoral , Ciclohexanonas/administración & dosificación , Ciclohexanonas/síntesis química , Ciclohexanonas/toxicidad , Ensayos de Selección de Medicamentos Antitumorales , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Hidrólisis , Melfalán/farmacología , Ratones , Niacina/administración & dosificación , Niacina/síntesis química , Niacina/toxicidad , Poli(ADP-Ribosa) Polimerasa-1/química , Relación Estructura-Actividad Cuantitativa , Ratas
4.
Bioorg Med Chem Lett ; 26(24): 5896-5898, 2016 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-27866817

RESUMEN

There is an urgent need for novel drugs for the treatment of tuberculosis (TB) due to the increasing prevalence of antibiotic resistance among Mycobacterium tuberculosis (Mtb) strains against first-line and second-line therapeutics. We developed novel N-phenyl 1,4-dihydropyridines as potential antituberculotic agents. The observed activity depends on the substitution patterns of the aromatic residues. N-unsubstituted 1,4-dihydropyridines are known inhibitors of the cancer-relevant transmembrane efflux pump ABCB1. Based on the similarity of ABCB1 amino acids sequences relevant to 1,4-dihydropyridine binding and the MTb efflux pump Rv0194, we determined ABCB1-inhibitory properties of our compounds in a cell line model. We identified one compound, which substantially increased the activity of two antituberculotic drugs which are substrates of ABCB1. The data indicate that our N-phenyl 1,4-dihydropyridines represent a novel compound class which improves the efficacy of anti-TB drugs by interfering with transmembrane efflux pumps in Mtb.


Asunto(s)
Antibacterianos/farmacología , Descubrimiento de Drogas , Mycobacterium tuberculosis/efectos de los fármacos , Niacina/análogos & derivados , Antibacterianos/síntesis química , Antibacterianos/química , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Niacina/síntesis química , Niacina/química , Niacina/farmacología , Relación Estructura-Actividad
5.
Molecules ; 19(4): 4791-801, 2014 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-24743936

RESUMEN

A novel twin drug consisting of nicotinic acid (VB3) and quercetin tetramethyl ether (QTME) has been synthesized as an antihypertensive in a total yield of 79.2% through methylation, hydrolysis, acylation and esterification starting from rutin. The structures of synthesized compounds were elucidated by 1H-NMR, 13C-NMR and elemental analysis. The anti-hypertensive effects of an oral daily dose (15 mg/kg) of the synthesized compounds in spontaneously hypertensive (SHR) rats and normotensive Wistar Kyoto (WKY) rats were analysed. The data demonstrate that the twin drug VB3-QTME both reduces the elevated blood pressure and prolongs the action time in SHR rats without effect on WKY rats. However, definitive evidence of a precise mechanism of action by which VB3-QTME might decrease blood pressure remains elusive. Based on the results, the therapeutic potential of this twin drug is discussed.


Asunto(s)
Antihipertensivos/farmacología , Hipertensión/tratamiento farmacológico , Niacina/farmacología , Quercetina/farmacología , Administración Oral , Animales , Antihipertensivos/síntesis química , Presión Sanguínea/efectos de los fármacos , Éteres , Hipertensión/fisiopatología , Masculino , Niacina/análogos & derivados , Niacina/síntesis química , Quercetina/análogos & derivados , Quercetina/síntesis química , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Rutina/química , Factores de Tiempo
7.
Drug Dev Ind Pharm ; 37(9): 1090-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21401343

RESUMEN

Nicotinic acid is therapeutically the optimum antihyperlipidemic agent, yet its intolerable cutaneous flushing hinders its wide clinical implication. The codrug of nicotinic acid and ibuprofen (IBP) was synthesized in the aim of overcoming the troublesome side effect of nicotinic acid by blockade of prostaglandin synthesis through released IBP, thus enhance patient's compliance. The physico-chemical properties of codrug namely solubility, partition coefficient, and pKa were determined. Its solubility in aqueous and organic solvents was highest in 0.1 M HCl and isopropanol, respectively. The kinetics of hydrolysis of the codrug and IBP 2-hydroxyethyl ester was studied in aqueous phosphate buffer solution in pH 1.2, 6.8, and 7.4 at 70°C, 80°C, and 90°C. The hydrolysis was found to be pH dependent and followed Arrhenius equation. The half-life of codrug and IBP 2-hydroxyethyl ester at 25°C in pH 7.4 was 218 days and 3 years, respectively. In vitro enzymatic hydrolysis of codrug and IBP 2-hydroxyethyl ester was studied in human plasma and rat liver homogenate. Codrug and IBP 2-hydroxyethyl ester exhibited faster in vitro enzymatic hydrolysis than in vitro chemical hydrolysis. The pseudo-first-order rate constants were 0.0113, 0.177 min(-1) for codrug and 0.0006, 0.0569 min(-1) for IBP 2-hydroxyethyl ester in human plasma and rat liver homogenate, respectively. Thus, nicotinic acid will be rapidly released from codrug to manage dyslipidemia, followed by the later release of IBP from IBP 2-hydroxyethyl ester to alleviate nicotinic acid cutaneous flushing.


Asunto(s)
Inhibidores de la Ciclooxigenasa/síntesis química , Hipolipemiantes/síntesis química , Ibuprofeno/síntesis química , Niacina/síntesis química , Animales , Inhibidores de la Ciclooxigenasa/química , Inhibidores de la Ciclooxigenasa/farmacología , Combinación de Medicamentos , Diseño de Fármacos , Dislipidemias/tratamiento farmacológico , Semivida , Humanos , Hidrólisis , Hipolipemiantes/química , Hipolipemiantes/farmacología , Ibuprofeno/química , Ibuprofeno/farmacología , Masculino , Niacina/química , Niacina/farmacología , Ratas , Ratas Wistar
8.
Nat Commun ; 11(1): 6308, 2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-33298909

RESUMEN

Despite the availability of numerous routes to substituted nicotinates based on the Bohlmann-Rahtz pyridine synthesis, the existing methods have several limitations, such as the inevitable ortho-substitutions and the inability to conjugate vitamin B3 to other pharmaceutical agents. Inspired by the biosynthesis of nicotinic acid (a form of vitamin B3) from tryptophan, we herein report the development of a strategy for the synthesis of meta-aminoaryl nicotinates from 3-formyl(aza)indoles. Our strategy is mechanistically different from the reported routes and involves the transformation of (aza)indole scaffolds into substituted meta-aminobiaryl scaffolds via Aldol-type addition and intramolecular cyclization followed by C-N bond cleavage and re-aromatization. Unlike previous synthetic routes, this biomimetic method utilizes propiolates as enamine precursors and thus allows access to ortho-unsubstituted nicotinates. In addition, the synthetic feasibility toward the halo-/boronic ester-substituted aminobiaryls clearly differentiates the present strategy from other cross-coupling strategies. Most importantly, our method enables the late-stage conjugation of bioactive (hetero)arylamines with nicotinates and nicotinamides and allows access to the previously unexplored chemical space for biomedical research.


Asunto(s)
Aminas/síntesis química , Biomimética/métodos , Técnicas de Química Sintética/métodos , Niacina/síntesis química , Niacinamida/síntesis química , Compuestos Aza/síntesis química , Ciclización , Estudios de Factibilidad , Indoles/síntesis química , Estructura Molecular , Niacina/análogos & derivados , Niacinamida/análogos & derivados
9.
Biomacromolecules ; 10(11): 3023-7, 2009 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-19821557

RESUMEN

Thiolated chitosans are relatively new thiolated biopolymers exhibiting mucoadhesive, enzyme inhibitory, and permeation enhancing properties. A drawback, however, is their pH dependent reactivity. The aim of this study was therefore to develop a novel thiolated chitosan showing a non pH dependent reactivity of its thiol groups. For this purpose, 6-mercaptonicotinic acid (6-MNA) was covalently attached to chitosan by a carbodiimide mediated reaction. The obtained conjugate was characterized in vitro by quantification of immobilized thiol groups, cytotoxicity, in situ gelling properties, and disulfide bond formation at different pH. The synthesized conjugate displayed up to 973.80 micromol thiol groups per gram of polymer in reduced form. The polymer was nontoxic and showed in situ gelling properties. Furthermore, disulfide bond formation and therefore gelling properties occurred at various pH ranges. The reactivity of thiol groups was in the same range at pH 3 and pH 6.8. According to these results, chitosan-6 mercaptonicotinic acid seems to have some promising features to be used particularly for mucoadhesive formulations.


Asunto(s)
Materiales Biocompatibles/síntesis química , Quitosano/análogos & derivados , Quitosano/síntesis química , Niacina/síntesis química , Compuestos de Sulfhidrilo/síntesis química , Materiales Biocompatibles/efectos adversos , Materiales Biocompatibles/química , Células CACO-2 , Humanos , Niacina/química , Compuestos de Sulfhidrilo/química , Viscosidad
10.
Med Chem ; 14(8): 851-862, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29669502

RESUMEN

BACKGROUND: The Hantzsch ester, diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5- dicarboxylate, has been used as a hydride donor and its various biological effects have been reported. To identify chemotherapeutic agents with apoptotic effects, 21 diethyl 2,6-dimethyl-1,4- dihydropyridine-3,5-dicarboxylates were designed and synthesized; they have not been reported as apoptosis inducers thus far. Their structure-cytotoxicity relationships were investigated. Further biological experiments were performed on the title compound. METHODS: The cytotoxicities of the current synthetic compounds were measured using a clonogenic assay in HCT116 human colon cancer cells. An annexin V staining assay was used to confirm if the title compound induced apoptosis. To identify the synthetic compounds, Nuclear Magnetic Resonance (NMR) spectroscopy and high-resolution mass spectrometry (HR-MS) were conducted. As molecular symmetry was observed in the NMR spectroscopic data, the three dimensional structures were determined from ab initio calculations and X-ray crystallography. RESULTS: The results obtained from NMR spectroscopy, ab initio calculations, and X-ray crystallography revealed that the diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate derivatives synthesized in this research have symmetric structures. The cytotoxicities of the 21 derivatives were tested in the HCT116 human colon cancer cell lines, and their half-maximal cell growth inhibitory concentrations ranged between 16.29 and 68.88 µM. Structure-cytotoxicity relationships demonstrated that bulky substitutions were preferred, para-positioned substituents tended to have better cytotoxic values, and the polarity may have a function as well. The cytotoxicity of the title compound in HCT116 colon cancer cells was mediated through apoptotic cell death. CONCLUSION: To obtain chemotherapeutic agents that induce apoptosis, 21 diethyl 2,6-dimethyl- 1,4-dihydropyridine-3,5-dicarboxylates were designed and synthesized. NMR spectroscopy, ab initio calculations, and X-ray crystallography demonstrated that the diethyl 2,6-dimethyl-1,4- dihydropyridine-3,5-dicarboxylate derivatives synthesized in this research had symmetric structures. Even if the half-maximal cell growth inhibitory concentrations of the 21 derivatives did not show dramatic inhibitory activity against HCT116 human colon cancer cells, small changes in the structure affected the anticancer activities. Treatment with diethyl 4-(4-chlorophenyl)-2,6- dimethyl-1,4-dihydropyridine-3,5-dicarboxylate substantially reduced the cell viability and the cytotoxicity against HCT116 colon cancer cells was mediated through apoptotic cell death. As the ability of diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylates to induce apoptosis has not been previously reported, we have now reported their design, synthesis, cytotoxicity, and structureactivity relationships.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Dihidropiridinas/farmacología , Ésteres/farmacología , Niacina/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Caspasa 7/metabolismo , Caspasa 9/metabolismo , Supervivencia Celular/efectos de los fármacos , Dihidropiridinas/síntesis química , Dihidropiridinas/química , Ésteres/síntesis química , Ésteres/química , Células HCT116 , Humanos , Modelos Químicos , Niacina/análogos & derivados , Niacina/síntesis química , Teoría Cuántica , Relación Estructura-Actividad
11.
Eur J Med Chem ; 146: 185-193, 2018 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-29407949

RESUMEN

A series of novel 4,6-diphenyl-2-(1H-pyrrol-1-yl)nicotinonitrile analogues of crolibulin and combretastatin A-4 (CA-4) were discovered using a 2-(1H-pyrrol-1-yl)pyridine ring as link-bridge to retain the cis-orientations of A-ring and B-ring. All the target compounds were synthesized and evaluated for their antiproliferative activity against five human cancer cell lines. Compounds 6a-d exhibited superior potency, with IC50 values at nanomolar levels. In particular, compound 6a exhibited antitumor activity similar to or higher than crolibulin and CA-4. Moreover, the inhibition of microtubule assembly by compound 6a was comparable to that by CA-4. A molecular modeling study of compound 6a was performed to elucidate its binding mode at the colchicine binding site in the tubulin dimer, which also provided a basis for further structure-guided design of novel colchicine binding site inhibitors.


Asunto(s)
Antineoplásicos/farmacología , Benzopiranos/farmacología , Niacina/farmacología , Nitrilos/farmacología , Estilbenos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Benzopiranos/química , Sitios de Unión/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Colchicina/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Microtúbulos/efectos de los fármacos , Modelos Moleculares , Estructura Molecular , Niacina/análogos & derivados , Niacina/síntesis química , Niacina/química , Nitrilos/síntesis química , Nitrilos/química , Estilbenos/química , Relación Estructura-Actividad
12.
ChemMedChem ; 11(8): 827-33, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-26844930

RESUMEN

The disruption of aberrant protein-protein interactions (PPIs) with synthetic agents remains a challenging goal in contemporary medicinal chemistry but some progress has been made. One such dysregulated PPI is that between the anti-apoptotic Bcl-2 proteins, including myeloid cell leukemia-1 (Mcl-1), and the α-helical Bcl-2 homology-3 (BH3) domains of its pro-apoptotic counterparts, such as Bak. Herein, we describe the discovery of small-molecule inhibitors of the Mcl-1 oncoprotein based on a novel chemotype. Particularly, re-engineering of our α-helix mimetic JY-1-106 into 2,6-di-substituted nicotinates afforded inhibitors of comparable potencies but with significantly decreased molecular weights. The most potent inhibitor 2-(benzyloxy)-6-(4-chloro-3,5-dimethylphenoxy)nicotinic acid (1 r: Ki =2.90 µm) likely binds in the p2 pocket of Mcl-1 and engages R263 in a salt bridge through its carboxylic acid, as supported by 2D (1) H-(15) N HSQC NMR data. Significantly, inhibitors were easily accessed in just four steps, which will facilitate future optimization efforts.


Asunto(s)
Proteína Proapoptótica que Interacciona Mediante Dominios BH3/metabolismo , Benzamidas/farmacología , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Niacina/farmacología , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Proteína Destructora del Antagonista Homólogo bcl-2/metabolismo , para-Aminobenzoatos/farmacología , Proteína Proapoptótica que Interacciona Mediante Dominios BH3/química , Benzamidas/química , Relación Dosis-Respuesta a Droga , Humanos , Modelos Moleculares , Estructura Molecular , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/química , Niacina/síntesis química , Niacina/química , Resonancia Magnética Nuclear Biomolecular , Unión Proteica/efectos de los fármacos , Ingeniería de Proteínas , Bibliotecas de Moléculas Pequeñas/síntesis química , Relación Estructura-Actividad , Proteína Destructora del Antagonista Homólogo bcl-2/química , para-Aminobenzoatos/química
13.
Molecules ; 10(9): 1218-28, 2005 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-18007388

RESUMEN

The coupling reaction of benzoic acid and nicotinic acid hydrazides with N- protected L-amino acids including valine, leucine, phenylalanine, glutamic acid and tyrosine is reported. The target compounds, N-Boc-amino acid-(N;-benzoyl)- and N- Boc-amino acid-(N;-nicotinoyl) hydrazides 5a-5e and 6a-6e were prepared in very high yields and purity using N-[(dimethylamino)-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl- methylene]-N-methyl-methanaminium hexafluorophosphate N-oxide (HATU) as coupling reagent. The antimicrobial activity of the Cu and Cd complexes of the designed compounds was tested. The products were deprotected affording the corresponding amino acid-(N;-benzoyl) hydrazide hydrochloride salts (7a-7e) and amino acid-(N;- nicotinoyl) hydrazide hydrochloride salts (8a-8e). These compounds and their Cu and Cd complexes were also tested for their antimicrobial activity. Several compounds showed comparable activity to that of ampicillin against S. aureus and E. coli.


Asunto(s)
Aminoácidos/síntesis química , Aminoácidos/farmacología , Hidrazinas/síntesis química , Hidrazinas/farmacología , Niacina/análogos & derivados , Niacina/síntesis química , Niacina/farmacología , Aminoácidos/química , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Hidrazinas/química , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Niacina/química , Protones
14.
Eur Rev Med Pharmacol Sci ; 19(20): 3977-88, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26531288

RESUMEN

OBJECTIVE: Niacin, activating G-protein coupled receptor (GPR) 109A, stimulates release of vasodilatory prostaglandins (PGs) such as PGE2 which can elicit niacin-associated flushing side effects. Poly-lactic-co-glycolic acid (PLGA) and poly-lactic acid (PLA) are used in nanoparticle (NP) drug delivery to reduce adverse effects and modulate drug release. Our study evaluated the in vitro effects of niacin-loaded PLGA or PLA-NPs on PGE2 expression in whole human blood as a model for niacin-induced flushing. MATERIALS AND METHODS: NPs were formulated using a solvent evaporation process and characterized by size, polydispersity, zeta potential, drug entrapment, morphology, and drug release. NP in vitro effects on PGE2 release were measured via ELISA analysis. RESULTS: PLGA-NPs demonstrated the lowest NP size (66.7 ± 0.21 nm) with the highest zeta potential and percent drug entrapment (42.00 ± 1.62 mV and 69.09 ± 0.29%, respectively) when compared to PLA-NPs (130.4 ± 0.66 nm, 27.96 ± 0.18 mV, 69.63 ± 0.03 %, respectively). In vitro release studies showed that PLGA-NPs underwent significant reductions in cumulative drug release when compared to PLA-NPs (p < 0.05). Furthermore, when compared to plain niacin, PLGA-NPs significantly reduced in vitro PGE2 release (p < 0.05). CONCLUSIONS: These results support the use of PLGA-NPs as a novel method of delivery for reducing niacin-associated flushing.


Asunto(s)
Química Farmacéutica/métodos , Rubor , Nanopartículas/química , Niacina/síntesis química , Prostaglandinas/sangre , Vasodilatación , Sistemas de Liberación de Medicamentos/métodos , Rubor/inducido químicamente , Rubor/tratamiento farmacológico , Humanos , Ácido Láctico/administración & dosificación , Ácido Láctico/síntesis química , Ácido Láctico/metabolismo , Nanopartículas/administración & dosificación , Nanopartículas/metabolismo , Niacina/administración & dosificación , Niacina/metabolismo , Tamaño de la Partícula , Ácido Poliglicólico/administración & dosificación , Ácido Poliglicólico/síntesis química , Ácido Poliglicólico/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Prostaglandinas/metabolismo , Vasodilatación/efectos de los fármacos , Vasodilatación/fisiología
15.
Chem Commun (Camb) ; 50(49): 6475-8, 2014 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-24817001

RESUMEN

A rationally designed small-molecule fluorogenic probe for nitric oxide (NO) detection based on a new switching mechanism has been developed. Attaching a NO-responsive dihydropyridine pendant group to a fluorophore led to a probe that displays a very high sensitivity to NO concentrations down to the low nM range and a very high specificity to NO while being insensitive to other oxidative oxygen/nitrogen species that often interfere with the sensing of NO.


Asunto(s)
Cumarinas/química , Colorantes Fluorescentes/química , Microscopía Fluorescente , Niacina/análogos & derivados , Óxido Nítrico/análisis , Espectrometría de Fluorescencia , Animales , Línea Celular Tumoral , Cumarinas/síntesis química , Dihidropiridinas/química , Transporte de Electrón , Colorantes Fluorescentes/síntesis química , Concentración de Iones de Hidrógeno , Ratones , Niacina/síntesis química , Niacina/química , Especies de Nitrógeno Reactivo/química , Especies Reactivas de Oxígeno/química
16.
Eur J Med Chem ; 84: 404-16, 2014 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-25038482

RESUMEN

A series of 6-aminonicotinic acid analogues have been synthesized and pharmacologically characterized at native and selected recombinant GABA(A) receptors. 6-Aminonicotinic acid (3) as well as 2- and 4-alkylated analogues (9-11, 14-16) display low to mid-micromolar GABA(A)R binding affinities to native GABA(A) receptors (K(i) 1.1-24 µM). The tetrahydropyridine analogue of 3 (22) shows low-nanomolar affinity (K(i) 0.044 µM) and equipotency as an agonist to GABA itself as well as the standard GABA(A) agonist isoguvacine. Cavities surrounding the core of the GABA binding pocket were predicted by molecular interaction field calculations and docking studies in a α1ß2γ2 GABA(A) receptor homology model, and were confirmed by affinities of substituted analogues of 3. The tight steric requirements observed for the remarkably few GABA(A)R agonists reported to date is challenged by our findings. New openings for agonist design are proposed which potentially could facilitate the exploration of different pharmacological profiles within the GABA(A)R area.


Asunto(s)
Agonistas de Receptores de GABA-A/síntesis química , Agonistas de Receptores de GABA-A/farmacología , Niacina/análogos & derivados , Receptores de GABA-A/metabolismo , Relación Dosis-Respuesta a Droga , Agonistas de Receptores de GABA-A/química , Humanos , Ligandos , Modelos Moleculares , Estructura Molecular , Niacina/síntesis química , Niacina/química , Niacina/farmacología , Relación Estructura-Actividad
17.
Neurol Res ; 35(8): 804-12, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23651620

RESUMEN

OBJECTIVES: The aim of this study was to investigate the effects of oral administration of a novel benzodiazepine derivative, JM-20, on the neurological behavior of different rodent models, focusing on the GABAergic effect. We have also investigated the acute toxicity of oral administration of JM-20 in mice. METHODS: Mice or rats received oral administration of JM-20 at 2, 4, 8, and 10 mg/kg to evaluate the sedative/hypnotic, anxiolytic, and anticonvulsant effects, as well as the influence on the stereotyped behavior induced by amphetamine. Diazepam (DZP) was used as a positive control. In addition, the mice received a single oral JM-20 dose of 2000 mg/kg to evaluate the acute toxicity. RESULTS: In a dose-dependent manner, JM-20 (i) increased the number of crossings and decreased the number of rearings in the open-field test; (ii) decreased the aggressive behavior of socially-isolated mice; and (iii) increased the latency period for tonic seizure's onset and the percentage of survival of animals with seizures. Moreover, JM-20 increased the sleeping time induced by barbiturates and the time spent and the number of entries in the open arms of the elevated plus-maze test. In the JM-20 toxicity test, no mortality was observed and only minor signs of toxicity associated with sedation were detected. CONCLUSIONS: These results indicate that JM-20 has an anxiolytic profile similar to DZP and its dihydropyridine moiety did not appear to interfere with the GABAergic activity associated with benzodiazepine. Furthermore, JM-20 did not show significant acute toxic effects in mice.


Asunto(s)
Ansiolíticos/farmacología , Conducta Animal/efectos de los fármacos , Benzodiazepinas/química , Dihidropiridinas/química , Hipnóticos y Sedantes/farmacología , Niacina/análogos & derivados , Administración Oral , Animales , Ansiolíticos/administración & dosificación , Ansiolíticos/efectos adversos , Ansiolíticos/toxicidad , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/efectos adversos , Anticonvulsivantes/farmacología , Anticonvulsivantes/toxicidad , Benzodiazepinas/síntesis química , Benzodiazepinas/farmacología , Benzodiazepinas/toxicidad , Diazepam/farmacología , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Interacciones Farmacológicas , Femenino , Hipnóticos y Sedantes/administración & dosificación , Hipnóticos y Sedantes/efectos adversos , Hipnóticos y Sedantes/toxicidad , Masculino , Ratones , Niacina/síntesis química , Niacina/química , Niacina/farmacología , Niacina/toxicidad , Ratas
18.
Artículo en Inglés | MEDLINE | ID: mdl-21459036

RESUMEN

3-(1H-Benzo[d][1,2,3]triazol-1-yl)-1-oxo-1-m-tolylpropan-2-yl-nicotinate (BOTN) has been synthesized and characterized by elemental analysis, IR, UV-vis and fluorescence spectroscopy. Its crystal structure has also been determined by X-ray single crystal diffraction. For BOTN, density functional theory (DFT) calculations of the structure and vibrational frequencies have been performed at B3LYP/6-311G** level. The comparisons between the experimental vibrational frequencies and the predicted data show that B3LYP/6-311G** method can simulate the IR of BOTN on the whole. Based on the vibration analysis, thermodynamic properties of BOTN have been calculated. The correlative equations between the thermodynamic properties and the temperatures have also been listed. The experimental UV-vis spectra present two peaks and theoretical UV-vis spectra obtained by TD-DFT method exhibit three peaks. The comparison between them suggests that the B3LYP/6-311G** method can only approximately simulate the UV-vis spectra of BOTN. The fluorescence determination reveals two emission bands at 423 and 489 nm, respectively.


Asunto(s)
Modelos Moleculares , Niacina/análogos & derivados , Niacina/química , Niacina/síntesis química , Teoría Cuántica , Triazoles/química , Triazoles/síntesis química , Cristalografía por Rayos X , Electrones , Enlace de Hidrógeno , Conformación Molecular , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Termodinámica , Vibración
19.
Eur J Pharm Sci ; 43(3): 99-108, 2011 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-21466853

RESUMEN

Combination therapy of fibrates and nicotinic acid has been reported to be synergistic. Herein, we describe a covalent codrug of gemfibrozil (GEM) and nicotinic acid (NA) that was synthesized and characterized by (1)H NMR, (13)C NMR, FT-IR, MS analysis and elemental analysis. A validated HPLC method was developed that allows for the accurate quantitative determination of the codrug and its hydrolytic products that are formed during the in vitro chemical and enzymatic hydrolysis. The physico-chemical properties of codrug were improved compared to its parent drugs in term of water solubility and partition coefficient. The kinetics of hydrolysis of the codrug was studied using accelerated hydrolysis experiments at high temperatures in aqueous phosphate buffer solution in pH 1.2, 6.8 and 7.4. Using the Arrhenius equation, the extrapolated half-life at 37°C were 289 days at pH 1.2 for the codrug and 130 and 20,315 days at pH 6.8 for the codrug and gemfibrozil 2-hydroxyethyl ester (GHEE), respectively. The shortest half-lives were at pH 7.4; 42 days for the codrug and 5837 days for GHEE, respectively. The hydrolysis of the latter was studied, alone, at 80°C and pH 1.2 and compared to its hydrolysis when it is produced from the codrug using similar conditions. The k(obs) was found in both cases to be 1.60×10(-3)h(-1). The half-lives in plasma were 35.24 min and 26.75 h for the codrug and GHEE, respectively. With regard to liver homogenate, the hydrolysis half-lives were 1.96 min and 48.13 min for the codrug and GHEE, respectively. It can be expected that in vivo, the codrug will liberate NA immediately in plasma then GEM will be liberated from its 2-hydroxyethyl ester in the liver.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Ésteres/síntesis química , Gemfibrozilo/análogos & derivados , Niacina , Ácidos Nicotínicos/síntesis química , Ácidos Nicotínicos/farmacocinética , Profármacos/síntesis química , Ésteres/sangre , Ésteres/metabolismo , Gemfibrozilo/sangre , Gemfibrozilo/síntesis química , Gemfibrozilo/metabolismo , Gemfibrozilo/farmacocinética , Semivida , Humanos , Concentración de Iones de Hidrógeno , Hidrólisis , Hiperlipidemias/patología , Cinética , Hígado/enzimología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Niacina/sangre , Niacina/síntesis química , Niacina/metabolismo , Plasma/enzimología , Profármacos/análisis , Profármacos/metabolismo , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
20.
Eur J Med Chem ; 46(5): 1803-12, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21397370

RESUMEN

We report herein an efficient enantioselective synthesis of SPF32629A and SPF32629B through one-pot enantioselective reduction and protecting-group-free regioselective O-acylation strategy. The absolute configuration of the enantiomerically pure isomers was established by Mosher ester analysis. The inhibitory potencies of the synthesized compounds were assayed in vitro against a panel of microorganisms and against A549 human lung adenocarcinoma cell line. Compounds 2, 11 and 12 displayed moderate to potent antibacterial activity against all the tested strains and compounds 7, 8, 2, 11 and 12 exhibited significant cytotoxicity in a dose-dependent manner with an IC50 values ranging from 2.92 to 4.14 µg/ml and 8-11 µM.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , Bacterias/efectos de los fármacos , Niacina/análogos & derivados , Piridonas/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Niacina/síntesis química , Niacina/química , Niacina/farmacología , Piridonas/síntesis química , Piridonas/química , Estereoisomerismo , Relación Estructura-Actividad , Células Tumorales Cultivadas
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