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1.
Bioorg Med Chem Lett ; 110: 129887, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39002936

RESUMEN

Human cathepsin K (CatK) stands out as a promising target for the treatment of osteoporosis, considering its role in degrading the bone matrix. Given the small and shallow S2 subsite of CatK and considering its preference for proline or hydroxyproline, we now propose the rigidification of the leucine fragment found at the P2 position in a dipeptidyl-based inhibitor, generating rigid proline-based analogs. Accordingly, with these new proline-based peptidomimetics inhibitors, we selectively inhibited CatK against other human cathepsins (B, L and S). Among these new ligands, the most active one exhibited a high affinity (pKi = 7.3 - 50.1 nM) for CatK and no inhibition over the other cathepsins. This specific inhibitor harbors two novel substituents never employed in other CatK inhibitors: the trifluoromethylpyrazole and the 4-methylproline at P3 and P2 positions. These results broaden and advance the path toward new potent and selective inhibitors for CatK.


Asunto(s)
Catepsina K , Peptidomiméticos , Prolina , Catepsina K/antagonistas & inhibidores , Catepsina K/metabolismo , Peptidomiméticos/farmacología , Peptidomiméticos/química , Peptidomiméticos/síntesis química , Prolina/química , Prolina/farmacología , Humanos , Relación Estructura-Actividad , Estructura Molecular , Relación Dosis-Respuesta a Droga
2.
Polymers (Basel) ; 16(8)2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38675080

RESUMEN

Nitrile gloves have become a significant environmental pollutant after the COVID-19 pandemic due to their single-use design. This study examines the capability of P. aeruginosa to use nitrile gloves as its sole carbon energy source. Biodegradation was determined by P. aeruginosa adapting to increasing nitrile glove concentrations at 1%, 3%, and 5% (w/v). The growth kinetics of P. aeruginosa were evaluated, as well as the polymer weight loss. Topographic changes on the glove surfaces were examined using SEM, and FT-IR was used to evaluate the biodegradation products of the nitrile gloves. Following the establishment of a biofilm on the glove surface, the nitrile toxicity was minimized via biodegradation. The result of the average weight loss of nitrile gloves was 2.25%. FT-IR analysis revealed the presence of aldehydes and aliphatic amines associated with biodegradation. SEM showed P. aeruginosa immersed in the EPS matrix, causing the formation of cracks, scales, protrusions, and the presence of semi-spherical particles. We conclude that P. aeruginosa has the capability to use nitrile gloves as its sole carbon source, even up to 5%, through biofilm formation, demonstrating the potential of P. aeruginosa for the degradation of nitrile gloves.

3.
Chemphyschem ; 24(11): e202200867, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36958939

RESUMEN

In this study, we revealed the significance of chemical bonding for the photochemically induced mechanism of 2-phenyl tetrazole derivatives generating nitrile imines. The correlated electron localization function shows that the formation of imine nitrile involves two key bond events: (i) the heterolytic C-N breakage taking place in the T1 state and (ii) the homolytic N-N rupture occurring in the T2 excited state. In particular, a cation-radical specie results from the C-N cleavage, whereas the N-N rupture creates a biradical resonant form of imine nitrile. Additionally, we noticed that the substantial pair delocalization of the C-C-N bonded structure could play a significant role in the conversion of the biradical imine nitrile into both the propargylic and allenic forms via the T1 →S0 deactivation.

4.
Int Dent J ; 73(4): 489-495, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36404177

RESUMEN

AIM: It has been reported that resin composites may experience alterations in their mechanical properties when they come into contact with glove powder. Therefore, the present study aimed to compare the surface microhardness of 3 bulk-fill resin composites handled with latex and nitrile gloves prior to light curing. METHODS: This in vitro experimental study consisted of 90 resin composite specimens with a 6-mm diameter and a 4-mm height divided equally and randomly into 9 groups. Prior to light curing, the resin composites were handled with latex gloves, nitrile gloves, or only a spatula (control). Subsequently, the surface microhardness was measured with an Electronic Vickers Hardness Tester. The Kruskal-Wallis nonparametric H test with Bonferroni correction was used for comparisons. A significance level of 5% (P < .05) was considered. RESULTS: When comparing surface microhardness of each resin composite according to type of handling received, significant differences were observed in Filtek One Bulk Fill (P < .001) and Opus Bulk Fill (P < .001). In addition, these resin composites presented significantly higher surface microhardness than Tetric N-Ceram Bulk Fill resin (P < .05) when handled with latex gloves, nitrile gloves, and only a spatula. Finally, Filtek Bulk Fill resin presented significantly higher surface microhardness compared to Opus Bulk Fill resin when handled with nitrile gloves (P = .038) and a spatula only (P = .033). CONCLUSIONS: The surface microhardness of Filtek One Bulk Fill and Opus Bulk Fill resin composites decreased significantly when handled with latex or nitrile gloves, showing no variation in Tetric N-Ceram Bulk Fill resin composite. In addition, Filtek One Bulk Fill resin composite showed significantly higher surface microhardness than Opus Bulk Fill and Tetric N-Ceram Bulk Fill resin composites when handled with nitrile gloves. It is recommended that bulk-fill resin composites be handled with a spatula, because the use of latex or nitrile gloves could adversely affect their clinical performance.


Asunto(s)
Resinas Compuestas , Látex , Humanos , Ensayo de Materiales , Polimerizacion , Dureza , Propiedades de Superficie
5.
Plant J ; 109(4): 873-890, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34807478

RESUMEN

Trichoderma atroviride is a root-colonizing fungus that confers multiple benefits to plants. In plants, small RNA (sRNA)-mediated gene silencing (sRNA-MGS) plays pivotal roles in growth, development, and pathogen attack. Here, we explored the role of core components of Arabidopsis thaliana sRNA-MGS pathways during its interaction with Trichoderma. Upon interaction with Trichoderma, sRNA-MGS-related genes paralleled the expression of Arabidopsis defense-related genes, linked to salicylic acid (SA) and jasmonic acid (JA) pathways. SA- and JA-related genes were primed by Trichoderma in leaves after the application of the well-known pathogen-associated molecular patterns flg22 and chitin, respectively. Defense-related genes were primed in roots as well, but to different extents and behaviors. Phenotypical characterization of mutants in AGO genes and components of the RNA-dependent DNA methylation (RdDM) pathway revealed that different sets of sRNA-MGS-related genes are essential for (i) the induction of systemic acquired resistance against Botrytis cinerea, (ii) the activation of the expression of plant defense-related genes, and (iii) root colonization by Trichoderma. Additionally, plant growth induced by Trichoderma depends on functional RdDM. Profiling of DNA methylation and histone N-tail modification patterns at the Arabidopsis Nitrile-Specifier Protein-4 (NSP4) locus, which is responsive to Trichoderma, showed altered epigenetic modifications in RdDM mutants. Furthermore, NSP4 is required for the induction of systemic acquired resistance against Botrytis and avoidance of enhanced root colonization by Trichoderma. Together, our results indicate that RdDM is essential in Arabidopsis to establish a beneficial relationship with Trichoderma. We propose that DNA methylation and histone modifications are required for plant priming by the beneficial fungus against B. cinerea.


Asunto(s)
Arabidopsis/genética , Arabidopsis/metabolismo , Resistencia a la Enfermedad/genética , Silenciador del Gen , Hypocreales/genética , Nitrilos/metabolismo , ARN/metabolismo , Proteínas de Arabidopsis/metabolismo , Botrytis , Ciclopentanos , Regulación de la Expresión Génica de las Plantas , Hypocreales/metabolismo , Oxilipinas , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Raíces de Plantas/metabolismo , Ácido Salicílico/metabolismo , Trichoderma/genética , Trichoderma/metabolismo
6.
J Agric Food Chem ; 69(29): 8081-8089, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34279926

RESUMEN

Bryophyllum pinnatum (Lam) Pers. (Crassulaceae) is widely used in folk medicine as leaf juice, aqueous, or hydro-ethanolic extracts. It is also listed as a medicinal plant in several countries such as France and Brazil. The main reported constituents are flavone glycosides, especially those with the rare 3-O-α-l-arabinopyranosyl-(1 → 2)-α-l-rhamnopyranoside moiety. Despite several phytochemical screenings indicating the presence of cyanide derivatives or alkaloids, there are no reports of nitrogenous metabolite characterization from this plant species. Nevertheless, the occurrence and the type of such compounds are of particular interest, as they may account for some of the numerous biological activities and ethnomedicinal uses described for B. pinnatum and could be regarded as chemical/taxonomic markers. Consequently, a hydro-ethanolic extract of B. pinnatum was investigated by using UHPLC-HRMS/MS and the nitrile glucoside sarmentosin was detected for the first time within the genus Bryophyllum/Kalanchoe. Considering the wide use of B. pinnatum and its closely related species for health purposes, the target metabolite was isolated by a combination of centrifugal partition chromatography in elution/extrusion mode and MPLC in order to confirm its structure. A linear, selective, precise, fast, and reliable 1H NMR quantitation method was then developed and validated and may become a tool for easy quality assessment of the plant species. The amount of sarmentosin was determined as 2.07% of the examined sample. Sarmentosin was also detected in Kalanchoe laciniata, confirming the occurrence of this compound within the genus.


Asunto(s)
Kalanchoe , Brasil , Francia , Glicósidos , Nitrilos , Extractos Vegetales , Hojas de la Planta , Espectroscopía de Protones por Resonancia Magnética
7.
Bioorg Med Chem ; 41: 116211, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33991733

RESUMEN

Peptidomimetics of the class of dipeptidyl nitrile analog peptoids were synthesized as inhibitors of mammalian cysteine proteases of the papain superfamily. The dipeptidyl nitrile side chains were attached to the peptide backbone's nitrogen atom, not to the α-carbons. Synthesized nitrile-based peptoid analogs that lack the hydrogen amide at P2-P3 are responsible for many of the secondary structure elements in peptides and proteins, making them resistant to proteolysis. The designed peptoids would lose a hydrogen bond with cruzain Asp161 decreasing the affinity toward the enzyme. A structure-activity relationship and matched molecular pair-based analysis between the dipeptidyl nitrile Neq0409 and its peptoid 4a yielded the following cruzain affinities: pKiNeq0409 = 6.5 and pKi4a = 5.2. respectively. A retrosynthetic matched molecular pair cliff (RMMP-cliff) analysis with a ΔpKiNeq0409-4a of 1.3 log is found for this transformation. These novel peptoids were then optimized, leading to compound 4i, with high cruzain inhibition (pKi = 6.8). Cross-class cathepsin activity was observed for some of these novel compounds against cathepsins K, L and S, while other compounds presented a selective inhibition of cathepsin K (4b, 4c, 4k) over ten times higher than the other enzymes. The putative mode of binding was determined by using covalent docking, which also aided to describe the structure-activity relationship (SAR). Interestingly, none of the peptoids inhibited CatB to any appreciable extent. These results provide guidance to identify novel bioactive nitrile-based peptoids.


Asunto(s)
Inhibidores de Cisteína Proteinasa/farmacología , Nitrilos/química , Péptidos/farmacología , Inhibidores de Cisteína Proteinasa/química , Modelos Moleculares , Simulación del Acoplamiento Molecular , Estructura Molecular , Péptidos/química
8.
Bioorg Med Chem ; 29: 115827, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33254069

RESUMEN

Human cathepsin B (CatB) is an important biological target in cancer therapy. In this work, we performed a knowledge-based design approach and the synthesis of a new set of 19 peptide-like nitrile-based cathepsin inhibitors. Reported compounds were assayed against a panel of human cysteine proteases: CatB, CatL, CatK, and CatS. Three compounds (7h, 7i, and 7j) displayed nanomolar inhibition of CatB and selectivity over CatK and CatL. The selectivity was achieved by using the combination of a para biphenyl ring at P3, halogenated phenylalanine in P2 and Thr-O-Bz group at P1. Likewise, compounds 7i and 7j showed selective CatB inhibition among the panel of enzymes studied. We have also described a successful example of bioisosteric replacement of the amide bond for a sulfonamide one [7e â†’ 6b], where we observed an increase in affinity and selectivity for CatB while lowering the compound lipophilicity (ilogP). Our knowledge-based design approach and the respective structure-activity relationships provide insights into the specific ligand-target interactions for therapeutically relevant cathepsins.


Asunto(s)
Amidas/farmacología , Aminas/farmacología , Catepsina B/antagonistas & inhibidores , Catepsina L/antagonistas & inhibidores , Diseño de Fármacos , Inhibidores Enzimáticos/farmacología , Amidas/síntesis química , Amidas/química , Aminas/síntesis química , Aminas/química , Catepsina B/metabolismo , Catepsina L/metabolismo , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Simulación de Dinámica Molecular , Estructura Molecular , Relación Estructura-Actividad
9.
Bioorg Med Chem ; 28(22): 115743, 2020 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-33038787

RESUMEN

Leishmania mexicana is an obligate intracellular protozoan parasite that causes the cutaneous form of leishmaniasis affecting South America and Mexico. The cysteine protease LmCPB is essential for the virulence of the parasite and therefore, it is an appealing target for antiparasitic therapy. A library of nitrile-based cysteine protease inhibitors was screened against LmCPB to develop a treatment of cutaneous leishmaniasis. Several compounds are sufficiently high-affinity LmCPB inhibitors to serve both as starting points for drug discovery projects and as probes for target validation. A 1.4 Å X ray crystal structure, the first to be reported for LmCPB, was determined for the complex of this enzyme covalently bound to an azadipeptide nitrile ligand. Mapping the structure-activity relationships for LmCPB inhibition revealed superadditive effects for two pairs of structural transformations. Therefore, this work advances our understanding of azadipeptidyl and dipeptidyl nitrile structure-activity relationships for LmCPB structure-based inhibitor design. We also tested the same series of inhibitors on related cysteine proteases cathepsin L and Trypanosoma cruzi cruzain. The modulation of these mammalian and protozoan proteases represents a new framework for targeting papain-like cysteine proteases.


Asunto(s)
Compuestos Aza/farmacología , Catepsina B/antagonistas & inhibidores , Inhibidores de Cisteína Proteinasa/farmacología , Leishmania mexicana/efectos de los fármacos , Tripanocidas/farmacología , Compuestos Aza/síntesis química , Compuestos Aza/química , Catepsina B/metabolismo , Cristalografía por Rayos X , Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa/síntesis química , Inhibidores de Cisteína Proteinasa/química , Dipéptidos/síntesis química , Dipéptidos/química , Dipéptidos/farmacología , Relación Dosis-Respuesta a Droga , Leishmania mexicana/enzimología , Simulación de Dinámica Molecular , Estructura Molecular , Nitrilos/síntesis química , Nitrilos/química , Nitrilos/farmacología , Proteínas Protozoarias/antagonistas & inhibidores , Proteínas Protozoarias/metabolismo , Relación Estructura-Actividad , Tripanocidas/síntesis química , Tripanocidas/química
10.
Bioorg Med Chem Lett ; 30(18): 127439, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32717373

RESUMEN

Cysteine protease B (CPB) can be targeted by reversible covalent inhibitors that could serve as antileishmanial compounds. Here, sixteen dipeptidyl nitrile derivatives were synthesized, tested against CPB, and analyzed using matched molecular pairs to determine the effects of stereochemistry and p-phenyl substitution on enzyme inhibition. The compound (S)-2-(((S)-1-(4-bromophenyl)-2,2,2-trifluoroethyl)amino)-N-(1-cyanocyclopropyl)-3-phenylpropanamide (5) was the most potent CPB inhibitor (pKi = 6.82), which was also selective for human cathepsin B (pKi < 5). The inversion of the stereochemistry from S to R was more detrimental to potency when placed at the P2 position than at P3. The p-Br derivatives were more potent than the p-CH3 and p-OCH3 derivatives, probably due to intermolecular interactions with the S3 subsite.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa/síntesis química , Inhibidores de Cisteína Proteinasa/metabolismo , Cisteína/química , Nitrilos/síntesis química , Sitios de Unión , Catepsina B/metabolismo , Evaluación Preclínica de Medicamentos , Humanos , Modelos Moleculares , Unión Proteica , Estereoisomerismo , Relación Estructura-Actividad
11.
Molecules ; 25(4)2020 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-32054008

RESUMEN

Glucosinolates are secondary plant metabolites of Brassicaceae. They exert their effect after enzymatic hydrolysis to yield aglycones, which become nitriles and epithionitriles through the action of epithiospecifier (ESP) and nitrile-specifier proteins (NSP). The mechanism of action of broccoli ESP and NSP is poorly understood mainly because ESP and NSP structures have not been completely characterized and because aglycones are unstable, thus hindering experimental measurements. The aim of this work was to investigate the interaction of broccoli ESP and NSP with the aglycones derived from broccoli glucosinolates using molecular simulations. The three-dimensional structure of broccoli ESP was built based on its amino-acid sequence, and the NSP structure was constructed based on a consensus amino-acid sequence. The models obtained using Iterative Threading ASSEmbly Refinement (I-TASSER) were refined with the OPLS-AA/L all atom force field of GROMACS 5.0.7 and were validated by Veryfy3D and ERRAT. The structures were selected based on molecular dynamics simulations. Interactions between the proteins and aglycones were simulated with Autodock Vina at different pH. It was concluded that pH determines the stability of the complexes and that the aglycone derived from glucoraphanin has the highest affinity to both ESP and NSP. This agrees with the fact that glucoraphanin is the most abundant glucosinolate in broccoli florets.


Asunto(s)
Brassica/química , Enzimas/química , Modelos Moleculares , Nitrilos/química , Proteínas de Plantas/química , Secuencia de Aminoácidos , Isotiocianatos/química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Conformación Proteica
12.
Anticancer Agents Med Chem ; 19(1): 112-120, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30370859

RESUMEN

BACKGROUND: Pancreatic cancer is one of the most aggressive types with high mortality in patients. Therefore, studies to discover new drugs based on cellular targets have been developed to treat this disease. Due to the importance of Cysteine Protease (CP) to several cellular processes in cancer cells, CP inhibitors have been studied as novel alternative approaches for pancreatic cancer therapy. OBJECTIVE: The cytostatic potential of new CP inhibitors derived from dipeptidyl nitriles is analyzed in vitro using pancreatic cancer (MIA PaCa-2) cells. METHODS: The cytotoxic and cytostatic activities were studied using MTT colorimetric assay in 2D and 3D cultures. Colony formation, migration in Boyden chamber and cell cycle analysis were applied to further study the cytostatic activity. The inhibition of cysteine proteases was evaluated with Z-FR-MCA selective substrate, and ROS evaluation was performed with DCFH-DA fluorophore. Permeability was investigated using HPLC-MS to obtain log kw. Combination therapy was also evaluated using the best compound with gemcitabine. RESULTS: The inhibition of intracellular CP activity by the compounds was confirmed, and the cytostatic effect was established with cell cycle retention in the G1 phase. CP inhibitors were able to reduce cell proliferation by 50% in the clonogenic assay, and the same result was achieved for the migration assay, without any cytotoxic effect. The Neq0554 inhibitor was also efficient to increase the gemcitabine potency in the combination therapy. Physicochemical properties using an artificial membrane model quantified 1.14 ≥ log Kw ≥ 0.75 for all inhibitors (also confirmed using HPLC-MS analysis) along with the identification of intra and extracellular metabolites. Finally, these dipeptidyl nitrile derivatives did not trigger the formation of reactive oxygen species, which is linked to genotoxicity. CONCLUSION: Altogether, these results provide a clear and favorable picture to develop CP inhibitors in pre-clinical assays.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma Ductal Pancreático/tratamiento farmacológico , Inhibidores de Cisteína Proteinasa/farmacología , Dipéptidos/farmacología , Nitrilos/farmacología , Neoplasias Pancreáticas/tratamiento farmacológico , Animales , Antineoplásicos/química , Células 3T3 BALB , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Química Física , Proteasas de Cisteína/metabolismo , Inhibidores de Cisteína Proteinasa/química , Dipéptidos/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células Hep G2 , Humanos , Ratones , Ratones Endogámicos BALB C , Nitrilos/química , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Especies Reactivas de Oxígeno/análisis , Relación Estructura-Actividad
13.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 9): 1195-1200, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30225098

RESUMEN

The title compound, C12H10N4O, comprises a central 1,2,3-triazole ring (r.m.s. deviation = 0.0030 Å) flanked by N-bound 4-cyano-phenyl and C-bound acetyl groups, which make dihedral angles of 54.64 (5) and 6.8 (3)° with the five-membered ring, indicating a twisted mol-ecule. In the crystal, the three-dimensional architecture is sustained by carbonyl-C=O⋯π(triazo-yl), cyano-C≡N⋯π(triazo-yl) (these inter-actions are shown to be attractive based on non-covalent inter-action plots) and π-π stacking inter-actions [inter-centroid separation = 3.9242 (9) Å]. An analysis of the Hirshfeld surface shows the important contributions made by H⋯H (35.9%) and N⋯H (26.2%) contacts to the overall surface, as well as notable contributions by O⋯H (9.9%), C⋯H (8.7%), C⋯C (7.3%) and C⋯N (7.2%) contacts.

14.
Bioorg Med Chem Lett ; 27(22): 5031-5035, 2017 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-29054358

RESUMEN

The effects on potency of cruzain inhibition of replacing a nitrile group with alternative warheads were explored. The oxime was almost an order of magnitude more potent than the corresponding nitrile and has the potential to provide access to the prime side of the catalytic site. Dipeptide aldehydes and azadipeptide nitriles were found to be two orders of magnitude more potent cruzain inhibitors than the corresponding dipeptide nitriles although potency differences were modulated by substitution at P1 and P3. Replacement of the α methylene of a dipeptide aldehyde with cyclopropane led to a loss of potency of almost three orders of magnitude. The vinyl esters and amides that were characterized as reversible inhibitors were less potent than the corresponding nitrile by between one and two orders of magnitude.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa/química , Dominio Catalítico , Catepsina L/química , Catepsina L/metabolismo , Cisteína Endopeptidasas/química , Inhibidores de Cisteína Proteinasa/metabolismo , Dipéptidos/química , Diseño de Fármacos , Cinética , Nitrilos/química , Relación Estructura-Actividad
15.
J Biomol Struct Dyn ; 35(15): 3232-3249, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27809673

RESUMEN

The HQSAR, molecular docking, and ROCS were applied to a data-set of 57 cruzain inhibitors. The best HQSAR model (q2 = .70, r2 = .95, [Formula: see text] = .62, [Formula: see text] = .09 and [Formula: see text] = .26), employing well-balanced, diverse training (40) and test (17) sets, was obtained using atoms (A), bonds (B), and hydrogen (H) as fragment distinctions and 6-9 as fragment sizes. This model was then used to predict the unknown potencies of 121 compounds (the V1 database), giving rise to a satisfactory predictive r2 value of .65 (external validation). By employing an extra external data-set comprising 1223 compounds (the V3 database) either retrieved from the ChEMBL or CDD databases, an overall ROC AUC score well over .70 was obtained. The contribution maps obtained with the best HQSAR model (model 3.4) are in agreement with the predicted binding mode and with the biological potencies of the studied compounds. We also screened these compounds using the ROCS method, a Gaussian-shape volume filter able to identify quickly the shapes that match a query molecule. The area under the curve (AUC) obtained with the ROC curves (ROC AUC) was .72, indicating that the method was very efficient in distinguishing between active and inactive cruzain inhibitors. These set of information guided us to propose novel cruzain inhibitors to be synthesized. Then, the best HQSAR model obtained was used to predict the pIC50 values of these new compounds. Some compounds identified using this method have shown calculated potencies higher than those which have originated them.


Asunto(s)
Antiprotozoarios/química , Cisteína Endopeptidasas/química , Inhibidores de Cisteína Proteinasa/química , Proteínas Protozoarias/química , Área Bajo la Curva , Dominio Catalítico , Simulación del Acoplamiento Molecular , Nitrilos/química , Unión Proteica , Proteínas Protozoarias/antagonistas & inhibidores , Relación Estructura-Actividad Cuantitativa , Curva ROC , Trypanosoma cruzi/enzimología
16.
Eur J Med Chem ; 101: 836-42, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26275603

RESUMEN

The synthesis of a series of 14 new 1-(3-(aryl-4,5-dihydroisoxazol-5-yl)methyl)-4-trihalomethyl-1H-pyrimidin-2-ones from the 1,3-dipolar cycloaddition reaction of 1-allyl-4-(trihalomethyl)pyrimidin-2(1H)-ones with aryl nitrile oxides is described. Also, the antiproliferative activity of the title compounds was tested against five human tumoral cell lines: MCF-7 breast cancer cell line, ER+ (estrogen receptor positive); HepG-2 (hepatoma); T-24 (bladder cancer); HCT-116 cell (colorectal carcinoma); and CACO-2. The preliminary results are promising, since three compounds presented IC50 values below 2 µM, as well as moderate to high selectivity.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Isoxazoles/farmacología , Pirimidinonas/farmacología , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células HEK293 , Humanos , Isoxazoles/síntesis química , Isoxazoles/química , Modelos Moleculares , Estructura Molecular , Pirimidinonas/síntesis química , Pirimidinonas/química , Relación Estructura-Actividad
17.
Braz J Microbiol ; 46(1): 113-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26221095

RESUMEN

A modified colorimetric high-throughput screen based on pH changes combined with an amidase inhibitor capable of distinguishing between nitrilases and nitrile hydratases. This enzymatic screening is based on a binary response and is suitable for the first step of hierarchical screening projects.


Asunto(s)
Aminohidrolasas/análisis , Colorimetría/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Hidroliasas/análisis , Amidohidrolasas/antagonistas & inhibidores , Concentración de Iones de Hidrógeno
18.
Braz. j. microbiol ; Braz. j. microbiol;46(1): 113-116, 05/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-748237

RESUMEN

A modified colorimetric high-throughput screen based on pH changes combined with an amidase inhibitor capable of distinguishing between nitrilases and nitrile hydratases. This enzymatic screening is based on a binary response and is suitable for the first step of hierarchical screening projects.


Asunto(s)
Aminohidrolasas/análisis , Colorimetría/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Hidroliasas/análisis , Amidohidrolasas/antagonistas & inhibidores , Concentración de Iones de Hidrógeno
19.
Braz. J. Microbiol. ; 46(1): 113-116, Jan.- Mar. 2015. tab, graf
Artículo en Inglés | VETINDEX | ID: vti-481370

RESUMEN

A modified colorimetric high-throughput screen based on pH changes combined with an amidase inhibitor capable of distinguishing between nitrilases and nitrile hydratases. This enzymatic screening is based on a binary response and is suitable for the first step of hierarchical screening projects.(AU)


Asunto(s)
Aminohidrolasas/análisis , Colorimetría/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Hidroliasas/análisis , Amidohidrolasas/antagonistas & inhibidores , Concentración de Iones de Hidrógeno
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