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1.
Mol Divers ; 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37670118

RESUMO

The dopamine transporter (DAT), responsible for the regulation of dopaminergic neurotransmission, is implicated in the etiology of several neuropsychiatric disorders which, in turn, have contributed to high rates of disability and numerous deaths in recent years, significantly impacting the global health system. Although the research for new drugs for the treatment of neuropsychiatric disorders has evolved in recent years, the availability of DAT-selective drugs that do not generate the same psychostimulant effects observed in drugs of abuse remains scarce. Therefore, we performed a QSAR study based on a dataset of 36 methylamine derivatives described as DAT inhibitors. The model was obtained based only in descriptors derived from 2D structures, and it was validated and generated satisfactory results considering the metrics used for internal and external validation. Subsequently, a virtual screening step also based on 2D similarity was performed, where it was possible to identify a total of 1157 compounds. After a series of reductions of the set using toxicity filters, applicability domain evaluation, and pharmacokinetic properties in silico assessment, seven hit compounds were selected as the most promising to be used, in future studies, as new scaffolds for the development of new DAT inhibitors.

3.
J Biomol Struct Dyn ; : 1-14, 2023 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-37394802

RESUMO

This study aimed to identify natural bioactive compounds (NBCs) as potential inhibitors of the spike (S1) receptor binding domain (RBD) of the COVID-19 Omicron variant using computer simulations (in silico). NBCs with previously proven biological in vitro activity were obtained from the ZINC database and analyzed through virtual screening, molecular docking, molecular dynamics (MD), molecular mechanics/Poisson-Boltzmann surface area (MM/PBSA), and molecular mechanics/generalized Born surface area (MM/GBSA). Remdesivir was used as a reference drug in docking and MD calculations. A total of 170,906 compounds were analyzed. Molecular docking screening revealed the top four NBCs with a high affinity with the spike (affinity energy <-7 kcal/mol) to be ZINC000045789238, ZINC000004098448, ZINC000008662732, and ZINC000003995616. In the MD analysis, the four ligands formed a complex with the highest dynamic equilibrium S1 (mean RMSD <0.3 nm), lowest fluctuation of the complex amino acid residues (RMSF <1.3), and solvent accessibility stability. However, the ZINC000045789238-spike complex (naringenin-4'-O glucuronide) was the only one that simultaneously had minus signal (-) MM/PBSA and MM/GBSA binding free energy values (-3.74 kcal/mol and -15.65 kcal/mol, respectively), indicating favorable binding. This ligand (naringenin-4'-O glucuronide) was also the one that produced the highest number of hydrogen bonds in the entire dynamic period (average = 4601 bonds per nanosecond). Six mutant amino acid residues formed these hydrogen bonds from the RBD region of S1 in the Omicron variant: Asn417, Ser494, Ser496, Arg403, Arg408, and His505. Naringenin-4'-O-glucuronide showed promising results as a potential drug candidate against COVID-19. In vitro and preclinical studies are needed to confirm these findings.Communicated by Ramaswamy H. Sarma.

4.
Daru ; 31(1): 51-68, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37195402

RESUMO

OBJECTIVES: This scoping review aims to present flavonoid compounds' promising effects and possible mechanisms of action on potential therapeutic targets in the SARS-CoV-2 infection process. METHODS: A search of electronic databases such as PubMed and Scopus was carried out to evaluate the performance of substances from the flavonoid class at different stages of SARS-CoV-2 infection. RESULTS: The search strategy yielded 382 articles after the exclusion of duplicates. During the screening process, 265 records were deemed as irrelevant. At the end of the full-text appraisal, 37 studies were considered eligible for data extraction and qualitative synthesis. All the studies used virtual molecular docking models to verify the affinity of compounds from the flavonoid class with crucial proteins in the replication cycle of the SARS-CoV-2 virus (Spike protein, PLpro, 3CLpro/ MPro, RdRP, and inhibition of the host's ACE II receptor). The flavonoids with more targets and lowest binding energies were: orientin, quercetin, epigallocatechin, narcissoside, silymarin, neohesperidin, delphinidin-3,5-diglucoside, and delphinidin-3-sambubioside-5-glucoside. CONCLUSION: These studies allow us to provide a basis for in vitro and in vivo assays to assist in developing drugs for the treatment and prevention of COVID-19.


Assuntos
COVID-19 , Humanos , Simulação de Acoplamento Molecular , SARS-CoV-2 , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico
5.
Mol Divers ; 27(5): 2217-2238, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36409431

RESUMO

Some important atypical antipsychotic drugs target the serotonergic receptor 2A (5-HT2AR). Currently, new therapeutic strategies are needed to offer faster onset of action with fewer side effects and, therefore, greater efficacy in a substantial proportion of patients with neuropsychological disorders such as Autism and Parkinson. The main objective of this work was to use SBDD methods to identify new hit compounds potentially useful as precursors of novel and selective 5-HT2AR antagonists. A structure-based pharmacophore screening study based on a selective antagonist was carried out in ten databases. The set obtained was refined using molecular docking, and the five most promising compounds were subjected to molecular dynamics simulations. The most stable and promising hit occupied a side pocket present in the 5-HT2AR, a site that can be explored to obtain selective ligands. Simulations against 5-HT2CR and D2R showed that the best hit could not form stable complexes with these targets, strengthening the hypothesis that the hit presents selective binding by the receptor of interest. The selected hits showed some predicted toxicity risk or violated some drug-likeness property. However, it can be concluded that the identified hits are the most promising for performing in vitro assays. Once the presence of activity is confirmed, they could become precursors of optimized and selective antagonists of 5-HT2AR. An SBDD study was carried out to identify new selective 5-HT2AR ligands potentially useful for designing selective atypical antipsychotics.


Assuntos
Antipsicóticos , Humanos , Antipsicóticos/farmacologia , Simulação de Dinâmica Molecular , Simulação de Acoplamento Molecular , Serotonina , Farmacóforo , Ligantes , Ligação Proteica
6.
Inflamm Res ; 71(12): 1489-1500, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36307652

RESUMO

OBJECTIVE AND DESIGN: The current study aimed to summarize the evidence of compounds contained in plant species with the ability to block the angiotensin-converting enzyme 2 (ACE-II), through a scoping review. METHODS: PubMed and Scopus electronic databases were used for the systematic search and a manual search was performed RESULTS: Studies included were characterized as in silico. Among the 200 studies retrieved, 139 studies listed after the exclusion of duplicates and 74 were included for the full read. Among them, 32 studies were considered eligible for the qualitative synthesis. The most evaluated class of secondary metabolites was flavonoids with quercetin and curcumin as most actives substances and terpenes (isothymol, limonin, curcumenol, anabsinthin, and artemisinin). Other classes that were also evaluated were alkaloid, saponin, quinone, substances found in essential oils, and primary metabolites as the aminoacid L-tyrosine and the lipidic compound 2-monolinolenin. CONCLUSION: This review suggests the most active substance from each class of metabolites, which presented the strongest affinity to the ACE-II receptor, what contributes as a basis for choosing compounds and directing the further experimental and clinical investigation on the applications these compounds in biotechnological and health processes as in COVID-19 pandemic.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Tratamento Farmacológico da COVID-19 , Humanos , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Pandemias , Flavonoides , Angiotensinas
7.
Struct Chem ; 33(5): 1691-1706, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35811781

RESUMO

COVID-19, whose etiological agent is the SARS-CoV-2 virus, has caused over 537.5 million cases and killed over 6.3 million people since its discovery in 2019. Despite the recent development of the first drugs indicated for treating people already infected, the great need to develop new anti-SARS-CoV-2 drugs still exists, mainly due to the possible emergence of new variants of this virus and resistant strains of the current variants. Thus, this work presents the results of QSAR and similarity search studies based only on 2D structures from a set of 32 bicycloproline derivatives, aiming to quickly, reproducibly, and reliably identify potentially useful compounds as scaffolds of new major protease inhibitors (Mpro) of the virus. The obtained QSAR model is based only on topological molecular descriptors. The model has good internal and external statistics, is robust, and does not present a chance correlation. This model was used as one of the tools to support the virtual screening stage carried out in the SwissADME web tool. Five molecules, from an initial set of 2695 molecules, proved to be the most promising, as they were within the model's applicability domain and linearity range, with low potential to cause carcinogenic, teratogenic, and reproductive toxicity effects and promising pharmacokinetic properties. These five compounds were then selected as the most competent to generate, in future studies, new anti-SARS-CoV-2 agents with drug-likeness properties suitable for use in therapy.

8.
Phytother Res ; 36(7): 2686-2709, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35355337

RESUMO

Coronavirus disease 2019 (COVID-19) is caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which has a high mortality rate and transmissibility. In this context, medicinal plants have attracted attention due to the wide availability and variety of therapeutic compounds, such as alkaloids, a vast class with several proven pharmacological effects, like the antiviral and anti-inflammatory activities. Therefore, this scoping review aimed to summarize the current knowledge of the potential applicability of alkaloids for treating COVID-19. A systematic search was performed on PubMed and Scopus, from database inception to August 2021. Among the 63 eligible studies, 65.07% were in silico model, 20.63% in vitro and 14.28% clinical trials and observational studies. According to the in silico assessments, the alkaloids 10-hydroxyusambarensine, cryptospirolepine, crambescidin 826, deoxynortryptoquivaline, ergotamine, michellamine B, nigellidine, norboldine and quinadoline B showed higher binding energy with more than two target proteins. The remaining studies showed potential use of berberine, cephaeline, emetine, homoharringtonine, lycorine, narciclasine, quinine, papaverine and colchicine. The possible ability of alkaloids to inhibit protein targets and to reduce inflammatory markers show the potential for development of new treatment strategies against COVID-19. However, more high quality analyses/reviews in this field are necessary to firmly establish the effectiveness/safety of the alkaloids here described.


Assuntos
Alcaloides , Tratamento Farmacológico da COVID-19 , Alcaloides/química , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Antivirais/química , Antivirais/farmacologia , Antivirais/uso terapêutico , Humanos , SARS-CoV-2
9.
BMC Pharmacol Toxicol ; 20(Suppl 1): 76, 2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31852548

RESUMO

BACKGROUND: Chagas disease (CD) is a tropical parasitic disease. Although the number of people infected is very high, the only drugs available to treat CD, nifurtimox (Nfx) and benznidazole, are highly toxic, particularly in the chronic stage of the disease. Coumarins are a large class of compounds that display a wide range of interesting biological properties, such as antiparasitic. Hence, the aim of this work is to find a good antitrypanosomal drug with less toxicity. The use of simple organism models has become increasingly attractive for planning and simplifying efficient drug discovery. Within these models, Caenorhabditis elegans has emerged as a convenient and versatile tool with significant advantages for the toxicological potential identification for new compounds. METHODS: Trypanocidal activity: Forty-two 4-methylamino-coumarins were assayed against the epimastigote form of Trypanosoma cruzi (Tulahuen 2 strain) by inhibitory concentration 50% (IC50). Toxicity assays: Lethal dose 50% (LD50) and Body Area were determined by Caenorhabditis elegans N2 strain (wild type) after acute exposure. Structure-activity relationship: A classificatory model was built using 3D descriptors. RESULTS: Two of these coumarins demonstrated near equipotency to Nifurtimox (IC50 = 5.0 ± 1 µM), with values of: 11 h (LaSOM 266), (IC50 = 6.4 ± 1 µM) and 11 g (LaSOM 231), (IC50 = 8.2 ± 2.3 µM). In C. elegans it was possible to observe that Nfx showed greater toxicity in both the LD50 assay and the evaluation of the development of worms. It is possible to observe that the efficacy between Nfx and the synthesized compounds (11 h and 11 g) are similar. On the other hand, the toxicity of Nfx is approximately three times higher than that of the compounds. Results from the QSAR-3D study indicate that the volume and hydrophobicity of the substituents have a significant impact on the trypanocidal activities for derivatives that cause more than 50% of inhibition. These results show that the C. elegans model is efficient for screening potentially toxic compounds. CONCLUSION: Two coumarins (11 h and 11 g) showed activity against T. cruzi epimastigote similar to Nifurtimox, however with lower toxicity in both LD50 and development of C. elegans assays. These two compounds may be a feasible starting point for the development of new trypanocidal drugs.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Cumarínicos/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Cumarínicos/síntese química , Cumarínicos/química , Cumarínicos/toxicidade , Concentração Inibidora 50 , Dose Letal Mediana , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Tripanossomicidas/síntese química , Tripanossomicidas/química , Tripanossomicidas/toxicidade , Trypanosoma cruzi/crescimento & desenvolvimento
10.
Eur J Med Chem ; 140: 187-199, 2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-28926763

RESUMO

Two series of diaryl-tetrahydrofuran and -furan were synthesised and screened for anti-trypanosomal activity against trypomastigote and amastigote forms of Trypanosoma cruzi, the causative agent of Chagas disease. Based on evidence that modification of a natural product may result in a more effective drug than the natural product itself, and using known neolignan inhibitors veraguensin 1 and grandisin 2 as templates to synthesise simpler analogues, remarkable anti-trypanosomal activity and selectivity were found for 3,5-dimethoxylated diaryl-furan 5c and 2,4-dimethoxylated diaryl-tetrahydrofuran 4e analogues with EC50 0.01 µM and EC50 0.75 µM, respectively, the former being 260-fold more potent than veraguensin 1 and 150-fold better than benznidazole, the current available drugs for Chagas disease treatment. The ability of the most potent anti-trypanosomal compounds to penetrate LLC-MK2 cells infected with T. cruzi amastigotes parasite was tested, which revealed 4e and 5e analogues as the most effective, causing no damage to mammalian cells. In particular, the majority of the derivatives were non-toxic against mice spleen cells. 2D-QSAR studies show the rigid central core and the position of dimethoxy-aryl substituents dramatically affect the anti-trypanosomal activity. The mode of action of the most active anti-trypanosomal derivatives was investigated by exploring the anti-oxidant functions of Trypanothione reductase (TR). As a result, diarylfuran series displayed the strongest inhibition, highlighting compounds 5d-e (IC50 19.2 and 17.7 µM) and 5f-g (IC50 8.9 and 7.4 µM), respectively, with similar or 2-fold higher than the reference inhibitor clomipramine (IC50 15.2 µM).


Assuntos
Inibidores Enzimáticos/farmacologia , Furanos/farmacologia , Lignanas/farmacologia , NADH NADPH Oxirredutases/antagonistas & inibidores , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Furanos/síntese química , Furanos/química , Lignanas/química , Macaca mulatta , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , NADH NADPH Oxirredutases/metabolismo , Testes de Sensibilidade Parasitária , Relação Quantitativa Estrutura-Atividade , Tripanossomicidas/síntese química , Tripanossomicidas/química , Trypanosoma cruzi/metabolismo
11.
J Hazard Mater ; 304: 233-41, 2016 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-26551227

RESUMO

Aromatic sulfones comprise a class of chemicals used in agrochemical and pharmaceutical industries and as floatation and extractant agents in petrochemical and metallurgy industries. In this study, new QSA(P)R studies were carried out to predict the toxicity against Vibrio fischeri of a set of 52 aromatic sulfones. The same approach was used to evaluate the relationship between these endpoint and the water solubility, another important environmental endpoint. The study resulted in models of good statistical quality and mechanistic interpretation with a possible correlation between the two endpoints, but the toxic effect is also likely to depend on other physicochemical properties. The use of the PLS2, a method not commonly used in QSA(P)R studies, also produced models of greater reliability, and the relationship between the two endpoints was reinforced to some degree. These results are useful for better understanding the process by which these compounds exert their environmental toxicity, thus aiding in the development of industrially useful compounds with less potential environmental damage.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Ácidos Carboxílicos/toxicidade , Modelos Teóricos , Sulfonas/toxicidade , Ácidos Carboxílicos/química , Relação Quantitativa Estrutura-Atividade , Sulfonas/química
12.
Phys Chem Chem Phys ; 18(2): 1341-3, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26648439

RESUMO

Correction for 'A structure-activity relationship study of the toxicity of ionic liquids using an adapted Ferreira-Kiralj hydrophobicity parameter' by Eduardo Borges de Melo et al., Phys. Chem. Chem. Phys., 2015, 17, 4516-4523.

13.
Bioorg Med Chem ; 23(21): 6815-26, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26476667

RESUMO

The current treatment of Chagas disease is based on the use of two drugs, nifurtimox and benznidazole, which present limited efficacy in the chronic stage of the disease and toxic side effects. Although some progress has been made in the development of new drugs to treat this disease, the discovery of novel compounds is urgently required. In this work we report the synthesis and biological evaluation of 1,2,3-triazole-based analogues of benznidazole. A small series of 27 compounds was successfully synthesized via microwave-assisted copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) and ruthenium-catalyzed azide-alkyne cycloaddition (RuAAC) from N-benzyl-2-azidoacetamide (1) and a set of commercial terminal alkynes. Analogues 24 (IC50 40 µM) and 28 (IC50 50 µM) showed comparable activities to benznidazole (IC50 34 µM) against trypomastigote form and analogue 15 (IC50 7 µM) was found to be the most active. Regarding the cytotoxicity assessment of the series, most compounds were not cytotoxic. This work shows that the designed strategy is efficiently capable of generating novel benzindazole analogues and reveals one analogue is more active than benznidazole.


Assuntos
Nitroimidazóis/química , Triazóis/química , Tripanossomicidas/química , Catálise , Química Click , Cobre/química , Reação de Cicloadição , Micro-Ondas , Nitroimidazóis/síntese química , Nitroimidazóis/farmacologia , Rutênio/química , Relação Estrutura-Atividade , Tripanossomicidas/síntese química , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos
14.
Phys Chem Chem Phys ; 17(6): 4516-23, 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25583131

RESUMO

The Ferreira-Kiralj hydrophobicity parameter Wc is a number fraction of hydrophobic carbon atoms and can be regarded as a constitutional descriptor since its calculation depends only on the number of polar and nonpolar carbons in a compound. Hydrophobicity is important to the toxicity of ionic liquids (ILs), which are salts by nature. Herein, a descriptor for this property was calculated using a simple adaptation of the type of polar carbon atoms included (WcAdap) to explore the possibility of its use in quantitative structure-activity relationship (QSAR) studies of ILs. The resulting model was tested using a database of ILs with toxicity against the Leukemia rat cell line IPC-81. Two other models were constructed using Crippen log P and Mannhold log P descriptors, which are both available in the free program PaDEL. The use of WcAdap led to a better and more indicative model. Thus, WcAdap may be a suitable molecular descriptor for the hydrophobicity of ILs in QSAR studies.


Assuntos
Líquidos Iônicos/toxicidade , Animais , Linhagem Celular Tumoral , Interações Hidrofóbicas e Hidrofílicas , Relação Quantitativa Estrutura-Atividade , Ratos
15.
J Mol Graph Model ; 54: 19-31, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25244636

RESUMO

In the present study, we performed a multivariate quantitative structure-activity relationship (QSAR) analysis of 52 prodiginines with antimalarial activity. Variable selection was based on the genetic algorithm (GA) and ordered predictor selection (OPS) approaches, and the models were built using the multiple linear regression (MLR) and partial least squares (PLS) regression methods. The leave-N-out crossvalidation and y-randomization tests showed that the models were robust and free from chance correlation. The mechanistic interpretation of the results was supported by earlier findings. In addition, the comparison of our models with those previously described indicated that the OPS/PLS-based model had a higher quality of external prediction. Thus, this study provides a comprehensive approach to the evaluation of the antimalarial activity of prodiginines, which may be used as a support tool in designing new therapeutic agents for malaria.


Assuntos
Antimaláricos/química , Prodigiosina/análogos & derivados , Algoritmos , Prodigiosina/química , Relação Quantitativa Estrutura-Atividade , Relação Estrutura-Atividade
16.
Water Res ; 53: 191-9, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24525068

RESUMO

The collection of data to study the damage caused by pesticides to the environment and its ecosystems is slowly acquired and costly. Large incentives have been established to encourage research projects aimed at building mathematical models for predicting physical, chemical or biological properties of environmental interest. The organic carbon normalized soil sorption coefficient (K(oc)) is an important physicochemical property used in environmental risk assessments for compounds released into the environment. Many models for predicting logK(oc) that have used the parameters logP or logS as descriptors have been published in recent decades. The strong correlation between these properties (logP and logS) prevents them from being used together in multiple linear regressions. Because the sorption of a chemical compound in soil depends on both its water solubility and its water/organic matter partitioning, we assume that models capable of combining these two properties can generate more realistic results. Therefore, the objective of this study was to propose an alternative approach for modeling logK(oc), using a simple descriptor of solubility, here designated as the logarithm of solubility corrected by octanol/water partitioning (logS(P)). Thus, different models were built with this descriptor and with the conventional descriptors logP and logS, alone or associated with other explanatory variables representing easy-to-interpret physicochemical properties. The obtained models were validated according to current recommendations in the literature, and they were compared with other previously published models. The results showed that the use of logS(p) instead of conventional descriptors led to simple models with greater statistical quality and predictive power than other more complex models found in the literature. Therefore, logS(P) can be a good alternative to consider for the modeling of logK(oc) and other properties that relate to both solubility and water/organic matter partitioning.


Assuntos
Modelos Teóricos , Praguicidas/química , Poluentes do Solo/química , Solo/química , Monitoramento Ambiental , Octanóis/química , Solubilidade , Água/química
17.
Water Res ; 47(15): 5751-9, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23886539

RESUMO

Collecting data on the effects of pesticides on the environment is a slow and costly process. Therefore, significant efforts have been focused on the development of models that predict physical, chemical or biological properties of environmental interest. The soil sorption coefficient normalized to the organic carbon content (Koc) is a key parameter that is used in environmental risk assessments. Thus, several log Koc prediction models that use the hydrophobic parameter log P as a descriptor have been reported in the literature. Often, algorithms are used to calculate the value of log P due to the lack of experimental values for this property. Despite the availability of various algorithms, previous studies fail to describe the procedure used to select the appropriate algorithm. In this study, models that correlate log Koc with log P were developed for a heterogeneous group of nonionic pesticides using different freeware algorithms. The statistical qualities and predictive power of all of the models were evaluated. Thus, this study was conducted to assess the effect of the log P algorithm choice on log Koc modeling. The results clearly demonstrate that the lack of a selection criterion may result in inappropriate prediction models. Seven algorithms were tested, of which only two (ALOGPS and KOWWIN) produced good results. A sensible choice may result in simple models with statistical qualities and predictive power values that are comparable to those of more complex models. Therefore, the selection of the appropriate log P algorithm for modeling log Koc cannot be arbitrary but must be based on the chemical structure of compounds and the characteristics of the available algorithms.


Assuntos
Praguicidas/química , Poluentes do Solo/química , Algoritmos , Interações Hidrofóbicas e Hidrofílicas , Modelos Teóricos
18.
Artigo em Inglês | LILACS | ID: lil-658491

RESUMO

In Brazil, in order for a pharmaceutical company to register a drug form as generic or ?similar? with the Brazilian food and drug agency (Anvisa), it must be proved bioequivalent to its innovatory branded form (reference drug). This requires comparative trials, carried out in conformity with official compendia (Brazilian Pharmacopeia or another officially recognized code). Additionally, according to the Anvisa resolution RDC 31/2010, the dissolution profile of the drug must be tested and compared with that of the branded reference, as a benchmark of quality. The aim of this study was to assess the quality of 500 mg sodium metamizole (dipyrone) tablets produced by seven different laboratories in Brazil: three generic drugs (G1, G2, G3), three (branded) similar drugs (S1, S2, S3) and their reference branded product (Novalgina®, Sanofi-Aventis, drug R). All tests were carried out by methods specified in the Brazilian Pharmacopeia 4th edition (Farmacopeia Brasileira IV). The following tests were performed: uniformity of mass, friability, disintegration time, hardness, assay, uniformity of dosage units, salicylic acid limit assay, dissolution and identification. The dissolution profile was also recorded, as recommended in RDC 31/2010. Whereas every sample was approved in all the Farmacopeia Brasileira IV tests, the results in the dissolution profile test showed that four of the test drugs (G1, G2, S1 and S2) were not pharmaceutically equivalent to drug R. Thus, only drugs G3 and S3 showed dissolution profiles similar to that of drug R and the other four drugs could not be considered equivalent to it and were not approved.


No Brasil, para que uma indústria farmacêutica registre um produto como genérico ou similar, o medicamento deve ser bioequivalente a seu medicamento de referência. Isto requer a realização de estudos comparativos, seguindo um compêndio oficial (Farmacopeia Brasileira ou outra reconhecida oficialmente). Além disso, de acordo com a RDC 31/2010, também deve ser realizado o estudo do perfil de dissolução em relação ao seu medicamento de referência. Este estudo teve como objetivo avaliar a qualidade de comprimidos de metamizol sódico (ou dipirona) com teor de 500mg produzidos por sete diferentes laboratórios brasileiros: três medicamentos genéricos (G1, G2, G3), três similares (S1, S2, S3) e o medicamento de referência (Novalgina®, Sanofi-Aventis, R). Todos os testes seguiram os métodos descritos na Farmacopeia Brasileira IV. Os seguintes ensaios foram realizados: uniformidade de massa, friabilidade, tempo de desintegração, dureza, doseamento, uniformidade de doses unitárias, ensaio limite de ácido salicílico e identificação. O perfil de dissolução foi realizado como recomendado pela RDC 31/2010. Apesar das amostras terem sido aprovadas em todos os ensaios farmacopéicos, os resultados do perfil de dissolução indicaram que quatro medicamentos (G1, G2, S1 e S2) não são equivalentes farmacêuticos de R. Apenas G3 e S3 mostraram perfis similares a R. Assim, quatro medicamentos foram reprovados.


Assuntos
Dipirona , Avaliação de Medicamentos , Medicamentos Genéricos/farmacocinética , Medicamentos Similares , Solubilidade , Brasil
19.
Sci Pharm ; 80(2): 265-81, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22896815

RESUMO

A multivariate PLS-QSAR study with a data set of 31 cinnamoyl pyrrolidine derivatives described as type 2 matrix metalloproteinases (MMP-2) inhibitors is presented in this paper. The variable selection was performed with the Ordered Predictors Selection (OPS) algorithm. The PLS model presented six descriptors and three Latent Variables (LV) that cumulated 71.845% of variance. Leave-N-out (LNO) cross validation and y-randomization tests showed that the model presented robustness and no chance correlation, respectively. The descriptors indicated that MMP-2 inhibition depends mainly on the electronic properties of the compounds. The model obtained can be useful as a support tool in the design of new MMP-2 inhibitors.

20.
Biosci. j. (Online) ; 28(3): 484-493, may/june 2012. ilus, graf, tab
Artigo em Português | LILACS | ID: biblio-912627

RESUMO

Um dos ensaios descritos na Farmacopéia Brasileira para determinação do fármaco anti-hipertensivo atenolol como matéria prima e em comprimidos utiliza espectrofotometria ultravioleta (UV). Porém, o solvente utilizado é o metanol, um agente químico inflamável e tóxico, cujos resíduos químicos são de difícil tratamento. Portanto, é interessante o desenvolvimento de métodos analíticos que sejam mais seguros e ambientalmente adequados. Considerando que o atenolol é solúvel em soluções ácidas diluídas, foi avaliado o uso de ácido clorídrico 0,01 mol.L -1 como um método alternativo. Para isto, foi realizada a validação do novo método avaliando sua linearidade, especificidade, seletividade, intervalo, limite de quantificação e detecção, precisão, exatidão e robustez. Todas as figuras de mérito mostraram-se dentro dos limites recomendados pela Agência Nacional de Vigilância Sanitária (Anvisa). A comparação com o método original mostrou equivalência estatística entre os métodos. Assim, o método mostrou-se adequado como um procedimento mais seguro e ambientalmente adequado para as etapas de controle de qualidade relacionadas a produção de medicamentos a base de atenolol pelas indústrias farmacêuticas.


One of the tests described in the Farmacopéia Brasileira 5ª Edição (F. Bras. V) to assay the antihypertensive drug atenolol as raw material and tablets use ultraviolet spectrophotometry (UV). However, the solvent is methanol, a flammable and toxic chemical agent whose chemical residues are not easily manageable. Therefore, it is necessary to develop analytical methods that are safer and environmentally appropriate. Considering that atenolol is soluble in dilute acid solutions, the use of hydrochloric acid 0.01 mol L-1 as solvent was evaluated as an alternative method. For this, it was performed a validation of the new method assessing its linearity, specificity, selectivity, range, limit of quantification and detection, precision, accuracy and robustness. All figures of merit were within the limits recommended by the Agência Nacional de Vigilância Sanitária (ANVISA). The comparison with the original method showed statistical equivalence between the procedures. Thus, the new method was considered suitable as a safer and more environmentally appropriate for quality control of the production of drugs with atenolol by pharmaceutical industries.


Assuntos
Atenolol , Espectrofotometria , Resíduos Químicos , Metanol , Química Verde
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