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1.
Molecules ; 28(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37687165

RESUMO

Surfactants are amphiphilic molecules and one of the most versatile products of the chemical industry. They can be absorbed at the air-water interface and can align themselves so that the hydrophobic part is in the air while the hydrophilic part is in water. This alignment lowers the surface or interfacial tension. Gemini surfactants are a modern variety of surfactants with unique properties and a very wide range of potential applications. Hexamethylene-1,6-bis(N-dodecyl-N,N-dimethylammonium bromide) is one such representative compound that is a better alternative to a single analogue. It shows excellent surface, antimicrobial, and anticorrosion properties. With a highly efficient synthetic method and a good ecological profile, it is a potential candidate for numerous applications, including biomedical applications.

2.
Molecules ; 27(19)2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36235201

RESUMO

(1) Background: Encapsulation of surfactants is an innovative approach that allows not only protection of the active substance, but also its controlled and gradual release. This is primarily used to protect metallic surfaces against corrosion or to create biologically active surfaces. Gemini surfactants are known for their excellent anticorrosion, antimicrobial and surface properties; (2) Methods: In this study, we present an efficient methods of preparation of encapsulated gemini surfactants in form of alginate and gelatin capsules; (3) Results: The analysis of infrared spectra and images of the scanning electron microscope confirm the effectiveness of encapsulation; (4) Conclusions: Gemini surfactants in encapsulated form are promising candidates for corrosion inhibitors and antimicrobials with the possibility of protecting the active substance against environmental factors and the possibility of controlled outflow.


Assuntos
Anti-Infecciosos , Tensoativos , Alginatos , Corrosão , Gelatina , Tensoativos/farmacologia
3.
Molecules ; 26(19)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34641303

RESUMO

Due to their large possibility of the structure modification, alkylammonium gemini surfactants are a rapidly growing class of compounds. They exhibit significant surface, aggregation and antimicrobial properties. Due to the fact that, in order to achieve the desired utility effect, the minimal concentration of compounds are used, they are in line with the principle of greenolution (green evolution) in chemistry. In this study, we present innovative synthesis of the homologous series of gemini surfactants modified at the spacer by the ether group, i.e., 3-oxa-1,5-pentane-bis(N-alkyl-N,N-dimethylammonium bromides). The critical micelle concentrations were determined. The minimal inhibitory concentrations of the synthesized compounds were determined against bacteria Escherichia coli ATCC 10536 and Staphylococcus aureus ATCC 6538; yeast Candida albicans ATCC 10231; and molds Aspergillus niger ATCC 16401 and Penicillium chrysogenum ATCC 60739. We also investigated the relationship between antimicrobial activity and alkyl chain length or the nature of the spacer. The obtained results indicate that the synthesized compounds are effective microbicides with a broad spectrum of biocidal activity.


Assuntos
Anti-Infecciosos/farmacologia , Compostos de Amônio Quaternário/farmacologia , Tensoativos/farmacologia , Anti-Infecciosos/química , Aspergillus niger/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Química Verde , Micelas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Penicillium chrysogenum/efeitos dos fármacos , Compostos de Amônio Quaternário/química , Staphylococcus aureus/efeitos dos fármacos , Tensoativos/química
4.
Molecules ; 25(18)2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899824

RESUMO

A series of 21 azapolymethylene gemini surfactants were obtained. The synthesis of the title surfactants in one- or two-step reaction proceeds with good yields. The structure and the purity of the synthesized compounds were determined by 1H and 13C NMR, ESI-MS spectra, and elemental analysis. Moreover, 2D COSY, HMBC, and HSQC spectra were performed. The minimal inhibitory concentrations (MIC) of the synthesized compounds were determined against fungi: Candida albicans, Aspergillus niger, Penicillium chrysogenum and bacteria: Escherichia coli,Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis. Also, the critical micelle concentrations (CMC) were determined. The relationship between antimicrobial and surface activity and surfactant structure has been determined.


Assuntos
Anti-Infecciosos/farmacologia , Compostos Aza/farmacologia , Tensoativos/farmacologia , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Compostos Aza/síntese química , Compostos Aza/química , Bactérias/efeitos dos fármacos , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Fungos/efeitos dos fármacos , Micelas , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Tensoativos/síntese química , Tensoativos/química
5.
Bioelectrochemistry ; 128: 252-262, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31048108

RESUMO

Biocorrosion is an important type of corrosion which leads to economic losses across oil and gas industries, due to increased monitoring, maintenance, and a reduction in platform availability. Ideally, a chemical compound engineered to mitigate against biocorrosion would possess both antimicrobial properties, as well as efficient corrosion inhibition. Gemini surfactants have shown efficacy in both of these properties, however there still remains a lack of electrochemical information regarding biocorrosion inhibition. The inhibition of corrosion and biocorrosion, by cationic gemini surfactants, of carbon steel was investigated. The results showed that the inhibition efficiency of the gemini surfactants was high (consistently >95%), even at low concentrations. Gemini surfactants also showed strong antimicrobial activity, with a minimum inhibitory concentration (0.018 mM). Corrosion inhibition was investigated by electrochemical impedance spectroscopy (EIS) and linear polarisation resistance (LPR), with biocorrosion experiments carried out in an anaerobic environment. Surface morphology was analysed using scanning electron microscopy (SEM).


Assuntos
Antibacterianos/farmacologia , Biofilmes , Corrosão , Compostos de Amônio Quaternário/farmacologia , Aço/química , Tensoativos/farmacologia , Espectroscopia Dielétrica , Microscopia Eletrônica de Varredura
6.
J Hazard Mater ; 371: 108-114, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-30849564

RESUMO

New cleavable oligomeric cationic surfactants containing ester groups susceptible to hydrolysis between the hydrocarbon tails and the hydrophilic moiety have been synthesized and their biodegradability and aquatic toxicity examined. Aerobic biodegradability was evaluated by applying a standard method for ready biodegradability, the CO2 Headspace test. Aquatic toxicity was assessed by means of the acute toxicity test with Daphnia. Cleavable oligomeric cationic surfactants undergo a significant biodegradation extent (31-52%) as compared to dimeric surfactants without ester groups that showed null degradation in previous works. However, they do not attain the threshold of ultimate degradation required (60%) to be classed as easily biodegradable chemicals. On the other hand, the introduction of cleavable groups in the surfactant hydrophobic chains reduces the toxic effects on the microorganisms responsible for degradation observed for conventional alkyl ammonium dimeric surfactants. Acute toxicity values of betainate cationic oligomeric surfactants to Daphnia magna, IC50-48 h, varies from 1.5 to 50 mg/L. Aquatic toxicity of oligomeric cationic surfactants depends on their hydrophobicity and increases regularly with the alkyl chain length. However, whether the surfactant is a dimeric or a trimeric betaine ester does not affect their acute toxicity to crustacean.


Assuntos
Betaína/metabolismo , Betaína/toxicidade , Polímeros/química , Tensoativos/toxicidade , Poluentes Químicos da Água/metabolismo , Animais , Biodegradação Ambiental , Cátions , Daphnia/efeitos dos fármacos , Tensoativos/química , Poluentes Químicos da Água/toxicidade
7.
BMC Cancer ; 18(1): 213, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29466973

RESUMO

BACKGROUND: Aberrant crypt foci (ACF) are commonly considered the early pre-cancerous lesions that can progress to colorectal cancer (CRC). The available literature data reveal that age, dietary factors and lifestyle can affect the development of several dozen percentages of malignant tumours, including CRC. In the present study, an attempt was made to assess the incidence and growth dynamics of ACF and to determine whether the type of diet affected the development and number of AFC. METHODS: Colonoscopy combined with rectal mucosa staining with 0.25% methylene blue was performed in 131 patients. On the day of examination, each patient completed a questionnaire regarding epidemiological data. According to their numbers, colorectal ACF were divided into three groups. The findings were analysed statistically. The Student's t test and the U test were applied in order to determine the significance of differences of means and frequency of events in both groups. Statistica 7.1 and Excel 2010 were used. RESULTS: The single ACF occur in the youngest individuals (ACF < 5). Since the age of 38 years, the number of ACF gradually increases to show a decreasing tendency since the age of 60 years. The number of 5 < ACF < 10 occurs slightly later, since the age of 50 years, and dynamically increases reaching the maximum at the age of 62 years, subsequently the increase is proportional. ACF > 10 occur at a more advanced age (55 years) and their number gradually increases with age. The maximum number is observed at the age of 77 years. In individuals not using high-fibre diets and with high intake of red meat, the probability of higher numbers of ACF increases. The probability of higher numbers of ACF (5 < ACF10) was observed in patients with colon diverticula. In patients with higher BMI, the number of ACF is higher. CONCLUSION: Age significantly affects the number of colorectal ACF. The types of foods consumed can considerably increase the risk of colorectal ACF, which is particularly visible in individuals who do not regularly use high-fibre diets, those obese and with colon diverticula.


Assuntos
Focos de Criptas Aberrantes/epidemiologia , Focos de Criptas Aberrantes/etiologia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Dieta , Focos de Criptas Aberrantes/diagnóstico , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biópsia , Colonoscopia , Neoplasias Colorretais/diagnóstico , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas , Medição de Risco , Fatores de Risco
8.
Molecules ; 22(11)2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-29068383

RESUMO

New dimeric, trimeric and tetrameric quaternary ammonium salts were accomplished by reaction of tertiary alkyldimethyl amines with appropriate bromomethylbenzene derivatives. A series of new cationic surfactants contain different alkyl chain lengths (C4-C18), aromatic spacers and different numbers of quaternary nitrogen atoms. The structure of the products was confirmed by spectral analysis (FT-IR, ¹H-NMR, 13C-NMR and 2D-NMR), mass spectroscopy (ESI-MS), elemental analysis, as well as PM5 semiempirical methods. Compound (21) was also analyzed using X-ray crystallography. Critical micelle concentration (CMC) of 1,4-bis-[N-(1-alkyl)-N,N-dimethylammoniummethyl]benzene dibromides (3-9) was determined to characterize the aggregation behavior. The antimicrobial properties of novel QACs (Quaternary Ammonium Salts) were examined to set their minimal inhibitory concentration (MIC) values against fungi Aspergillus niger, Candida albicans, Penicillium chrysogenum and bacteria Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Compostos de Amônio Quaternário/síntese química , Compostos de Amônio Quaternário/farmacologia , Anti-Infecciosos/química , Aspergillus niger/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Compostos de Amônio Quaternário/química , Relação Estrutura-Atividade
9.
PLoS One ; 11(2): e0148286, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26886097

RESUMO

Colorectal cancer (CRC) is the second most common cause of death worldwide. According to the theory by Vogelstein, colorectal carcinogenesis involves a series of successive changes in the normal colonic mucosa, starting with excessive proliferation and focal disorders of intestinal crypts, followed by adenoma and its subsequent malignant transformation. The first identifiable changes in CRC carcinogenesis are aberrant crypt foci (ACF). ACF are invisible during routine colonoscopy yet are well identifiable in chromoendoscopy using methylene blue or indigo carmine. High-resolution colonoscopes are used for assessment of ACF. The aim of the present study was to evaluate the usefulness of standard-resolution colonoscopy for identification of rectal ACF. The following parameters were evaluated: duration of chromoendoscopy of a given rectal segment, type of ACF, sensitivity and specificity of endoscopy combined with histopathological evaluation. The mean duration of colonoscopy and chromoendoscopy was 26.8 min. In the study population, typical ACF were found in 73 patients (p = 0.489), hyperplastic ACF in 49 (p = 0.328), and dysplastic ACF in 16 patients (p = 0.107). Mixed ACF were observed in 11 individuals (p = 0.073). The sensitivity of the method was found to be 0.96 whereas its specificity 0.99. Identification of rectal ACF using standard-resolution colonoscopy combined with rectal mucosa staining with 0.25% methylene blue is characterised by high sensitivity and specificity.


Assuntos
Focos de Criptas Aberrantes/diagnóstico , Colonoscópios , Reto/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Adulto Jovem
10.
Acta Chim Slov ; 62(1): 15-27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25830956

RESUMO

The structure of seven bromoacetic substituted derivatives of bile acids are characterized by 1H MMR, 13C NMR, 2D NMR, FT-IR and mass spectrometry (ESI-MS) as well as PM5 semiempirical and B3LYP ab initio methods. Estimation of the pharmacotherapeutic potential has been accomplished for the synthesized compounds on the basis of Prediction of Activity Spectra for Substances (PASS).


Assuntos
Ácidos e Sais Biliares/química , Hidrocarbonetos Bromados/química , Teoria Quântica , Ácidos e Sais Biliares/síntese química , Configuração de Carboidratos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Molecules ; 19(7): 9419-34, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24995925

RESUMO

New dimeric quaternary alkylammonium conjugates of sterols were obtained by two step reactions of ergosterol, cholesterol and cholestanol with bromoacetic acid bromide, followed by bimolecular nucleophilic substitution with N,N,N',N'-tetramethyl-1,3-propanediamine, N,N,N',N'',N''-pentamethyldiethylenetriamine and 3,3'-iminobis- (N,N-dimethylpropylamine). The product structures were confirmed by spectral (1H-NMR, 13C-NMR, FT-IR) analysis, mass spectrometry (ESI-MS) and PM5 semiempirical methods. Additionally in silico studies have been conducted for the synthesized compounds on the basis of Prediction of Activity Spectra for Substances (PASS).


Assuntos
Compostos de Amônio Quaternário/síntese química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Compostos de Amônio Quaternário/química , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Molecules ; 19(4): 4212-33, 2014 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-24705565

RESUMO

New quaternary 3-phthalimidopropylammonium conjugates of steroids were obtained by reaction of sterols (ergosterol, cholesterol, cholestanol) and bile acids (lithocholic, deoxycholic, cholic) with bromoacetic acid bromide to give sterol 3ß-bromoacetates and bile acid 3α-bromoacetates, respectively. These intermediates were subjected to nuclephilic substitution with N,N-dimethyl-3-phthalimidopropylamine to give the final quaternary ammonium salts. The structures of products were confirmed by spectral (1H-NMR, 13C-NMR, and FT-IR) analysis, mass spectrometry (ESI-MS, MALDI) as well as PM5 semiempirical methods and B3LYP ab initio methods. Estimation of the pharmacotherapeutic potential has been accomplished for synthesized compounds on the basis of Prediction of Activity Spectra for Substances (PASS).


Assuntos
Ácidos e Sais Biliares/química , Inibidores Enzimáticos/síntese química , Compostos de Amônio Quaternário/síntese química , Software , Esteróis/química , Inibidores Enzimáticos/química , Estrutura Molecular , Ftalimidas/química , Compostos de Amônio Quaternário/química , Relação Estrutura-Atividade , Interface Usuário-Computador
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 128: 773-80, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24699296

RESUMO

The selenoanalogue of nicotine has been synthesized and characterized by spectroscopic and X-ray diffraction methods. The crystals of selenonicotine are isomorphic with the thionicotine homologue and consist of molecules engaged in columnar π⋯π stacking interactions between antiparallely arranged pyridine moieties. These interactions, absent in other crystals containing nicotine fragments, seem to be induced by the presence of a lactam group. The molecular structures in the vacuum of the oxo-, thio- and selenonicotine homologues have been calculated by the DFT method and compared with the available X-ray data. The delocalized structure of thionicotine is stabilized by intramolecular C-H⋯S hydrogen bond, which becomes weaker in the partial zwitterionic resonance structure of selenonicotine in favor of multiple C-H⋯Se intermolecular hydrogen-bonds. The calculated data allow a complete assignment of vibration modes in the solid state FTIR spectra. The (1)H and (13)C NMR chemical shifts were calculated by the GIAO method with B3LYP/6-311G(3df) level. A comparison between experimental and calculated theoretical results indicates that the density functional B3LYP method provided satisfactory results for predicting FTIR, (1)H, (13)C NMR spectra properties.


Assuntos
Lactamas/química , Lactamas/síntese química , Modelos Moleculares , Nicotina/química , Nicotina/síntese química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
14.
Acta Chim Slov ; 61(1): 39-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24664325

RESUMO

3-(3-Dimethylammonio)propylammonio propanoate bromide (1), 4-(3-dimethylammonio)propylammonio butanoate bromide (2), and 5-(3-dimethylammonio)propylammonio pentanoate bromide (3) have been obtained in reaction of 1,1-dimethyl-1,3-propylenediamine with 3-bromopropionic acid, ethyl 4-bromobutyrate and 5-bromovaleric acid, respectively. The products have been characterized by FTIR, Raman and NMR spectroscopy. Also B3LYP calculations have been carried out. The screening constants for 13C and 1H atoms have been calculated by the GIAO/B3LYP/6-311G(d,p) approach and analyzed. Theoretical vibrational parameters are compared with obtained experimental parameters. Estimation of the pharmacotherapeutic potential has been accomplished for the synthesized compounds on the basis of Prediction of Activity Spectra for Substances (PASSs).


Assuntos
Aminoácidos/química , Aminoácidos/síntese química , Compostos de Amônio/química , Teoria Quântica , Aminoácidos/farmacologia , Técnicas de Química Sintética , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Molecules ; 19(2): 2557-70, 2014 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-24566321

RESUMO

A novel method for the synthesis of bile acid derivatives has been developed using "click chemistry". Intermolecular 1,3-dipolar cycloaddition of the propargyl ester of bile acids and azide groups of 1,3,5-tris(azidomethyl)benzene gave a new quasi-podands with 1,2,3-triazole rings. The structures of the products were confirmed by spectral (1H-NMR, 13C-NMR, and FT-IR) analysis, mass spectrometry and PM5 semiempirical methods. Estimation of the pharmacotherapeutic potential has been accomplished for synthesized compounds on the basis of Prediction of Activity Spectra for Substances (PASS).


Assuntos
Azidas/química , Ácidos e Sais Biliares/química , Triazóis/química , Ácidos e Sais Biliares/síntese química , Química Click , Espectrometria de Massas , Modelos Teóricos , Triazóis/síntese química
16.
Molecules ; 18(12): 14961-76, 2013 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24317524

RESUMO

New quaternary alkylammonium conjugates of steroids were obtained by two step reaction of sterols (ergosterol, cholesterol, dihydrocholesterol) with bromoacetic acid bromide, followed by bimolecular nucleophilic substitution with a long chain tertiary alkylamine. The structures of products were confirmed by spectral (1H-NMR, 13C-NMR, and FT-IR) analysis, mass spectrometry and PM5 semiempirical methods. The pharmacotherapeutic potential of synthesized compounds has been estimated on the basis of Prediction of Activity Spectra for Substances (PASS).


Assuntos
Compostos de Amônio Quaternário/química , Esteróis/química , Técnicas de Química Combinatória , Lanosterol , Espectrometria de Massas , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Compostos de Amônio Quaternário/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier
17.
J Electromyogr Kinesiol ; 23(5): 1150-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23880234

RESUMO

The purpose of this study was to investigate whether age-related changes in motor unit (MU) contractile properties are reflected in parameters of motor unit action potentials (MUAPs). MUs of the medial gastrocnemius muscle were functionally isolated in anaesthetized Wistar rats. A control group of young animals (5-10mo) was compared to two groups of old rats (24-25mo and 28-30mo). The basic contractile properties of MUs as well as the amplitude, total duration, peak-to-peak time, and number of turns within MUAPs were measured. Effects of aging were mainly observed for fast fatigable MUs (a prolongation of MUAPs and increased number of turns). The MUAP amplitude did not change significantly with aging in either MU type, but it correlated to the twitch or tetanic forces, which tended to increase with age, especially for slow MUs. We concluded that the prolongation of MUAPs and the greater incidence of signal turns was probably a result of a decrease in muscle fiber conduction velocity and/or an increase in their dispersion, and enlargement of MU territories - presumably caused by axonal sprouting of surviving motoneurons. The latter might also be responsible for the observed age-related tendency for a increase in MUAP amplitudes in slow MUs.


Assuntos
Potenciais de Ação/fisiologia , Envelhecimento/fisiologia , Contração Isométrica/fisiologia , Neurônios Motores/fisiologia , Músculo Esquelético/fisiologia , Junção Neuromuscular/fisiologia , Transmissão Sináptica/fisiologia , Animais , Masculino , Músculo Esquelético/inervação , Ratos , Ratos Wistar
18.
Molecules ; 16(1): 319-35, 2011 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-21266945

RESUMO

Hexamethylene-1,6-bis-(N,N-dimethyl-N-dodecylammonium bromide), pentamethylene-1,5-bis(N,N-dimethyl-N-dodecylammonium bromide), tetramethylene-1,4-bis(N,N-dimethyl-N-dodecylammonium bromide), trimethylene-1,3-bis(N,N-dimethyl-N-dodecylammonium bromide) and ethylene-1,2-bis(N,N-dimethyl-N-dodecylammonium bromide) have been obtained and characterized by FTIR and NMR spectroscopy. DFT calculations have also been carried out. The optimized bond lengths, bond angles and torsion angles calculated by Hartree-Fock/3-21G(d,p) approach have been presented. MIC values for A. niger, P. chrysogenum, C. albicans have been determined and the relationship between MIC and spacer length has been discussed.


Assuntos
Antifúngicos/síntese química , Antifúngicos/farmacologia , Compostos de Amônio Quaternário/síntese química , Compostos de Amônio Quaternário/farmacologia , Antifúngicos/química , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos de Amônio Quaternário/química , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Molecules ; 15(8): 5644-57, 2010 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-20714318

RESUMO

N,N-dioctyl-azepanium, -piperidinium and -pyrrolidinium bromides 1-3, have been obtained and characterized by FTIR and NMR spectroscopy. DFT calculations have also been carried out. The optimized bond lengths, bond angles and torsion angles calculated by B3LYP/6-31G(d,p) approach have been presented. Both FTIR and Raman spectra of 1-3 are consistent with the calculated structures in the gas phase. The screening constants for 13C and 1H atoms have been calculated by the GIAO/B3LYP/6-31G(d,p) approach and analyzed. Linear correlations between the experimental 1H and 13C chemical shifts and the computed screening constants confirm the optimized geometry.


Assuntos
Brometos/química , Modelos Químicos , Compostos de Amônio Quaternário/química , Brometos/síntese química , Ciclização , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Compostos de Amônio Quaternário/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
20.
Molecules ; 13(2): 379-90, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18305425

RESUMO

1,1-Dimethyl-3-oxo-1,4-diazepan-1-ium chloride (1) and 1,1-dimethyl-1-carboxymethyl-3-aminopropyl ammonium hydrochloride (2) have been obtained by the reactions of 1,1-dimethyl-1,3-propylenediamine with ethyl chloroacetate and chloroacetic acid, respectively. The products have been characterized by FTIR, Raman and NMR spectroscopy. B3LYP calculations have also been carried out. The screening constants for (13)C- and (1)H- atoms have been calculated by the GIAO/B3LYP/6-31G(d,p) approach and analyzed. The FTIR and NMR spectra of the investigated compounds 1 and 2 are in excellent agreement with the structures optimized by Density Functional Theory (DFT) calculations.


Assuntos
Diaminas/química , Diaminas/síntese química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/síntese química , Isótopos de Carbono , Óxido de Deutério/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Prótons , Espectroscopia de Infravermelho com Transformada de Fourier
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