Página 1 dos resultados de 626 itens digitais encontrados em 0.007 segundos

New sustainable processes catalyzed by acids with interest in pharmaceutical chemistry

Mesquita, Lígia Margarida Marques
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Dissertação de Mestrado
ENG
Relevância na Pesquisa
372.62203%
O principal objectivo deste trabalho foi avaliar o poder catalítico de Starbon®400-SO3H na Reacção de Ritter em moléculas esteróides. A crescente importância da Química Verde e a aplicação dos seus princípios na produção e desenvolvimento de novos processos químicos mais eficientes, sustentáveis e ambientalmente aceitáveis têm sido tema de investigação, tanto no meio académico como na indústria farmacêutica. Entre as várias estratégias delineadas na procura de mais eficácia a via que mais se destaca é a Catálise. Neste contexto, Starbon®400-SO3H posiciona-se como um catalisador ambientalmente aceitável por ser completamente orgânico e não tóxico. Os compostos esteróides estão vastamente distribuídos na natureza e que são utilizados como substratos funcionalizáveis na síntese de muitas moléculas biologicamente activas, pelo que centenas de esteróides têm sido isolados a partir de fontes naturais e vários milhares foram obtidos sinteticamente, mantendo-se nos nossos dias, uma intensa investigação com o fim de isolar e identificar novos compostos esteróides com novas actividades biológicas. Tendo em conta as considerações anteriores, foi estudada a actividade catalítica do Starbon®400-SO3H em transformações envolvendo epóxidos esteróides como substratos...

Analytical chemistry in Brazil: healthy and growing

ROCHA, Fábio R. P.; PEREIRA-FILHO, Edenir R.; NÓBREGA, Joaquim A.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
373.30992%
Chemical sciences in Brazil are growing fast and being one of the main supports for the continuous development of the country. Inspired on the 15th Brazilian Meeting on Analytical Chemistry, ENQA, with a record number of participants and communications, we have decided to review recent developments in analytical chemistry in Brazil. We have chosen the same application areas used for the thematic organization of the ENQA and have searched papers published by Brazilian authors in 7 major and general journals in analytical chemistry. The two scientific journals published by the Brazilian Chemical Society were also searched. This review is not comprehensive, but the selected papers published after 2008 shown an impressive overview of the area. We may conclude that analytical chemistry is healthy and growing in Brazilian scenario and certainly will attend the demands of Brazil as an emerged power.; A química brasileira está crescendo rapidamente, sendo um dos principais alicerces para o contínuo desenvolvimento do país. Inspirados no 15º Encontro Nacional de Química Analítica, ENQA, com um número recorde de participantes e comunicações, decidiu-se revisar os recentes desenvolvimentos em química analítica no Brasil. Foram escolhidas as mesmas áreas de aplicação adotadas para a organização temática do ENQA e selecionados artigos publicados por autores brasileiros em 7 periódicos de ampla penetração na área. Os dois periódicos científicos editados pela Sociedade Brasileira de Química também foram pesquisados. Esta revisão não é exaustiva...

Flow injection analysis of paracetamol using a biomimetic sensor as a sensitive and selective amperometric detector

OLIVEIRA, Mariana C. Q.; LANZA, Marcos R. V.; TANAKA, Auro A.; SOTOMAYOR, Maria D. P. T.
Fonte: ROYAL SOC CHEMISTRY Publicador: ROYAL SOC CHEMISTRY
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
372.62203%
This work describes the coupling of a biomimetic sensor to a flow injection system for the sensitive determination of paracetamol. The sensor was prepared as previously described in the literature (M. D. P. T. Sotomayor, A. Sigoli, M. R. V. Lanza, A. A. Tanaka and L. T. Kubota, J. Braz. Chem. Soc., 2008, 19, 734) by modifying a glassy carbon electrode surface with a Nafion (R) membrane doped with iron tetrapyridinoporphyrazine (FeTPyPz), a biomimetic catalyst of the P450 enzyme. The performance of the sensor for paracetamol detection was investigated and optimized in a flow injection system (FIA) using a wall jet electrochemical cell. Under optimized conditions a wide linear response range (1.0 x 10(-5) to 5.0 x 10(-2) mol L(-1)) was obtained, with a sensitivity of 2579 (+/- 129) mu A L mu mol(-1). The detection and quantification limits of the sensor for paracetamol in the FIA system were 1.0 and 3.5 mu mol L(-1), respectively. The analytical frequency was 51 samples h(-1), and over a period of five days (320 determinations) the biosensor maintained practically the same response. The system was successfully applied to paracetamol quantification in seven pharmaceutical formulations and in water samples from six rivers in Sao Paulo State...

Thermal analysis and compatibility studies of prednicarbate with excipients used in semi solid pharmaceutical form

SALVIO NETO, H.; NOVAK, Cs.; MATOS, J. R.
Fonte: SPRINGER Publicador: SPRINGER
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
372.62203%
Differential Scanning Calorimetry (DSC), thermogravimetry/derivative thermogravimetry (TG/DTG) and infrared spectroscopy (IR) techniques were used to investigate the compatibility between prednicarbate and several excipients commonly used in semi solid pharmaceutical form. The thermoanalytical studies of 1:1 (m/m) drug/excipient physical mixtures showed that the beginning of the first thermal decomposition stage of the prednicarbate (T (onset) value) was decreased in the presence of stearyl alcohol and glyceryl stearate compared to the drug alone. For the binary mixture of drug/sodium pirrolidone carboxilate the first thermal decomposition stage was not changed, however the DTG peak temperature (T (peak DTG)) decreased. The comparison of the IR spectra of the drug, the physical mixtures and of the thermally treated samples confirmed the thermal decomposition of prednicarbate. By the comparison of the thermal profiles of 1:1 prednicarbate:excipients mixtures (methylparaben, propylparaben, carbomer 940, acrylate crosspolymer, lactic acid, light liquid paraffin, isopropyl palmitate, myristyl lactate and cetyl alcohol) no interaction was observed.

Determination of ciclopirox olamine in pharmaceutical products by capillary electrophoresis with capacitively coupled contactless conductivity detection

FELIX, Fabiana Silva; LAGO, Claudimir Lucio do; ANGNES, Lucio
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
372.35527%
This paper describes the determination of ciclopirox olamine in pharmaceutical formulations using capillary electrophoresis with capacitively coupled contactless conductivity detection. In an alkaline medium, ciclopirox olamine is converted into an anionic species and its detection is possible in capillary electrophoresis with capacitively coupled contactless conductivity detection without an electroosmotic flow modifier, because it is a low-mobility species. A linear working range from 2.64 to 264 mu g/mL in sodium hydroxide electrolyte as well as low detection limit (0.39 mu g/mL) and a good repeatability (RSD = 3.4% for 264 mu g/mL ciclopirox solution (n = 10)) were achieved. It was also possible to determine olamine in its cationic form when acetic acid was used as the electrolyte solution. The results obtained include a linear range from 26.4 to 184.8 mu g/mL and a detection limit of 2.6 mu g/mL olamine. The proposed methods were applied to the analysis of commercial pharmaceutical products and the results were compared with the values indicated by the manufacturer as well as those obtained using a titrimetric method recommended by American Pharmacopoeia.; FAPESP; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); CNPq; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); CAPES; IM2C (Instituto do Milenio de Materiais Complexos); IM2C (Instituto do Milenio de Materiais Complexos); RENAMI project; RENAMI project; SAMUTI project; SAMUTI project

A simple and precise conductometric method for the determination of losartan in pharmaceutical products

Rossini, Pamela de Oliveira; Felix, Fabiana S.; Angnes, Lucio
Fonte: VERSITA; WARSAW Publicador: VERSITA; WARSAW
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
372.35527%
Losartan is an antihypertensive agent that lost its patent protection in 2010, and, consequently, it has been available in generic form. The latter motivated the search for a rapid and precise alternative method. Here, a simple conductometric titration in aqueous medium is described for the losartan analysis in pharmaceutical formulations. The first step of the titration occurs with the protonation of losartan producing a white precipitate and resulting in a slow increase in conductivity. When the protonation stage is complete, a sharp increase in conductivity occurs which was determined to be due to the presence of excess of acid. The titrimetric method was applied to the determination of losartan in pharmaceutical products and the results are comparable with values obtained using a chromatographic method recommended by the United States Pharmacopoeia. The relative standard deviation for successive measurements of a 125 mg L-1 (2.71x10(-4) mol L-1) losartan solution was approximately 2%. Recovery study in tablet samples ranged between 99 and 102.4%. The procedure is fast, simple, and represents an attractive alternative for losartan quantification in routine analysis. In addition, it avoids organic solvents, minimizes the risk of exposure to the operator...

Inovação e externalização: uma análise de capabilities na indústria farmacêutica.; Innovation and outsourcing: a capability view of pharmaceutical industry.

Andrade, Carolina Almeida Araujo de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 30/04/2010 PT
Relevância na Pesquisa
372.35527%
Esta tese de doutorado trata de como processos inovativos podem ser viabilizados e estimulados a partir da externalização de capabilities antes realizadas internamente à empresa. Para atingir o objetivo proposto foi escolhido o setor farmacêutico, cujo processo inovativo é constante e permeia, em diferentes graus, todas as etapas da cadeia, além da organização da sua cadeia ser propícia à desverticalização. A unidade de análise utilizada é a capability, neste caso as atividades relacionadas a pesquisa e desenvolvimento e manufatura. A partir da consulta de uma base de dados estrangeira, foi selecionado um conjunto de artigos técnicos que incluiu o tema e o setor alvo da tese. A sistematização dos dados permitiu identificar o tipo de atividade externalizada, a situação em que isso ocorria, suas principais motivações e resultados, bem como os detalhes das empresas envolvidas. A análise da externalização de atividades de pesquisa mostra quatro formas de aceleração da inovação: (1) aquela alcançada a partir do acesso a tecnologias que não seriam acessíveis de outra maneira, acelerando a fase clínica do desenvolvimento; (2) a que agrega etapas permitindo acelerar a fase clínica do desenvolvimento; (3) a da etapa de formulação que possibilitou acelerar o estágio de desenvolvimento...

Funcionalização do 3,4,6-tri-O-acetil-D-glucal com sais de organotrifluoroboratos de potássio e reações de click chemistry para a geração e funcionalização de triazóis; Functionalization of 3,4,6-tri-O-acetyl-D-glucal with potassium organotrifluoroborate salts and click chemistry reactions for the generation and functionalization of triazoles.

Silva, Nathalia Cristina da Silva e
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 22/02/2013 PT
Relevância na Pesquisa
373.30992%
No presente trabalho, foi desenvolvida uma metodologia sintética para a funcionalização de um monossacarídeo derivado da D-glicose através do Rearranjo de Ferrier, utilizando-se um sal de organotrifluoroborato de potássio como nucleófilo. Em seguida, foi feita a reação de cicloadição azida-acetileno com cobre, através de estratégias simples e eficientes, que seguem a filosofia da click chemistry, permitindo a preparação de uma série de compostos com grande diversidade estrutural, possuindo dois anéis heterocíclicos e diversos substituintes, com promissora atividade biológica. Dando continuidade ao projeto, foi feita a metanólise dos grupamentos acetila, com carbonato de potássio e metanol. Assim, as novas moléculas adquirem maior hidrofilicidade e podem ser enviadas para novos testes biológicos, para fins de comparação com as anteriores. A partir dos compostos desprotegidos, foi feita a mesilação seletiva da hidroxila primária do açúcar e a substituição com selenolato de sódio, com a obtenção de seleno-carboidratos inéditos. Em uma segunda etapa do trabalho, exploramos a reatividade do núcleo triazólico, com a reação de troca Te/Li seguida de captura por eletrófilo. O material de partida foi sintetizado a partir do fenil acetileno. Com o triazol telurado em mãos...

A simple and environmentally friendly reflectometric method for the rapid quantitative analysis of captopril in pharmaceutical formulations

Ribeiro, Paulo Roberto S.; Pezza, Leonardo; Pezza, Helena R.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 91-103
ENG
Relevância na Pesquisa
372.35527%
This paper describes a simple, environmentally friendly and rapid quantitative spot test procedure for the determination of captopril (CPT) in bulk drug and in pharmaceutical formulations by using diffuse reflectance spectroscopy. The proposed method is based on the reflectance measurements of the orange compound (λ max 490 nm) produced by the spot test reaction between CPT and p-chloranil (CL). Under optimal conditions, calibration curves were obtained for CPT by plotting the optical density of the reflectance signal (A R) vs. the log of the mol L -1 concentration, from 6.91×10 -3 to 1.17×10 -1, with a good coefficient of determination (R 2 = 0.9992). The common excipients used as additives in pharmaceuticals do not interfere in the proposed method. The method was applied to determine CPT in commercial pharmaceutical formulations. The results obtained by the proposed method are compared favorably with those obtained by an official procedure at 95% confidence level. The method validation results showed that the sensitivity and selectivity of the methods were adequated for drug monitoring in industrial quality control laboratories. © 2011 Moment Publication.

Evaluation of the antioxidant and anti-inflammatory activities of synthetic 2-styrylchromones

Gomes, Ana Maria de Carvalhais Mendes
Fonte: Faculdade de Farmácia da Universidade do Porto; FFUP Publicador: Faculdade de Farmácia da Universidade do Porto; FFUP
Tipo: Tese de Doutorado Formato: application/pdf
POR
Relevância na Pesquisa
472.62203%
Doutoramento em Química Farmacêutica; PhD Degree - Pharmaceutical Chemistry

Study on solubility of pharmaceutical compounds in ionic liquids

Santos, Ana Rute Duarte dos
Fonte: Faculdade de Ciências e Tecnologia Publicador: Faculdade de Ciências e Tecnologia
Tipo: Dissertação de Mestrado
Publicado em //2013 ENG
Relevância na Pesquisa
372.35527%
Dissertation to obtain the degree of master in Chemical and Biochemical Engineering; The sufficient solubility of N-acetyl-L-cysteine (NAC), coumarin (COU) and 4-hydroxycoumarin (4HC) in alternative solvents obtained in this work can open new perspectives in pharmaceutical processing. Solid–liquid equilibrium (SLE) measurements have been made using a dynamic (synthetic) method. The melting point and the enthalpy of fusion of the pharmaceutical compounds were acquired using differential scanning calorimetry (DSC). The solubility of N-acetyl-L-cysteine and 4-hydroxycoumarin in trifluoromethanesulfonate ionic liquids was found to be significantly higher than in the studied bis(trifluoromethylsulfonyl)imide ionic liquids, and when compared, coumarin have the opposite behaviour. The best solvent amongst studied for this antioxidant (NAC) and anticoagulants (COU and 4HC) was discovered. The solid–liquid phase equilibrium were described using six different correlation equations which revealed relatively good description with the acceptable standard deviation temperature range. Moreover, the solubility data was used to calculate the 1-octanol/water partition coefficients and experimental partition coefficients (logP) was found to be negative in N-acetyl-L-cysteine and positive in the case of coumarin...

Analytical chemistry in Brazil: healthy and growing

Rocha,Fábio R. P.; Pereira-Filho,Edenir R.; Nóbrega,Joaquim A.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2009 EN
Relevância na Pesquisa
373.30992%
Chemical sciences in Brazil are growing fast and being one of the main supports for the continuous development of the country. Inspired on the 15th Brazilian Meeting on Analytical Chemistry, ENQA, with a record number of participants and communications, we have decided to review recent developments in analytical chemistry in Brazil. We have chosen the same application areas used for the thematic organization of the ENQA and have searched papers published by Brazilian authors in 7 major and general journals in analytical chemistry. The two scientific journals published by the Brazilian Chemical Society were also searched. This review is not comprehensive, but the selected papers published after 2008 shown an impressive overview of the area. We may conclude that analytical chemistry is healthy and growing in Brazilian scenario and certainly will attend the demands of Brazil as an emerged power.

Instructional Model to Teach Clinically Relevant Medicinal Chemistry

Alsharif, Naser Z.; Galt, Kimberly A.; Mehanna, Ahmed; Chapman, Robert; Ogunbadeniyi, Alaba M.
Fonte: American Journal of Pharmaceutical Education Publicador: American Journal of Pharmaceutical Education
Tipo: Artigo de Revista Científica
Publicado em 15/08/2006 EN
Relevância na Pesquisa
382.43926%
The relevance of medicinal chemistry to pharmacy practice has been questioned by many pharmacy educators as more emphasis has been placed on linking clinical knowledge and practice to pharmacy student educational outcomes. Faculty teaching in medicinal chemistry and other biomedical and pharmaceutical science courses have embraced this challenge. Various teaching methods and approaches within medicinal chemistry that emphasize application of this knowledge have been sought to improve the usefulness of this scientific discipline to the future careers of students. The newly revised ACPE guidelines and standards have reemphasized the role of the sciences in the curriculum. With this mandate, it is essential that all science faculty members adjust the way they teach to meet the new desired outcomes for pharmacy graduates. This manuscript describes an instructional model for teaching medicinal chemistry explicitly designed to meet these outcomes. A process of collaboration between experienced pharmacy faculty scholars was used to derive this approach. Pedagogy for cognitive and affective learning was incorporated. A case study using a representative drug class is presented to illustrate this model.

Recent Trends on the Future of Graduate Education in the Pharmaceutical Sciences and Research

Kushwaha, KSS; Kushwaha, N; Rai, AK
Fonte: Medknow Publications Publicador: Medknow Publications
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
Relevância na Pesquisa
372.35527%
Harmonization of pharmacy education has to be made a global agenda that will encompass the developments that have taken place in basic, medical, pharmaceutical sciences in serving the needs and expectations of the society. The professional pharmacy curriculum is designed to produce pharmacists who have the abilities and skills to provide drug information, education, and pharmaceutical care to patients; manage the pharmacy and its medication distribution and control systems; and promote public health. Required coursework for all pharmacy students includes pharmaceutical chemistry; pharmaceutics (drug dosage forms, delivery, and disposition in the human body) pharmacology; therapeutics (the clinical use of drugs and dietary supplements in patients); drug information and analysis; pharmacy administration (including pharmacy law, bioethics, health systems, pharmacoeconomics, medical informatics); clinical skills (physical assessment, patient counseling, drug therapy monitoring for appropriate selection, dose, effect, interactions, use); and clinical pharmacy practice in pharmacies, industry, health maintenance organizations, hospital wards, and ambulatory care clinics.

Medicinal Chemistry and the Pharmacy Curriculum

Faruk Khan, M.O.; Deimling, Michael J.; Philip, Ashok
Fonte: American Journal of Pharmaceutical Education Publicador: American Journal of Pharmaceutical Education
Tipo: Artigo de Revista Científica
Publicado em 10/10/2011 EN
Relevância na Pesquisa
373.30992%
The origins and advancements of pharmacy, medicinal chemistry, and drug discovery are interwoven in nature. Medicinal chemistry provides pharmacy students with a thorough understanding of drug mechanisms of action, structure-activity relationships (SAR), acid-base and physicochemical properties, and absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiles. A comprehensive understanding of the chemical basis of drug action equips pharmacy students with the ability to answer rationally the “why” and “how” questions related to drug action and it sets the pharmacist apart as the chemical expert among health care professionals. By imparting an exclusive knowledge base, medicinal chemistry plays a vital role in providing critical thinking and evidence-based problem-solving skills to pharmacy students, enabling them to make optimal patient-specific therapeutic decisions. This review highlights the parallel nature of the history of pharmacy and medicinal chemistry, as well as the key elements of medicinal chemistry and drug discovery that make it an indispensable component of the pharmacy curriculum.

Pharmaceutical study of Lauha Bhasma

Singh, Neetu; Reddy, K. R. C.
Fonte: Medknow Publications Pvt Ltd Publicador: Medknow Publications Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em //2010 EN
Relevância na Pesquisa
474.66637%
In the present research paper, the work done on pharmaceutical study of Lauha Bhasma conducted in the Department of Rasa Shastra under the postgraduate research programme is being presented. The pharmaceutical processing of Lauha Bhasma was performed by following samanya shodhana, vishesha shodhana and marana of Lauha. Under the process of marana, three specific pharmaceutical techniques were followed, viz. bhanupaka, sthalipaka and putapaka. During the putapaka process, an electric muffle furnace (EMF) was used. The temperature of puta was studied in two batches, viz. in Batch I, a temperature of 800°C was maintained whereas in Batch II, a temperature of 600°C was maintained. The purpose behind selecting two temperatures was to validate the process of marana of Lauha and to determine an ideal temperature for the preparation of Lauha Bhasma in EMF. It is found that after 20 puta at a temperature of 600°C, the Lauha Bhasma was prepared properly. The entire characteristic of Lauha Bhasma, like “pakwa jambu phala varna,” varitar, etc. was attained at 600°. At a temperature of 800°C, the process could not be carried out smoothly. The pellets turned very hard and brassy yellow in color. The desired color was attained only after decreasing the temperature in further puta.

Total synthesis of (-)-safracin B total synthesis of (-)-thiangazole development of sulfonamide chemistry

Cheung, Mui
Fonte: Universidade Rice Publicador: Universidade Rice
ENG
Relevância na Pesquisa
469.8417%
Chapter I describes the stereocontrolled total synthesis of ($-$)-safracin B with antibacterial and antitumor activities. The convergent approach for the synthesis of safracin B can be readily applied to the synthesis of the related isoquinolinequinone family such as saframycins and ecteinascidins. Chapter II discusses the total synthesis of ($-$)-thiangazole, a substance with potent anti-HIV-1 activity in vitro. An efficient synthetic pathway is developed to enable diverse modification of both ends of thiangazole and thus provide a rapid access to a variety of analogs. Chapter III outlines the development of new chemistry of nitrobenzenesulfonamides, N-Boc and N-Alloc nitrobenzene sulfonamides, and alkylsulfonamides for the efficient preparation of secondary amines and protected primary amines.

Strain Promoted Click Chemistry of 8-Azidopurine and 5-Azidopyrimidine Nucleosides and Nucleotides with Cyclooctynes and Applications to Living Cell Imaging

Zayas, Jessica
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Relevância na Pesquisa
471.8555%
The strain promoted azide alkyne cycloaddition (SPAAC) of azido nucleobase modified nucleosides and nucleotides with cyclooctynes to give fluorescent triazoles has been relatively unexplored. Thus, SPAAC between azido-nucleobases and various cyclooctynes in aqueous solution at ambient temperature resulted in the efficient formation (3 min - 2 h) of triazole products with inherent fluorescent properties. The 2- and 8-azidoadenine nucleosides reacted with fused cyclopropyl cyclooctyne, dibenzylcyclooctyne or monofluorocyclooctyne to produce click products functionalized with hydroxyl, amino, N-hydroxysuccinimide, or biotin moieties. The previously unexplored 5-azidouridine and labile 5-azido-2'-deoxyuridine were similarly converted to the analogous triazole products in quantitative yields in less than 5 minutes. The 8-azido-ATP quantitatively afforded the triazole product with fused cyclopropyl cyclooctyne (3 h). Addition of a triazole ring at the 2 or 8 position of adenine or 5-position of uracil induces fluorescent properties which were used for direct imaging with fluorescent microscopy in MCF-7 cancer cells without the need for traditional fluorogenic reporters. Fluorescent lifetime imaging microscopy of the click adducts in live cells were used to determine the lifetime of each fluorophore in the cellular nuclei demonstrating the potential utility of the synthesized triazole adducts for dynamic measuring and tracking of events inside single living cancer cells. The SPAAC methodology developed has also been applied to study the cellular targets in protozoal parasite...

The study of organic crystals by atomic force microscopy

Chow, Ernest Ho Hin
Fonte: University of Cambridge; Department of Chemistry Publicador: University of Cambridge; Department of Chemistry
Tipo: Thesis; doctoral; PhD
EN
Relevância na Pesquisa
380.42547%
Organic crystals are found in everyday goods such as foods, drugs, dyes, and agricultural products. To better understand the solid-state behaviour of organic crystals, the study of their surfaces is crucial, as several reactions occur at the interface between the crystal surface and its immediate environment. While atomic force microscopy (AFM) is a useful tool for studying surfaces, it is not a common technique for studying organic crystals. The rst part of this report aims to address problems of imaging organic crystals by AFM which arise from the nature of the imaging technique and the material property of organic crystals. Methods of detecting and predicting the likelihood of the problems encountered in imaging organic crystals are suggested in order for a more accurate interpretation of the information obtained by this technique. The e ect of humidity on aspirin crystal surfaces is then investigated by AFM. The growth of new features on the surface is believed to be a result of the hydrolysis of aspirin molecules. Mechanisms are suggested based on the observed surface response of aspirin, where surface defects and the mobility of surface molecules are believed to be important factors a ecting reactivity. The last section investigates the solid-state photochemical reaction of anthracene...

Solution-phase combinatorial synthesis; Peptide derivatives of ethyl p-aminobenzoate

Scuderi, Andrea
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
372.62203%
The need to find more efficient and cost-effective methods of drug development has led pharmaceutical companies to examine combinatorial means of synthesis. The ability to carry out parallel synthesis by the hundreds of compounds is rapidly advancing synthetic, analytical, and biological research. In this thesis project, peptide derivatives of ethyl paminobenzoate were synthesized via solution phase combinatorial techniques. A total of 27 tri-peptide analogs were produced, using a polymer-supported carbodiimide resin as the coupling agent. The structures of all products and intermediates were confirmed by LC-MS. Two methods were used for sequential deprotection of these analogs. The traditional method using the mild base, piperidine, was used as well as a polymersupported thiophenol method. Upon comparison of both methods, we concluded that the piperidine deprotection afforded a higher yield of the desired unprotected peptide.