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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Síntese e avaliação biológica de derivados de goniotalamina / Synthesis and biological evaluation of derivatives goniotalamina

Pereira, Vanessa Caixeta 08 December 2011 (has links)
Orientador: Ronaldo Aloise Pilli / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-19T04:40:46Z (GMT). No. of bitstreams: 1 Pereira_VanessaCaixeta_M.pdf: 3243379 bytes, checksum: e0935d08b333881437e8413863fa0ff7 (MD5) Previous issue date: 2011 / Resumo: A goniotalamina (9), produto natural isolado de diversas plantas do gênero Goniothalamus, vem se destacando por sua potência em teste de triagem in vitro contra linhagens de células tumorais, bem como pelos resultados positivos em modelos tumorais in vivo. Isso faz com que a goniotalamina sirva como modelo para a síntese e avaliação de novos compostos. Com base nisso, propomos sintetizar e avaliar a atividade citotóxica de duas classes de derivados de 9. A primeira classe são os derivados com substituintes oxigenados na posição 4 da 5,6-di-hidropiran-2-ona. Os derivados alquil e acil (17,24-28) foram obtidos a partir da kavalactona (23) através de reações clássicas de alquilação e acilação em rendimentos que variaram de baixo a excelente. Por sua vez, a kavalactona (23) foi obtida através de uma reação de aldol seguida de lactonização in situ entre o cinamaldeído (10) e acetoacetato de etila (29) em 15% de rendimento. O ensaio de atividade antiproliferativa in vitro mostrou que nenhum dos derivados avaliados foi mais citotóxico que a goniotalamina (9) e que nenhum dos compostos apresentou seletividade para as linhagens avaliadas. Outra classe de compostos avaliada foram os derivados nitrogenados da goniotalamina (9) que apresentam a substituição do anel lactônico por um anel lactâmico. Os derivados lactâmicos 46 a 51 foram sintetizados em 3 etapas e rendimentos globais que variaram de 18 a 60%. A primeira etapa consistiu na formação da imina a partir do respectivo aldeído (10,52-56) seguida de alilação com brometo de alilmagnésio para a formação da amina primária 57. Esta foi convertida em uma amida 58 através da reação com cloreto de acriloíla ou crotonoíla. E por fim, a lactama foi obtida após o tratamento da amida 58 com 6 mol% do catalisador de Grubbs de segunda geração. A avaliação da atividade antiproliferativa in vitro desses derivados mostrou que nenhum deles apresentou citotoxicidade maior que 9. Entretanto, o derivado 49 apresentou seletividade para duas linhagens de células tumorais PC-03 (próstata) e K562 (leucemia) / Abstract: Goniothalamin (9), a natural product isolated from several plants of the Goniothalamus genus, has been highlighted in the literature for presenting good potency against human tumor cell lines in in vitro assays, as well as good results in in vivo models. This makes goniothalamin a promising model for designing new compounds. Herein, we propose the synthesis and the cytotoxic evaluation of two classes of goniothalamin derivatives. The first class comprises derivatives with substituents at position 4 of the 5,6-di-hydropyran-2-one moiety. Alkyl and acyl derivatives (17,24-28) were obtained from kavalactone (23) after well-known alkylation and acylation reaction in bad to good yields. Kavalactone (23) was obtained from cinnamaldehyde (10) and ethyl acetoacetate (29) via an aldol reaction followed by in situ lactonization, in 15% yield. The antiproliferative assay showed that none of these derivatives was more cytotoxic than goniothalamin and none presented selectivity for tumor cell lines. The second class of compounds presents the substitution of the lactone by a lactam moiety. Lactam derivatives 46 - 51 were synthesized in 3 steps and overall yields ranging from 18 to 60%. The first step was the imine formation from the respective aldehyde (10,52-56) followed by allylmagnesium bromide addition to form primary amine 57. This was reacted with acryloyl or crotonoyl chloride to generate amide 58. Finally, the desired lactam was obtained by treating amide 58 with 6 mol% of Grubbs¿ second generation catalyst. The in vitro antiproliferative evaluation showed that 9 was more cytotoxic than the derivatives. However, derivative 49 presented selectivity for two tumor cell lines PC-03 (prostate) and K562 (leukemia) / Mestrado / Quimica Organica / Mestre em Química
12

Prospecção de antioxidantes e de substâncias com atividade antiproliferativa em campomanesia adamantium (Myrtaceae) / Prospect of antioxidants and antiproliferative substances in campomanesia adamantium (Myrtaceae) : Aislan Cristina Rheder Fagundes Pascoal

Pascoal, Aislan Cristina Rheder Fagundes, 1982- 20 August 2018 (has links)
Orientador: Marcos José Salvador / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T10:39:23Z (GMT). No. of bitstreams: 1 Pascoal_AislanCristinaRhederFagundes_M.pdf: 4510440 bytes, checksum: 168a21e640dc3b31d66e0351b69fee87 (MD5) Previous issue date: 2012 / Resumo: Campomanesia adamantium (Cambess.) O. Berg (Myrtaceae) é uma planta popularmente conhecida como gabiroba ou guaviroba, cujos frutos são comestíveis. Suas folhas e cascas são usadas na medicina popular como antiinflamatórias, antidiarréicas, anti-sépticas das vias urinárias e para o tratamento da gripe. Como parte de um programa de bioprospecção que visa à descoberta de produtos naturais bioativos, o presente estudo teve por objetivo a prospecção de metabólitos secundários com atividade antioxidante e antiproliferativa acumulados no extrato etanólico das folhas de C. adamantium. Para tanto, adequou-se a metodologia para a avaliação in vitro da atividade antioxidante (redução do radical DPPH e ORACFL) e antiproliferativa, frente a linhagens de células tumorais humanas e procedeu-se o estudo fitoquímico, buscando-se a identificação dos constituintes majoritários ativos. Inicialmente obteve-se o perfil dos extratos ativos (HPLC-DAD e ESI-MS), identificando algumas substâncias conhecidas diretamente no extrato bruto e frações (desreplicação). Os extratos ativos foram submetidos ao fracionamento guiado pela atividade antioxidante e antiproliferativa e para a substância isolada e purificada realizou-se a elucidação estrutural utilizando-se métodos espectroscópicos de análise (RMN (1D e 2D ) e espectrometria de massas). Ainda, buscou-se avaliar se a substância purificada induz a morte celular por apoptose frente à linhagem de célula de câncer de próstata (PC-3) com análise de expressão do RNAm por PCR semiquantitativo do genes BAX e BCl-2 e a fragmentação do DNA por citometria de fluxo. Com base nos resultados sugere-se que: (1) o extrato bruto etanólico das folhas de C. adamantium e suas frações butanólica e acetato de etila apresentaram atividade antiproliferativa frente a linhagens tumorais humanas; (2) o extrato bruto etanólico das folhas de C. adamantium e suas frações butanólica e acetato de etila apresentaram atividade antioxidante tanto pelo método indireto DPPH (baseado em mecanismos de transferência de elétrons), quanto pelo ensaio ORACFL (método direto, cinético, baseado em mecanismos de transferência de hidrogênio). A atividade antioxidante destas amostras pode ser relacionada com o alto teor de substâncias fenólicas totais solúveis estimado pelo método colorimétrico Folin Ciocalteu; (3) análises empregando HPLC-DAD e ESI-MS e MS-MS dos extratos e frações com atividade antioxidante sugeriram a presença dos flavonóides isoquercitrina (Ca1), quercitrina (Ca2), miricetina (Ca3), quercetina (Ca4) e das chalconas 2',4'-diidroxi-6'-metoxichalcona (Ca5), 2',4'-diidroxi-5'-metil-6'-metoxichalcona (Ca6) e 2',4'-diidroxi-3',5'-dimetil-6'-metoxichalcona (Ca7); (4) o estudo fitoquímico da fração acetato de etila levou ao isolamento e identificação da chalcona Ca5, que apresentou promissora atividade antiproliferativa frente a algumas das linhagens de células tumorais humanas estudadas; (5) as análises de expressão dos genes BAX e BCl-2 não apresentaram alterações significativas em relação às células controles que indicassem indução de apoptose. Porém, com a análise por citometria de fluxo da fragmentação do DNA pode-se observar que as células que foram tratadas com a chalcona isolada (Ca5) tiveram um aumento significativo da fragmentação, indicando indução do processo apoptótico. Assim, procedeu-se o estudo com C. adamantium para a busca de compostos com atividade antioxidante e antiproliferativa de origem vegetal, o que pode vir a contribuir para a quimioprevenção de doenças relacionadas com o estresse oxidativo (doenças degenerativas, câncer, cardiovasculares, inflamatórias) e para obter novas fontes de insumos farmacêuticos / Abstract: Campomanesia adamantium (Cambess.) O. Berg (Myrtaceae) is a plant popularly known as gabiroba or guaviroba, whose fruits are edible. Its leaves and bark are used in folk medicine as anti-inflammatory, antidiarrheal, antiseptic of the urinary tract and treatment of flu. As part of a bioprospecting program aimed at the discovery of bioactive natural products, this study aims at prospecting with phyto-derived antioxidant and antiproliferative activity accumulated in the ethanol extract from leaves of C. adamantium. To this end, it has adapted methods for in vitro evaluation of antioxidant activity (DPPH radical reduction and ORACFL assays) and antiproliferative activity against human tumor cell lines and proceeded to the phytochemical study, seeking to identify the major constituents active. Initially, we obtained the profile of the active extracts (HPLC-DAD and ESI-MS), identifying some known substances directly into the crude extract and fractions (dereplication). The active extracts were subjected to fractionation guided by the antioxidant and antiproliferative activities and the compound isolated and purified held structural elucidation using spectroscopic analysis (NMR (1D and 2D) and mass spectrometry). Still, we sought to assess whether the purified substance induces cell death by apoptosis front of the cell line of prostate cancer (PC-3) with analysis of mRNA expression by semiquantitative PCR of the genes BAX and BCL-2 and DNA fragmentation by flow cytometry. The results suggest that: (1) the crude ethanol extract of leaves of C. adamantium and its fractions in butanol and ethyl acetate showed antiproliferative activity against human tumor lines; (2) the crude ethanol extract of leaves of C. adamantium and its fractions butanol and ethyl acetate showed antioxidant activity proved both by DPPH method (based on mechanisms of electron transfer), and by the ORACFL assay (kinetic method based on mechanisms of hydrogen transfer). The antioxidant activity of these samples may be related to the high content of total soluble phenolic substances estimated by the Folin Ciocalteu colorimetric assay; (3) analysis employing HPLC-DAD, ESI-MS and MS-MS of extracts and fractions with antioxidant activity suggested the presence of flavonoids isoquercitrin (Ca1), quercitrin (Ca2), myricetin (Ca3), quercetin (Ca4) chalcones and 2 ', 4'-dihydroxy- 6'-metoxichalcona (Ca5), 2', 4'-dihydroxy-5'-methyl-6 '-metoxichalcona (Ca6) and 2', 4'-dihydroxy-3 ', 5'-dimethyl-6'-metoxichalcona (Ca7); (4) the phytochemical study of ethyl acetate fraction led to the isolation and identification of the chalcone Ca5 which showed promising antiproliferative activity against some human tumor cell lines studied; (5) analysis of gene expression of BAX and BCL-2 showed no changes, but DNA fragmentation can be observed apoptosis in cells that were treated with chalcone Ca5. Thus, we proceeded the study of C. adamantium to search of natural products with antioxidant and antiproliferative activities, to contribute to the chemoprevention of diseases related to oxidative stress (degenerative diseases, cancer, cardiovascular, inflammatory) and to obtain new sources of pharmaceutical products / Mestrado / Biologia Vegetal / Mestre em Biologia Vegetal
13

Caracterização e avaliação das atividades antioxidante e antiproliferativa e do efeito citotóxico de bebidas funcionais liofilizadas compostas por frutas e hortaliças (green smoothies) / Characterization and evaluation of antioxidant and antiproliferative activities and cytotoxicity effect of lyophilized functional beverages composed by fruits and vegetables (green smoothies)

Dantas, Érica Mara, 1986- 26 August 2018 (has links)
Orientador: Gláucia Maria Pastore / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-26T10:07:58Z (GMT). No. of bitstreams: 1 Dantas_EricaMara_D.pdf: 2161426 bytes, checksum: aba5b3802cfe09e4d134b209a2879a7c (MD5) Previous issue date: 2014 / Resumo: Considerando a necessidade de consumo de quantidade significativa de frutas e hortaliças para alcançar a ingestão diária de nutrientes e compostos bioativos, o presente estudo teve como objetivo desenvolver e caracterizar duas bebidas funcionais liofilizadas a base de frutas e hortaliças (Green Smoothies). Na composição centesimal, vitamínica e mineral, a BMFH (1) obteve os maiores valores para a maior parte das determinações, exceto para o teor de fibra alimentar, sódio, vitamina B2, vitamina C e zinco. As duas bebidas destacaram-se pelos baixos valores calóricos e por conterem alto teor de fibra alimentar, por serem fonte de vitamina A, manganês e, além disso, a BMFH (1) por ser fonte de magnésio. Em relação ao equivalente de porções de frutas e vegetais supridos no valor diário recomendado, as BMFHs apresentaram menores quantidades do que de uma porção de banana apenas para os conteúdos de magnésio e de vitaminas B6 e C e iguais em vitamina B2. Obtiveram quantidades equivalentes a 3 porções de frutas e vegetais em relação aos lipídios, fibras, manganês, fósforo e zinco, e a 4 porções em relação a carboidratos, cálcio, ferro, potássio e cobre. Quando comparadas a bebidas comerciais similares, o teor de 6 composições das duas bebidas foram maiores do que a maioria das bebidas comerciais analisadas, e menores em conteúdo 4 determinações. Entre as duas bebidas formuladas, não foram encontradas diferenças significativas para o pH, ºbrix, glicose e pectina; a % acidez titulável, sacarose, flavonoides totais e fibras solúveis foram maiores na BMFH (1); a relação ratio, frutose e fibras insolúveis foram maiores na BMFH (2); para ambas as bebidas, as maiores concentrações de mono- e dissacarídeos se deram para a sacarose, e em ambas foram identificados fruto- e maltooligossacarídeos, sendo que o primeiro foi encontrado em maior quantidade na BMFH (1) e o último em maior concentração na BMFH (2). Na avaliação da cor, não houve diferenças em relação à luminosidade, mas a BMFH (1) apresentou tonalidades mais tendentes ao verde e ao amarelo, pela maior concentração de clorofilas e de ?-caroteno. Antes da digestão in vitro, ambas as amostras apresentaram 6 dos 17 flavonoides testados, mas diferiram com a presença de outras duas na BMFH (1) e de outras 3 na BMFH (2). Foram obtidos maiores resultados de Fenóis Totais para a couve fresca e hortelã liofilizada, no teste de DPPH-trolox pelo extrato aquoso de couve fresca, na análise de TEAC e ORAC o extrato aquoso de hortelã fresca. Entre as bebidas, a amostra digerida de BMFH (1) obteve os maiores resultados de Fenóis Totais, DPPH-trolox e TEAC, e na análise de ORAC, pela amostra digerida de BMFH (2). Sugere-se uma atividade citostática muito fraca, sendo que as BMFHs são praticamente inativas para atividade antiproliferativa. Na análise de CAA, o maior resultado foi encontrado na amostra BMFH (2) antes da digestão. Comprovou-se que o processamento, armazenamento e digestão in vitro afetam a composição de flavonoides dos alimentos e os resultados de fenólicos totais e capacidade antioxidante, através da perda ou produção de alguns compostos, além de demonstrar que a eficiência da extração é dependente das condições do processo e da matriz testada / Abstract: Considering the need for consumption of significant amounts of fruits and vegetables to achieve the daily intake of nutrients and bioactive compounds, this study aimed to develop and characterize two lyophilized fruit and vegetables functional beverages (Green Smoothies). Proximate, vitamin and mineral composition, MFVD (1) obtained higher values for most determinations, except for the dietary fiber, sodium, Vitamin B2, Vitamin C and zinc. Both beverages highlighted by the low calorific values and high value of dietary fiber, and because they are sources of vitamin A and manganese and furthermore MFVD (1) to be a source of magnesium. When evaluated in relation to the equivalent servings of fruits and vegetables supplied in recommended daily value, MFVDs showed only minor amounts for the contents of magnesium and vitamins B6 and C, and equal to vitamin B2. Obtained amount equivalent to 3 portions of fruits and vegetables relative to fiber, lipids, manganese, phosphorus and zinc, and 4 servings compared to carbohydrates, calcium, iron, potassium and copper. When compared to similar commercial beverages, the amount of 6 compositions of the two beverages were higher than most commercial beverages analyzed, and lower in 4 content determinations. Between the two formulated drinks, no significant differences were found for pH, ºbrix, glucose and pectin; the titratable acidity %, sucrose, total flavonoids and soluble fiber were higher in MFVD (1); the ratio relation, fructose and insoluble fiber were higher in MFVD (2); for both drinks, the higher concentrations of mono- and disaccharides are given for sucrose, and both fruit- and maltooligosaccharides were identified, the first of which was found in greater quantities in MFVD (1) and the latest in high concentration in the MFVD (2). In the evaluation of color, there were no differences in relation to brightness, but the MFVD (1) showed more conducive to green and yellow tones, caused by the highest concentration of chlorophyll and ?-carotene. Prior to in vitro digestion, both samples showed 6 of 17 flavonoids tested, but differ in the presence other 2 in MFVD (1) and other 3 in MFVD (2). Higher total phenolic results were obtained for fresh kale and lyophilized mint, in the DPPH-trolox test by aqueous extract of fresh kale, in the analysis of TEAC and ORAC by aqueous extract of fresh mint. Between MFVDs, the digested sample of MFVD (1) obtained the highest results of Total Phenols, DPPH-trolox and TEAC, and in ORAC analysis, by the digested sample of MFVD (2). A very weak cytostatic activity is suggested, while the samples of MFVD are practically inactive for antiproliferative activity, and in CAA analysis the best result was found in the sample MFVD (2) before digestion. It was shown that the processing, storage and in vitro digestion affect the composition of flavonoids from food, total phenolic content and antioxidant capacity, through loss or production of some compounds, and demonstrate that the extraction efficiency is dependent on the process conditions and tested array / Doutorado / Ciência de Alimentos / Doutora em Ciência de Alimentos
14

Sinteza i antiproliferativna aktivnost novih D-homo i D-seko derivata androstana / Synthesis and antiproliferative activity of new D-homo and D-seco androstane derivatives

Savić Marina P. 19 March 2013 (has links)
<p>U prvom delu ove doktorske disertacije je izvr&scaron;ena<br />sinteza novih derivata androstana sa D-laktonskom<br />funkcijom ili D-seko derivata, sa modifikacijama u Ai/<br />ili B-prstenovima. U drugom delu je ispitana<br />antiproliferativna aktivnost odabranih<br />novosintetizovanih jedinjenja prema humanim<br />tumorskim ćelijskim linijama (MCF-7, MDA-MB-231,<br />PC-3, HeLa, HT-29, K562) kao i prema zdravim<br />ćelijama fetalnih fibroblasta pluća (MRC-5).</p> / <p>In first part of this work was achieved synthesis of&nbsp;some new androstane derivatives with D-lactone&nbsp;function and new D-seco derivatives with modification&nbsp;in A and/or B rings. In the second part the&nbsp;antiproliferative activity of selected newly synthesized&nbsp;compounds by human carcinoma cell lines (MCF-7,&nbsp;MDA-MB-231, PC-3, HeLa, HT-29, K562) and the&nbsp;healthy cells of fetal lung fibroblasts (MRC-5 ) was&nbsp;examined.</p>
15

Sinteza i biološka aktivnost 17-supstituisanih androstanskih derivata / Synthesis and biological activity of 17-substituted androstane derivatives

Ajduković Jovana 08 October 2013 (has links)
<p>U prvom delu ove doktorske disertacije je izvr&scaron;ena sinteza&nbsp;novih 17&alpha;-pikolil i 17(E)-pikoliniliden androstanskih&nbsp;derivata, sa modifikacijama u A- i/ili B-prstenovima. U&nbsp;drugom delu rada je ispitana antiproliferativna aktivnost&nbsp;odabranih novosintetizovanih jedinjenja prema humanim&nbsp;tumorskim&nbsp; ćelijskim linijama (MCF-7, MDA-MB-231,&nbsp;PC-3, HeLa, HT-29 i A549) kao i prema zdravim ćelijama&nbsp;fetalnih fibroblasta pluća (MRC-5).</p> / <p>In the first part of this dissertation, the synthesis of new&nbsp;17&alpha;-picolyl and 17(E)-picolinylidene androstane&nbsp;derivatives with modifications in A and/or B rings, were&nbsp;presented. The second part of the work consisted on&nbsp;investigation of antiproliferative activity of selected newly&nbsp;synthesized compounds toward human carcinoma cell lines&nbsp;(MCF-7, MDA-MB-231, PC-3, HeLa, HT-29 and A549),&nbsp;as well as the healthy fetal lung fibroblasts (MRC-5).</p>
16

Antiproliferative Activity of 3,5,7- Trihydroxy -6- Methoxy Flavone Obtained From Chromolaena Leivensis (Hieron) on Cancer Cell Lines of Breast, Prostate, Lung, Colon and Cervix

Torrenegra, R. D., Rodríguez, J., Rodríguez, O. E., Palau, V. E., Méndez, G. M. 30 April 2016 (has links)
The flavone 3,5,7-trihydroxy-6-methoxyflavone was isolated from leaf extracts of Chromolaena leivensis (Hieron), commonly named plant of cancer. It was identified based on their physicochemical propierties and spectroscopic data. This compound presented a methoxylation at C6, this is uncommon in flavonoids and which may confer some specificity of its biological activity. The cytotoxic activity of this flavonoid was determined on PC3 (prostate), MDA- MB-231 (breast), HT29 (colon), SiHa (cervix) and A549 (lung) cancer cells, using MTT assay, to assess if the flavonoid contributes to the anticancer activity previously proposed for Chromolaena leivensis. The cytotoxic activity of the 3,5,7-trihydroxy-6- methoxy flavone was similar to that obtained for the flavonoid quercetin but was low compared with the positive control vincristine sulphate. The better value of the inhibitory concentration of fifty percent (IC50) 150 μ M, was achieved on SiHa cell line, while the lower activity: 4008 μ M, was obtained on HT29 cancer cell line. However, severe morphological changes were detected on cytoskeleton and nucleus of the SiHa cells detected by immunofluorescence microscopy analysis of cells exposed to the half of the IC50 concentration obtained for the flavonoid. Data indicate that the flavonoid contributes to the anticancer activity of the extracts of leaves from Chromolaena leivensis, and could broadening the spectrum of flavonoids activity against various types of cancer non hormone-dependent.
17

Sinteza i antitumorski potencijal C19-derivatizovanih steroidnih D-homo laktona / Synthesis and antitumor potential of C19-derivatized steroidal D-homo lactones

Kuzminac Ivana 28 September 2018 (has links)
<p>U&nbsp; ovom&nbsp; radu&nbsp; ostvarene&nbsp; su&nbsp; sinteze C19-derivatizovanih&nbsp; steroidnih&nbsp; D-homo laktona.&nbsp; Takođe,&nbsp; sintetisani&nbsp; su&nbsp; i&nbsp; 5,6-halogeni derivati,&nbsp; 5,6-supstituisani&nbsp; kiseonični&nbsp; derivati,<br />kao&nbsp; i&nbsp; 6,19-epoksi&nbsp; steroidi.&nbsp; Za&nbsp; sva&nbsp; sintetisana jedinjenja&nbsp; je&nbsp; utvrđen&nbsp; antitumorski&nbsp; potencijal ispitivanjem&nbsp; njihove&nbsp; oralne&nbsp; bioraspoloživosti, antiproliferativne&nbsp; aktivnosti&nbsp; na&nbsp; &scaron;est&nbsp; ćelijskih linija&nbsp; kancera,&nbsp; vezivanja&nbsp; za&nbsp; odabrane&nbsp; steroidne receptore&nbsp; i&nbsp; inhibitorne&nbsp; aktivnosti&nbsp; na&nbsp; enzim AKR1C3.</p> / <p>In&nbsp; this&nbsp; paper,&nbsp; a&nbsp; synthesis&nbsp; of&nbsp; C19-derivatized steroidal D-homo lactones has been conducted. 5,6-Halogen derivatives, 5,6-substituted oxygen derivatives&nbsp; and&nbsp; 6,19-epoxy&nbsp; steroids&nbsp; were&nbsp; also synthesized.&nbsp; Antitumor&nbsp; potential&nbsp; was determined&nbsp; for&nbsp; all&nbsp; synthesized&nbsp; compounds&nbsp; by examining&nbsp; their&nbsp; oral&nbsp; bioavailability, antiproliferative activity on six cancer cell lines, binding&nbsp; to&nbsp; selected&nbsp; steroid&nbsp; receptors&nbsp; and inhibitor activity on the AKR1C3 enzyme.</p>
18

Synthesis and Biological Evaluation of Various Derivatives of a Broad-Spectrum Anticancer Nucleoside

Shelton, Jadd R. 07 August 2012 (has links) (PDF)
Recently the Peterson lab discovered a promising anticancer adenosine derivative-- 2´,3´-bis-O-tert-butyldimethylsilyl-5´-deoxy-5´-[N-(methylcarbamoyl)amino]-N6-(N-phenylcarbamoyl)adenosine. This compound showed selective toxicity against human colon cancer cells in vitro with LC50's = 6--10 µM. It was hypothesized that the lead compound exerted its cytotoxic effects by interacting with a protein kinase. A systematic Structure Activity Relationship (SAR) was undertaken in an attempt to increase the kinase-binding affinity of the lead compound. Many regions of the lead compound were examined: the N6-phenyl urea moiety, the 5´-N-methyl urea group, the 2´,3´-bis-O-TBS groups, the nucleobase, and the ribose sugar. Results of these studies produced some promising new derivatives. In particular, one analogue exhibited potent cancer cell growth inhibition with an average GI50 of 0.58 μM (NCI-60). In addition, another compound showed selective toxicity for the non-small cell adenocarcinoma cell line NCI-H522 with an LC50 of 10 nM. Efficient methods for the preparation of a wide variety of N6-aryl and -alkyl substituted derivatives were developed. One versatile route involved the installation of an N6-ethoxy carbonyl and subsequent displacement with an alkly- or arylamine. Synthetic routes for the preparation of of a variety of 2´,3´-bis-O-acylated analogues were also developed. Nucleoside mono-, di-, and triphosphate bioisosteres in which the phosphoester or phosphoanhydride have been replaced by an unnatural functional group have been extensively investigated. A simple and efficient method was developed for the preparation of carbamoyl analogues of nucleoside mono-, di-, and triphosphate surrogates. This method uses a modified version of the Kočovský reaction to install mono-, di-, and triphosphate mimics in good to excellent yields (ave = 75%).
19

Dizajn, sinteza i antiproliferativna aktivnost prirodnih citotoksičnih laktona i analoga / Design, synthesis and antiproliferative activity ofnatural cytotoxic lactones and analogues

Srećo Zelenović Bojana 28 February 2013 (has links)
<p>Ostvarene su vi&scaron;efazne sinteze prirodnih citotoksičnih laktona (+)-murikatacina (<strong>1</strong>),<br />(&ndash;)-murikatacina (ent-<strong>1</strong>) i (+)-goniofufurona (<strong>2</strong>), kao i njihovih novih analoga (<strong>3a</strong>,&nbsp; <strong>4</strong>,<br /><strong>5</strong>,&nbsp; <strong>6</strong>,&nbsp; <strong>7</strong>,&nbsp; <strong>8</strong>,&nbsp; <strong>9</strong>,&nbsp; ent-<strong>7&nbsp;</strong>i ent-<strong>9</strong>), polazeći iz&nbsp; D-ksiloze ili iz&nbsp; D-glukoze. Ispitana je&nbsp; in vitro<br />citotoksična aktivnost sintetizovanih prirodnih proizvoda i analoga prema<br />odabranim humanim tumorskim ćelijskim linijama (K562, HL-60, Jurkat, Raji, HT-29,&nbsp;MDA-MB 231 i HeLa), kao i prema ćelijama fetalnih fibroblasta pluća (MRC-5).</p> / <p>Multiphase synthesis of natural cytotoxic lactones&nbsp; (+)-muricatacin (<strong>1</strong>),<br />(&ndash;)-muricatacin (ent-<strong>1</strong>) and (+)-goniofufurone (<strong>2</strong>), as well as synthesis of their<br />analogues (<strong>3a</strong>,&nbsp; <strong>4</strong>,&nbsp; <strong>5</strong>,&nbsp; <strong>6</strong>,&nbsp; <strong>7</strong>,&nbsp; <strong>8</strong>,&nbsp; <strong>9</strong>,&nbsp; ent-<strong>7</strong>and&nbsp; ent-<strong>9</strong>) was achived from&nbsp; D-xylose or<br />D-glucose as starting compounds. In vitro cytotoxic&nbsp; activity of synthetized natural<br />products and analogues against selected human tumour cell lines (K562, HL-60,<br />Jurkat, Raji, HT-29, MDA-MB 231 and HeLa) and against cells of natural foetal lung&nbsp;fibroblasts (MRC-5) was examined.</p>
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Constituintes químicos e atividades antioxidante e antiproliferativa de extratos de Astraea Klotzsch e Croton L. (Euphorbiaceae) / Chemical constituents and antioxidant and antiproliferative activities of Astraea Klotzsch e Croton L. (Euphorbiaceae) extracts

Daniela Carvalho Ogasawara 23 April 2012 (has links)
Plantas da família Euphorbiaceae, são produtoras de um grande e diversificado número de compostos secundários. Os gêneros Croton e Astraea são destaque nessa família, pois, possuem grande importância econômica devido ao seu elevado número de metabólitos secundários. O presente trabalho teve por objetivo ampliar o conhecimento sobre a composição química dos extratos de folhas e caules de seis espécies nativas (gêneros Croton e Astraea) e avaliar as atividades antioxidante e antiproliferativa. Entre os principais compostos encontrados estão &alpha;-cubebeno, &beta;-cariofileno, aromadendreno, óxido de cariofileno, espatulenol, &beta;-eudesmol, elixeno e o 8-isoproprenil-1,5-dimetilciclodeca-1,5-dieno e ledol, nos óleos voláteis; e os tilirosídeo, rutina e vitexina em flavonóides. Os extratos das folhas apresentaram maior eficiência antioxidante do que os extratos dos caules. C. triqueter foi a espécie que demonstrou maior atividade antioxidante tanto para os extratos das folhas quanto para os extratos dos caules. Todas as espécies demonstraram potencial biológico antioxidativo, incentivando assim novas pesquisas com essas espécies. Dos extratos analisados, os mais promissores para atividade antiproliferativa são os de C. campestris (folhas) e A. comosa (folhas e caules), pois apresentaram maior potencial antiproliferativo para as linhagens MCF-7 - mama, NCI-H460 - pulmão e K562 - leucemia. Este trabalho ajudou a ampliar o conhecimento químico e das atividades antioxidante e antiproliferativa sobre o gênero Croton e o gênero Astraea, que possuem enorme potencial biológico e mais de mil espécies distribuídas pelo mundo / Plants of the family Euphorbiaceae are producers of a great and varied number of secondary compounds. The genus Croton and Astraea are highlights in this family because they have great economic importance due to their high number of secondary metabolites. This present work aimed to expand the knowledge about the chemical composition of extracts of leaves and barks of six native species (genus Croton and Astraea) and evaluate the antioxidant and antiproliferative activities. Amongst the main compounds that were found are &alpha;-cubebene, &beta;-cariophyllene, aromadendrene, cariophyllene oxide, spathulenol, &beta;-eudesmol, ledol, elixene and 8-isoproprenyl-1,5-dimethyl-ciclodeca-1,5-diene, in the volatile oils; and the X,Y and Z in flavonoids. The extracts of the leaves presented more antioxidant efficiency than the extracts of the barks. C. triqueter was the species that demonstrated more antioxidant activity for the extracts of both the leaves and the barks. All the species demonstrated antioxidative biological potential, thereby encouraging new researches with these species. ). From the analyzed extracts, the most promising ones for antiproliferative activity are C. campestris (leaves) and A. comosa (leaves and barks), because they presented the highest antiproliferative potential for the cell lines MCF-7 - mammary, NCI-H460 - lung and K562 - leukemia. This work helped to expand the chemical knowledge and the antioxidant and antiproliferative activities of the genus Croton and the genus Astraea, that have great biological potential and more than one thousand species distributed around the world

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