No description available.

No description available.

Basic and clinical research documents the benefits of dietary milled flaxseed (MFX), a rich source of alpha-linolenic acid (ALA) and lignans, in the attenuation of risk factors key to regulating cardiovascular disease (CVD) progression. ALA has antihypertensive properties and the lignan metabolites, enterodiol (END) and enterolactone (ENL), have antioxidative potential. The effectiveness of these bioactives to reduce risk factors of CVD may be dependent upon their plasma concentrations. To study this, we first designed and validated a method using supported liquid extraction and gas chromatography/mass spectrometry to isolate and quantify enterolignans in plasma. Applying this technique, we examined MFX doses of 10-40 g/d administered to healthy, younger adults (18-49 years of age) for 4 weeks. Ten g/d was sufficient to significantly increase circulating ALA (1.5 fold) and enterolignans (5-31 fold). There was no significant dose-dependent response. In another investigation, younger (18-29 years of age) and older (45-69 years of age) healthy adults were studied to determine if age influenced enterolignan metabolism. CVD is associated with advanced age but older people may not be able to obtain lignan metabolites from dietary MFX. Following 4 weeks of MFX consumption, both age groups increased plasma total enterolignans (END + ENL) with no between-group differences. This suggested that older and younger adults metabolize MFX lignans equally. A final study assessed MFX bioactives in plasma of peripheral artery disease patients >40 years of age. Plasma enterolignans increased 10-50 fold and ALA 1-2 fold after only one month of MFX ingestion. Dietary MFX also attenuated total (11%) and LDL (15%) cholesterol in these patients after 1-6 months of administered MFX compared to placebo. The attenuation in cholesterol was due to the high fiber content of flaxseed, and not to ALA and enterolignans, despite their marked increase in circulation. MFX did not interfere with cholesterol-lowering medications but instead decreased cholesterol levels beyond the effects of medications alone. To conclude, dietary supplementation with MFX resulted in an increase in plasma enterolignan and ALA concentrations in healthy younger and older adults and in patients with pre-existing CVD. The cholesterol-lowering benefits of MFX were additional to cholesterol-lowering drugs and likely attributed to MFX fiber. / May 2016

by Lun Kue Sun. / Includes bibliographical references / Thesis (M.Ph.)--Chinese University of Hong Kong, 1986

A presente dissertação descreve o isolamento e elucidação estrutural de alguns constituíntes químicos do tegumento de V. elongata, espécie envolvida em usos etnofarmacológicos. 0 extrato clorofórmico forneceu além de ésteres alifáticos e triglicerídeos dois policetídeos do tipo diarilalcanoílicos: 1-(2\',6\'- Dihidroxi-4\'-metoxifeni1)-12-fenil-dodecan-1-ona (inédito) e 1-(2\',4\',6\'- Trihidroxi-3\',4\'-dihidrofeni1)-11-fenil-undecan-1-ona (conhecido) ; três lignanas furofufurânicas: (1R,2S,5R,6R)-6-(3\',4\'-Dimetoxifeni1)-2-(3\",4\"-metilenodioxifeni1)-3,7-dioxabiciclo‌3.3.0‌ octano (fargesina); (1R,2S,5R,6R)-2,6-Bis-(3\",4\" -dimetoxifeni1)-3,7-dioxabiciclo- ‌3.3.0‌ octano (epieudesmina) e (1R,2S,5R,6S)-2,6-Bis-(3\",4\" -dimetoxifenil)-3,7-dioxabiciclo ‌3.3.0‌ octano (eudesmina); e duas neolignanas tetraidrofurânicas: (1S,2S,5R,6R)-1-Metil - 2-(3\",4\"-metilenodioxifeni1)-5-(α-hidroxi-3\" 1,4\'\"-dimetoxibenzil)-tetraidrofurano (inédita) e (15,2S,5R,6R)-1-Metil-2-(3\",4\"-dimetoxifeni1)-5-(α-hidroxi-3\'\",4\'\"-dimetoxibenzil)-tetraidrofurano (magnostelina A). 0 isolamento dos constituíntes químicos foi baseada em técnicas cromatográficas e a elucidação estrutural em métodos espectrométricos usuais (UV, IV, DRO, RMN de 1H e de 13C). A comprovação da estrutura do policetídeo Ve-6 foi baseada na aromatização por desidratação em meio ácido. A determinação da configuração relativa das neolignanas tetreidrofurânicas foi baseada em estudo envolvendo o reagente de deslocamento Eu(fod)3. A determinação da configuração absoluta foi baseada na conversão em uma neolignana tetralínica e comparação de sua curva de DRO com compostos modêlos. / The present dissertation describe isolation and structural elucidation of some chemicals constituents of tegument from V. elongata, involved in ethnopharmacology uses. The chloroform extract afford besides aliphatics esthers and triglycerides, two poliketides of the diarylalkanoyl type: 1-(2\',6\'-Dihydroxypheny1)-12-dodecan-l-one and 1-(2\',4\',6\'-Trihydroxy-3\',5\'-dihydropheny1)-11-phenyl-undecan-1-one, the former is unknown and the latter is known; three furofuranic lignans type: (1R, 2S, 5R, 6R) -6- (3\',4\'-Dimethoxypheny1)-2-(3\",4\" -methylenedioxypheny1)-3,7-dioxabicycle‌3.3.0‌ octane (fargesin); (1R,2S,5R,6R)-2,6-Bis-(3\",4\"-dimethoxypheny1)-3,7-dioxabicycle‌3.3.0‌octane (epieudesmin) and (1R,2S,5R,6S)-2,6-Bis-(3\",4\" -dimethoxypheny1)-3,7-dioxabicycle‌3.3.0‌ octane (eudesmin); and two neolignans of the tetrahydrofuranic type:(1S,2S,5R,6R)-1-Methy1-2-(3\",4\" -methylenedioxypheny1)-5-(α-hydroxy-3\'\",4\'\" -dimethoxybenzy1)-tetrahydrofuran (unknow) and (1S,2S,5R,6R)-1-Methy1-2-(3\",4\" -dimethoxypheni1)-5-(α-hydroxy-3\'\",4\'\"-dimethoxybenzy1)-tetrahydrofuran (magnostelin A). Isolation of chemical constituents was based on chromatographic techniques and structural determination on usual spectrometric methods (UV, IR, MS, ORD, 1H and 13C NMR). Poliketyde skeleton was elucidated by acid catalized dehydration yielding a diarylic compound. The relative structure of tetrahydrofuranic neolignans was based in lanthanide induced shift reagent. The absolute configuration was based on chemical transformation to tetralinic neolignan and comparison of its ORD curve with model compounds curves.

Application of radical reactions in the organic synthesis for the formation of carbon-carbon bond has dramatically increased over the last fifteen years by virtue of their high degree of chemo-, regio- and stereoselectivity. The present thesis entitled "Radical Cyclisation based Approaches to 9-pupukeanone and Lignan Precursors" describes the application of radical reactions in the synthesis of isotwistane carbon framework present in pupukeananes, and b-arylmethylbutyrolactones, established precursors of various types of lignans. For convenience, the results are presented in two chapters, & ( I ) Radical annulation approach to chiral analogues of 9-pupukeanones; (2) Synthesis of (+-)-enterolactone and lignan precursors; and an appendix entitled 'Chiral synthons from (R)- carvone'. In each Chapter the compounds are sequentially numbered (bold and double underlined), and references are marked sequentially as superscripts and listed at the end of the Chapter. All the figures were obtained by direct xerox of the originaltNMR and muss spectra, and in some of them uninformative areas have been cut to save the space.

Thesis (Ph.D.)--Kent State University, 2007. / Title from PDF t.p. (viewed Mar. 11, 2009). Advisor: Angelo L. DeLucia. Keywords: human papillomavirus, E6 oncogene, lignan, p53, apoptosis. Includes bibliographical references (p. 132-144).

Made available in DSpace on 2014-06-11T19:29:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-08-17Bitstream added on 2014-06-13T20:38:31Z : No. of bitstreams: 1 pereira_mdp_me_araiq_parcial.pdf: 203577 bytes, checksum: ca9c116bb7cb586faf5887975ac7eb5b (MD5) Bitstreams deleted on 2014-11-14T12:17:01Z: pereira_mdp_me_araiq_parcial.pdf,Bitstream added on 2014-11-14T12:17:46Z : No. of bitstreams: 1 000718773.pdf: 4442978 bytes, checksum: 32aaf6f2d0d8b0678b1e8f805a2bd0b1 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Holostylis reniformis sintetiza uma variedade de compostos, incluindo seco lignanas e sesquiterpenos. Em busca de potenciais compostos antimaláricos, novos estudos fitoquímicos dos extratos de raízes foram realizados. Este trabalho descreve o isolamento de quatorze compostos por meio de técnicas cromatográficas, principalmente por CCD e CC, e CLAE. Estes compostos foram caracterizados por métodos espectrométricos, especialmente por experimentos de RMN e medidas de rotação óptica específica. A partir dos extratos de raízes de H. reniformis três sesquiterpenos novos, 4,5-seco-guaiano (7-epi-11-hidroxichabrolidiona A, XIV), uma lactona de nove membros (holostilactona, XV), e uma megastigmana [(6S,9S,7E)- 6,9-di-hidroxi-10-(2'-hidroxietoxi)-4,7-megastigmadien-3-ona, XVI], juntamente com uma nova lignana [(7R, 7'R,8S,8'S)-8,8'-dimetil-4-hidroxi-3',4',5,7-tetrametil-2,7'- ciclolignana, VIII] foram isoladas. Além disso, os compostos conhecidos sitosterol (I), alantoína (XI), e a lignana furânica futokadsurin C (IX) foram obtidos. Visando estudos posteriores sobre estrutura e atividade antimalárica, o composto (7'R,8S,8'S)-8,8'-dimetil-3',4',4,5-tetrametil-2,7'-ciclolignan-7-ona foi submetido a transformações químicas gerando dois derivados. / Holostylis reniformis can synthesize a variety of seco compounds including lignans and sesquiterpenes. In search of potential antimalarial compounds further phytochemical studies on the root extracts were carried out. This work describes the isolation of 14 compounds by chromatographic techniques, mainly by TLC, CC, and HPLC. These compounds were characterized by spectrometric methods, particularly by NMR experiments and optical rotation measurements. From the root extracts of H. reniformis three new sesquiterpenes, 4,5-seco-guaiane (7-epi-11- hydroxychabrolidione A, XIV), a nine-membered lactone (holostylactone, XV), and a megastigmane [(6S,7E,9S)-6,9-dihydroxy-10-(2'-hydroxyethoxy)-4,7-megastigmadien -3-one, XVI], together with a new lignan [(7R,7′R,8S,8′S)-8,8′-dimethyl-4-hydroxy- 3′,4′,5,7-tetramethoxy-2,7′-cyclolignan, VIII] were isolated. In addition, the known compounds sitosterol (I), allantoin (XI), and a tetrahydrofuran lignans futokadsurin C (IX) were obtained. (7′R,8S,8′S)-8,8′-dimethyl-3′,4′,4,5-tetramethoxy-2,7′-cyclolignan-7-one was subjected to chemical transformations into two derivatives for further structure and antimalarial activity studies

Orientador: Lucia Maria Xavier Lopes / Banca: André Luiz Meleiro Porto / Banca: Monica Tallarico Pupo / Resumo: Holostylis reniformis sintetiza uma variedade de compostos, incluindo seco lignanas e sesquiterpenos. Em busca de potenciais compostos antimaláricos, novos estudos fitoquímicos dos extratos de raízes foram realizados. Este trabalho descreve o isolamento de quatorze compostos por meio de técnicas cromatográficas, principalmente por CCD e CC, e CLAE. Estes compostos foram caracterizados por métodos espectrométricos, especialmente por experimentos de RMN e medidas de rotação óptica específica. A partir dos extratos de raízes de H. reniformis três sesquiterpenos novos, 4,5-seco-guaiano (7-epi-11-hidroxichabrolidiona A, XIV), uma lactona de nove membros (holostilactona, XV), e uma megastigmana [(6S,9S,7E)- 6,9-di-hidroxi-10-(2'-hidroxietoxi)-4,7-megastigmadien-3-ona, XVI], juntamente com uma nova lignana [(7R, 7'R,8S,8'S)-8,8'-dimetil-4-hidroxi-3',4',5,7-tetrametil-2,7'- ciclolignana, VIII] foram isoladas. Além disso, os compostos conhecidos sitosterol (I), alantoína (XI), e a lignana furânica futokadsurin C (IX) foram obtidos. Visando estudos posteriores sobre estrutura e atividade antimalárica, o composto (7'R,8S,8'S)-8,8'-dimetil-3',4',4,5-tetrametil-2,7'-ciclolignan-7-ona foi submetido a transformações químicas gerando dois derivados. / Abstract: Holostylis reniformis can synthesize a variety of seco compounds including lignans and sesquiterpenes. In search of potential antimalarial compounds further phytochemical studies on the root extracts were carried out. This work describes the isolation of 14 compounds by chromatographic techniques, mainly by TLC, CC, and HPLC. These compounds were characterized by spectrometric methods, particularly by NMR experiments and optical rotation measurements. From the root extracts of H. reniformis three new sesquiterpenes, 4,5-seco-guaiane (7-epi-11- hydroxychabrolidione A, XIV), a nine-membered lactone (holostylactone, XV), and a megastigmane [(6S,7E,9S)-6,9-dihydroxy-10-(2'-hydroxyethoxy)-4,7-megastigmadien -3-one, XVI], together with a new lignan [(7R,7′R,8S,8′S)-8,8′-dimethyl-4-hydroxy- 3′,4′,5,7-tetramethoxy-2,7′-cyclolignan, VIII] were isolated. In addition, the known compounds sitosterol (I), allantoin (XI), and a tetrahydrofuran lignans futokadsurin C (IX) were obtained. (7′R,8S,8′S)-8,8′-dimethyl-3′,4′,4,5-tetramethoxy-2,7′-cyclolignan-7-one was subjected to chemical transformations into two derivatives for further structure and antimalarial activity studies / Mestre

Orientador: Fernando Antonio Santos Coelho / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-11T20:25:29Z (GMT). No. of bitstreams: 1 Trazzi_Giordano_D.pdf: 4999245 bytes, checksum: f94ecef7fd826cf4fd4109674ac33860 (MD5) Previous issue date: 2008 / Resumo: Lignanas são produtos naturais produzidos por plantas, cuja diversidade estrutural e pronunciada atividade biológica têm atraído o interesse acadêmico e industrial há mais de um século, a exemplo do fármaco antitumoral Etoposide® (Sandoz), derivado semi-sintético da podofilotoxina, uma lignana natural até hoje comercialmente obtida por extração vegetal. Dentre as rotas de síntese de lignanas, as mais eficazes empregam uma b-benzil-g-butirolactona como intermediário-chave da estratégia. Nesse contexto, propusemos o emprego da reação de Morita-Baylis-Hillman (MBH) para o preparo de a-(aril-hidroximetil)- acrilatos (adutos de MBH) e sua utilização como materiais de partida para a síntese de b-(aril-silaniloximetil)-g-butirolactonas, novos intermediários-chave para a síntese de lignanas. Partindo paralelamente do piperonal, do 6-bromo-piperonal e da vanilina, empregamos a reação de MBH para preparar os a-(aril-hidroximetil)- acrilatos correspondentes, e então os utilizamos na preparação de suas respectivas b-(aril-silaniloximetil)-g-butirolactonas, de forma diastereosseletiva e com rendimentos globais de 56% a 69%, em 4 etapas a partir dos adutos de MBH. A b-(piperonil-silaniloximetil)-g-butirolactona foi empregada com alta eficiência na síntese total das lignanas naturais (±)-yateína, (±)-podorrizol e (±)-epi-podorrizol. A b-(6-bromo-piperonil-silaniloximetil)-g-butirolactona permitiu a preparação de um intermediário avançado para uma nova proposta sintética para a (±)- podofilotoxina. A b-(guaiacil-silaniloximetil)-g-butirolactona, obtida a partir da vanilina, e um intermediário chave para a síntese racemica da porção aglicona do medusasídeo A, uma nova lignana da classe dos dibenzilbutanodiois, cuja síntese ainda não foi descrita / Abstract: Lignans are plant-produced natural products, which structural diversity and pronounced biological activity has being attracting the interest of academy and industry through the entire last century, taking as example the antineoplasic drug Etoposide® (Sandoz), a semi-synthetic derivative of podophyllotoxin, a natural lignan which is, up to date, commercially obtained only by vegetal extraction. Among the routes of synthesis to lignans, the most efficient ones uses a b-benzyl- g-butyrolactone as the key intermediate. In this scenario, we have envisaged the use of the Morita-Baylis-Hillman reaction to synthetize a-(aryl-hydroxymethyl)- acrylates (MBH adducts) and it¿s use as starting materials to the synthesis of b-(aryl-silanyloxymethyl)-g-butyrolactones, new key intermediates to the synthesis of lignans. Starting alongside from piperonal, b-bromo-piperonal and vanillin, we used the MBH reaction to prepare the corresponding a-(aryl-hydroxymethyl)-acrylates (MBH adducts), and used it in the preparation of it¿s corresponding b-(arylsilanyloxymethyl)- g-butyrolactones, in a diastereoselective way and with global yields from 56% to 69% in four steps. The b-(piperonyl-silanyloxymethyl)-g- butirolactone obtained was used with high efficiency in the synthesis of natural lignans (±)-yatein, (±)-podorrizol and (±)-epi-podorrizol. The b-(6-bromo-piperonylsilanyloxymethyl)- g-butirolactone obtained allowed the preperation of an advanced intermediate to a new synthetic strategy to (±)-podophyllotoxyn. The b-(guaiacylsilanyloxymethyl)- g-butirolactone obtained is a key intermediate to the racemic synthesis of medusaside A aglycone, a new dibenzylbutanediol lignan whose synthesis was not described yet / Doutorado / Quimica Organica / Doutor em Ciências