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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.
201

Relação quantitativa entre a estrutura química e o bloqueio da transmissão neuromuscular para série de brometos de [2-(4-benzamido)etil] benzildimetilamônio para-substituídos / Quantitative relationship between chemical structure and neuromuscular transmission blockade for series of [2- (4-benzamido) ethyl] benzyldimethylammonium bromide for para-substituted

Siqueira, Leonardo José Amaral de 07 December 2001 (has links)
Neste trabalho foi preparada uma série de onze brometo de 2-[(4-X-benzamido) etil]benzildimetilamônio, compostos I.1-I.11, série I, estruturalmente análogos à procainamida, não descritos na literatura. Os valores do coeficiente de partição, log Papp7.40, destes compostos foram determinados pelo método shake-flask e foram utilizados como parâmetro lipofílico experimental. Os valores de deslocamento químico do grupamento carbonila, δ 13 C=O, foram determinados e foram determinados cm um espectrómetro de ressonância magnética nuclear a 75 MHz. Adicionalmente, outros parâmetros físico-químicos foram retirados da literatura: π, σp, Τ, R e MR4 ou obtidos por cálculo: log Pcalc e πexp. Os valores da concentração inibitória média (IC50) capaz de reduzir a contração máxima a 50% no período de 15 minutos, foram determinados em preparações nervo frênico-músculo diafragma de camundongos. Para verificar a natureza e a contribuição relativa dos parâmetros físico-químicos frente ao bloqueio da transmissão neuromuscular foi feito uma análise de QSAR, obtendo-se equações, usando análise de regressão linear. As análises de QSAR sugerem uma dependência positiva da lipofilicidade para o bloqueio da transmissão neuromuscular expresso por pIC50, segundo o modelo proposto expresso pela equação: (Ver arquivo PDF). / In this work, a set of eleven 2-[(4-X-benzamido)ethyl]benzyl dimethylammonium bromide structurally related to procainamide was synthesized. The apparent partition coefficient values were determined by means of \"shake-flask method and were taken as lipophilic parameters. The carbonyl chemical shifts values were determined in methanol-d4 and taken as electronic parameters. Additionally, physicochemical parameters were either taken from literature: π, σp, Τ, R e MR4 or calculated: log Pcalc and πexp. The median inhibitory concentration values (IC50) able to reduce maximal contraction to 50% at 15 minutes was determined in phrenic nerve-diafragm muscle preparation of mices. In order to verify the nature and relative contribution of the physicochemical parameters to neuromuscular blockage, QSAR equations were derived using regression analysis. The obtained QSAR model, expressed by the equation below, suggest that lipophilicity term plays an important role to neuromuscular blockage. (See files PDF).
202

Estudo comparativo de parâmetros hipidrofóbicos e, relacionados à ionização, de série de derivados da procaína com atividade bloqueadora neuromuscular / Comparative study of the hydrophobic and ionization parameters of a series of procaine derivatives with neuromuscular blocking activity

Malvezzi, Alberto 13 March 2003 (has links)
O estudo das Relações Quantitativas entre Estrutura química e Atividade biológica (QSAR/QSAR-3D) utilizando diferentes estratégias metodológicas complementares, aplicadas iterativamente, se estende a diferentes áreas de aplicação. Dentre elas destaca-se o planejamento racional de novos fármacos e o estudo de seus mecanismos de ação. Moléculas candidatas a fármacos, geradas em estudos de QSAR-3D, freqüentemente, não se tomam fármacos por apresentarem inadequadas propriedades farmacocinéticas, ou seja, ADME (absorção, distribuição, metabolismo e excreção). Nota-se assim que o conhecimento das propriedades farmacocinéticas de ligantes deve ser uma preocupação presente, em qualquer nível de desenvolvimento de um novo fármaco e ressalta-se a importância do QSAR como uma ferramenta de grande valor, principalmente na compreensão da contribuição das propriedades físico-químicas, identificadas como sendo responsáveis pela atividade. A aplicação do QSAR permite elucidar a natureza e a grandeza das propriedades físico-químicas e estruturais nas interações entre o composto e o seu alvo biológico nos processos farmacocinéticos de ADME (TESTA, 2001; MALVEZZI et al.,, 2001; GAVIRAGHI et al., 2001). Recentemente, em trabalhos realizados em nosso laboratório (SIQUEIRA, 2001), envolvendo a análise de QSAR aplicada aos valores do bloqueio da transmissão neuromuscular determinados para uma série de onze brometos de [2-(4-X-benzamido)etil]benzildimetilamônio substituídos, demonstrou-se tanto a importância da presença de um grupo catiônico terminal como da lipofilicidade para o bloqueio da transmissão neuromuscular. No presente trabalho, visando descrever as interações hidrofóbicas determinantes da potencial atividade bloqueadora neuromuscular, para uma série de dez derivados da procaína, sendo eles: cloretos de 3-(dimetilamino)propiofenona (composto 1); de 3-(dietilamino)propiofenona (composto 2); de 3-(1-pirrolidino)propiofenona (composto 3); de 3-(1-piperidino)propiofenona (composto 4); de 3-(1-morfolino)propiofenona (composto 5); de 3-[1-(4-metilpiperazino)] propiofenona (composto 6); de 3-(c-hexilamino)propiofenona (composto 7); de N-[(N,N-dimetilamino)etil]benzamida (composto 8); de N-[(N,N-dimetilamino )metil]benzamida (composto 9) e, de N-[(N,N-dimetilamino)etil]benzoato (composto 10), por nós sintetizados, determinaram-se os respectivos parâmetros hidrofóbicos e relacionados à ionização (logPappSF; logPnSF; logPiSF; (pKaaq)SF; (pKaoct)SF; logPappHPLC; IogPnPot; IogPiPot; (pKaaq)Pot; logPcalc) obtidos por três métodos experimentais (por Shake-flask; por HPLC e potenciométrico) e por cálculo (programa CLOGP), como modelos de partição. Através da análise comparativa dos valores dos parâmetros hidrofóbicos e relacionados à ionização para a série de dez derivados da procaína (compostos 1-10) sintetizados neste trabalho foi possível constatar que: (i) os valores de IogPcalc modelam, apenas, parcialmente as interações hidrofóbicas refletidas nos valores de logPappSF e de logPappHPLC em valores de pH 3,0 e 10,0, enquanto que as interações hidrofóbicas refletidas nos valores de logPnPot são idealmente modeladas pelos valores de logPcalc; (ii) nas mesmas condições experimentais, os métodos Shake-flask, HPLC e potenciométrico revelam interações hidrofóbicas proporcionais, entretanto, correlações não ideais foram observadas quanto comparados entre si; (iii) os valores de pKaSF , determinados indiretamente por Shake-flask, foram validados pela determinação direta de pKaPot, por potenciometria. Embora o sistema de avaliação da bloqueadora da transmissão neuromuscular tenha sido adequado, a série de compostos estudada não gerou valores válidos para a construção das correspondentes curvas dose-resposta. Os valores obtidos de lC50 para os compostos 3, 4 e 8 da série estudada foram insuficientes, em número, para serem utilizados em uma análise de QSAR. Estudos futuros podem ser realizados com o objetivo de verificar a atividade anestésica local para os compostos da série estudada, avaliando-se a perda da sensibilidade à estimulação sensorial, em cobaias, ou em estudos mais sofisticados de eletrofisiologia (patch clamp). Poder-se-á, assim, fornecer subsídios para elucidar as contribuições relativas da forma catiônica e da forma neutra, respectivamente de compostos ionizáveis com atividade anestésica local. / The scope of Quantitative Structure and Biological Activity Relationships (QSAR/QSAR-3D) studies, using distinct complementary methods, spreads over multiple areas of applicability. Among those, striking are the rational design of new drugs and the enlightenment of their mechanism of action. Candidate molecules, shaped by QSAR-3D analysis, frequently fail to become drugs, and hit the market, due to insufficient pharmacokinetic properties (i.e. absorption, distribution, metabolism and excretion; ADME). Hence, the awareness of pharmacokinetic properties of molecules should be a concern at any leveI of development of new drug candidates. Noteworthy is the use of QSAR as a tool of great value, specially, in the comprehension of the contribution of the physical-chemical properties, responsible for the biological activity. (TESTA, 2001; MALVEZZl et ai., 2001; GAVlRAGHl et ai., 2001). ln this work, aiming to describe the hydrophobic interactions determining the neuromuscular blocking activity of a series of ten procaine derivatives: the hydrochlorides of 3-(dimethylamine)propiophenone (compound 1); of 3-(diethylamine)propiophenone (compound 2); of 3-(1-pirrolidine)propiophenone (compound 3); of 3-(1-piperidine)propiophenone (compound 4); of 3-(1-morfoline)propiophenone (compound 5); of 3-[1-(4-methylpiperazine)]propiophenone (compound 6); de 3-(c-hexilamine)propiophenone (compound 7); de N-[(N,N-dimethylamine)ethyl]benzamide (compound 8); de N-[(N,N-dimethylamine)methyl]benzamide (compound 9) and, of N-[(N,N-dimethylamine)ethyl]benzoate (compound 10), prepared by us, the corresponding hydrophobic parameters (logPappSF; logPnSF; logPiSF; (pKaaq)SF; (pKaoct)SF; logPappHPLC; IogPnPot; IogPiPot; (pKaaq)Pot; logPcalc) were obtained by three experimental methods (Shake-flask; HPLC and potenciometric) and by calculus (CLOGP) as models of partition and distribution. Following the comparative analysis of the values of the hydrophobic parameters determined for the ten compounds of the series of procaine analogs, it was possible to conclude that: (i) the values of IogPcalc reflect only partially, the hydrophobic interactions encoded in the values of logPappSF and logPappHPLC determined in pH values of 3,0 and 10,0; (ii) the values of logPcalc reflect the hydrophobic interactions encoded in the values of logPnPot; (iii) in the same experimental conditions, the methods Shake-flask, HPLC and potenciometric, reflect proportional hydrophobic interactions, although the observed correlations were not ideal when the methods were compared between each other; (iv) the values of pKaSF, determined indirectly by Shake-flask, were validated by the direct measurement of pKaPot, by potentiometry. Even though the system used to measure the neuromuscular blocking actions was adequate, the series of procaine derivatives failed to provide sufficient values to prepare dose-effect curves and proceed with the quantitative structure activity relationships.
203

Izolovanje, strukturna karakterizacija i biološka aktivnost naftnih kiselina iz Vojvođanske nafte / Isolatin, structural characterization and biological activity of naphthenic acids from Vojvodina oil

Grbović Ljubica 04 December 2009 (has links)
<p>Grupno-strukturna analiza naftnih kiselina izolovanih iz srednjih uljnih&nbsp;komercijalnih frakcija vojvođanske nafte &bdquo;Velebit&rdquo; rađena je analizom IR-,&nbsp;<sup>1</sup>H- i&nbsp;<sup>13</sup>C NMR- i ESI-MS spektara niske rezolucije. Određeno je &scaron;est klasa&nbsp;karboksilnih kiselina op&scaron;te molekulske formule C<sub>n</sub>H<sub>2n-Z</sub>O<sub>2</sub>. To su karboksilne&nbsp;kiseline u opsegu masa 240-466 sa 15-31 C atoma u molekulu koje su&nbsp;grupisane u pet cikloalkil Z-serija: monociklična- (C<sub>n</sub>H<sub>2n-2</sub>O<sub>2</sub>, 14.72%),&nbsp;biciklična- (C<sub>n</sub>H<sub>2n-4</sub>O<sub>2</sub>, 34.63%), triciklična- (C<sub>n</sub>H<sub>2n-6</sub>O<sub>2</sub>, 25.03%), tetraciklična- (C<sub>n</sub>H<sub>2n-8</sub>O<sub>2</sub>, 10.04%), pentaciklična klasa karboksilnih kiselina (C<sub>n</sub>H<sub>2n-10</sub>O<sub>2</sub>, 4.99%) i jedna alkanska klasa kiselina sa alkil grupama otvorenog niza (C<sub>n</sub>H<sub>2n</sub>O<sub>2</sub>, 10.57%).</p><p>Razdvajanjem na bazi različite kiselosti i njihove rastvorljivosti u vodi na&nbsp;određenim pH vrednostima u rasponu od pH 2-10 dobijeno je devet užih&nbsp;frakcija kiselina. Ekstrakcijom sa etrom u vodi nerastvornih kiselina u rasponu&nbsp;od po jedne pH jedinice dobijena je sledeća distribucija masa: 9.57% (pH 10),&nbsp;12.69% (pH 9), 5.91% (pH 8), 4.85% (pH 7), 2.44% (pH 6), 11.71% (pH 5),&nbsp;23.94% (pH 4), 16.76% (pH 3) i 10.12% (pH 2). Razdvajanjem kiselina na bazi&nbsp;njihove kiselosti oko 50% mase kiselina ekstrahovano je od pH 2-4, znači u&nbsp;grupi jačih kiselina. Masenom spektrometrijom niske rezolucije ESI-MS na&nbsp;pH 4 vidi se da su u sme&scaron;i kiselina skoncentrisane kiseline sa vi&scaron;e prstenova u&nbsp;alkilnom delu sa maksimumom na tricikličnim kiselinama (36.50%), dok su&nbsp;pojedinačno najzastupljenije tetraciklične strukture kiselina C<sub>20</sub>H<sub>32</sub>O<sub>2</sub>(4.43%) i&nbsp;C<sub>21</sub>H<sub>34</sub>O<sub>2</sub>(4.56%). Na pH 8 biciklične- i triciklične strukture su zastupljene&nbsp;ukupno sa 65.02% sa maksimalno zastupljenim kiselinama sa 20-26 C atoma&nbsp;u molekulu, a izdvajaju se C<sub>22</sub>H<sub>38</sub>O<sub>2</sub> (5.26%)&nbsp;biciklične- i C<sub>24</sub>H<sub>42</sub>O<sub>2</sub>(7.01%)&nbsp;triciklične strukure, a od tetracikličnih struktura kiselina izdvaja se C<sub>24</sub>H<sub>40</sub>O<sub>2&nbsp;</sub>(4.77%). Na pH 10 najzastupljenije izolovane kiseline su aciklične, odnosno&nbsp;masne kiseline zastupljene sa 25.28%, a najdominantnije su strukture&nbsp;C<sub>21</sub>H<sub>42</sub>O<sub>2</sub> (4.83%), dok su ostale klase kiselina ujednačene po svom masenom&nbsp;udelu u odnosu na sastav u ukupnoj polaznoj sme&scaron;i kiselina.&nbsp;Drugi deo rada obuvata derivatizaciju izolovanih prirodnih naftnih kiselina.&nbsp;Sintetizovani su funkcionalni kiseonični metil-, etil-, n-butil-,&nbsp; terc-butil- i&nbsp;benzil-derivati naftnih kiselina kao i funkcionalni azotni derivati: amidi i anilidi&nbsp;naftnih kiselina. Sinteze navedenih estara rađene su klasičnim postupcima i&nbsp;modifikovanom metodom esterifikacije u kiselo-katalizovanim uslovima&nbsp;upotrebom mikrotalasa kao ko-katalizatora, &scaron;to je imalo za cilj skraćenje&nbsp;reakciong vremena i pobolj&scaron;anje ekolo&scaron;kih sintetskih uslova.<br />Modifikacijom sinteze metilnaftenata MT-zagrevanjem 48 puta je skraćeno&nbsp;vreme trajanja sinteze, prinosi ni promenom reakcionih parametara (vreme,&nbsp;snaga MT) nisu bitno promenjeni. Strukturnom analizom ESI-MS spektra&nbsp;polaznih kiselina i metilnaftenata dobijenih metilovanjem naftnih kiselina&nbsp;utvrđeno je da je odnos klasa u dobroj podudarnosti. Prinos estara u ovoj&nbsp;sintezi je 95.47%. Esterifikacija naftnih kiselina etil alkoholom rađena je u&nbsp;uslovima kisele katalize uz konvencionalno zagrevanje (91.76%), a&nbsp;modifikacijom metode MT-zagrevanjem (150 W) reakciono vreme je skaćeno&nbsp;96 puta (92.19%). Esterifikacija naftnih kiselina n-butil alkoholom rađena je uz&nbsp;sumpornu kiselinu kao katalizator i uz konvencionalno zagrevanje (94.24%), a&nbsp;u uslovima MT-zagrevanja (150 W) 72 puta je skraćeno reakciono vreme&nbsp;(61.15%). Sinteza terc-butilnaftenata rađena je prevođenjem naftnih kiselina u&nbsp;hloride a zatim reakcijom sa terc-butil alkoholom nastaju terc-butilnaftenati&nbsp;(80.17%). Modifikovanom metodom klasične reakcije esterifikacije naftnih&nbsp;kiselina terc-butil alkoholom katalizovanom sumpornom kiselinom u uslovima&nbsp;MT-zagrevanja (150 W) ostvaren je prinos od 85.49% a vreme trajanja reakcije&nbsp;je 5 minuta. Sinteza benzilnaftenata rađena je prevođenjem naftnih kiselina u&nbsp;hloride a zatim reakcijom sa benzil alkoholom nastaju benzilnaftenati&nbsp;(84.43%), a modifikovanom metodom klasične kiselo-katalizovane&nbsp;esterifikacije naftnih kiselina benzil alkoholom u uslovima MT-zagrevanja&nbsp;(150 W) ostvaren je prinos od 85.49% uz reakciono vreme od 5 minuta.&nbsp;Sinteza amida naftnih kiselina rađena je iz hlorida reakcijom sa amonijakom.&nbsp;Prinos čistih amida je 65.74%, a reakcija amidacije sa amonijakom trajala je&nbsp;15 minuta. Strukturnom analizom ESI-MS spektra amida naftnih kiselina&nbsp;utvrđen je grupno-strukturni sastav amida. Među strukturama amida naftenskih&nbsp;kiselina takođe su dominantne biciklične- i triciklične strukture, kao i u sme&scaron;i&nbsp;slobodnih kiselina. Sinteza anilida naftnih kiselina rađena je iz hlorida reakcijom sa anilinom. Prinos čistih anilida je 96.48%, a reakcija amidacije anilinom trajala je 30 minuta. Strukturnom analizom ESI-MS spektra anilida naftnih kiselina utvrđen je grupno-strukturni sastav proizvoda, anilida. Među strukturama anilida naftenskih kiselina takođe su dominantne biciklične- i triciklične strukture kao i u sme&scaron;i slobodnih kiselina.</p><p>U trećem delu ovog rada ispitivana je biolo&scaron;ka aktivnost naftnih kiselina&nbsp;auksinskog i giberelinskog tipa, njihov uticaj na ožiljavanje reznica,&nbsp;ukorenjivanje bočnih grana i mikroizdanaka biljaka, na aktivnost biljnih&nbsp;hormona, kao i na usvajanje metalnih jona kod biljaka.&nbsp;</p><p>Aktivnost naftenskih kiselina utvrđena je pomoću tri in vitro&nbsp; biolo&scaron;ka testa.&nbsp;&bdquo;Koleoptil test&rdquo;, rađen je na dva supstrata, odnosno na semenu ozime p&scaron;enice&nbsp;novosadske sorte Partizankai jare p&scaron;enice takođe novosadske sorte Venera.&nbsp;Referentna aktivnost u testu rađena je sa -naftilsirćetnom 3-indolsirćetnom&nbsp;kiselinom. U oba testa ustanovljen je približno isti odnos aktivnosti rastvora&nbsp;naftenskih kiselina i aktivnosti standardnih biljnih hormona. &bdquo;Test inhibicije&nbsp;klijanja&rdquo; semena rađen je sa semenom crne slačice, Brasscia nigra. Najveći&nbsp;uticaj naftenskih kiselina na inhibiciju klijanja postignut je u rasponu&nbsp;koncentracija kiselina od 10<sup>-7</sup>&nbsp;-10<sup>-8&nbsp;</sup>mol/L (0.05-0.01 mg/L). Testovi za &scaron;est užih&nbsp;frakcija dobijenih iz sme&scaron;e ukupnih kiselina razdvajanjem na bazi različite&nbsp;rastvorljivosti pri različitim pH vrednostima pokazuju istu aktivnost kao&nbsp;3-indolsirćetna kiselina (0.5 mg/L), a da je frakcija izdvojena iz vodenog&nbsp;rastvora na pH 7 takođe aktivna ali u poređenju sa 3-indolsirćetnom kiselinom&nbsp;to je 10 puta niža aktivnost. Hormonska aktivnost giberelenskog tipa ispitivanih&nbsp;kalijumovih soli naftenskih kiselina utvrđena je &bdquo;Endosperm testom&rdquo;, u kojem je&nbsp;određivana aktivnost amilaze spektrofotometrijskim praćenjem povećanja&nbsp;koncentracije redukujućih &scaron;ećera u endospermu semena tretiranog ječma i&nbsp;poređena sa aktivno&scaron;ću rastvora giberelinske kiseline (GA3). Rezultati ovih&nbsp;testova pokazuju da delovanjem vodenih rastvora užih frakcija naftenskih&nbsp;kiselina u koncentraciji 1.0 mg/L (3.5 x 10<sup>-6 </sup>mol/L)frakcija izolovana pri pH 8&nbsp;ima aktivnost koja je približno u opsegu aktivnosti giberelina koncentracije&nbsp;10<sup>-2</sup>-10<sup>-3&nbsp;</sup>mg/L.&nbsp;</p><p>Natrijum-naftenati u koncentraciji od 10<sup>-6&nbsp;</sup><br />do 10<sup>-8&nbsp;</sup>mol/L stimuli&scaron;u formiranje&nbsp;adventivnih korenova kod reznica suncokreta pa je broj korenova po biljci 40&nbsp;puta veći kod biljaka koje su bile potopljene u rastvor natrijum-naftenata u&nbsp;odnosu na one koje su bile potopljene u vodu, a sličan efekat utvrđen je i pri&nbsp;tretiranju bočnih grana suncokreta.&nbsp;</p><p>Ožiljavanje drvenastih biljaka rađeno je na reznicama bele topole (Populus&nbsp;alba) i reznicama američke crne topole (Populus deltoides). Uočen je jasan&nbsp;inhibitomi efekat na rast korenčića i izbojka u vodenom medijumu sa 10<sup>-4&nbsp;</sup>mol/L&nbsp;naftenskih kiselina, dok je tretman od 24 časa doprineo većem broju korenčića&nbsp;na donjih 5 cm reznice, kao i ukupnog broja korenčića nego kod kontrole.&nbsp;</p><p>U testu ukorenjivanja mikroizdanaka kod hrizantema najveći broj korenova&nbsp;dobijen je nakon tretmana sa rastvorom koji sadrži 10 &micro;mol/L ukupnih naftenata&nbsp;i tretmanom sa 50 &micro;mol/Lfrakcijom kiselina izolovanom pri pH 7. Oba rezultata&nbsp;su na nivou aktivnosti 3-indolbuterne kiseline koncentracije 10 &micro;mol/L&scaron;to znači&nbsp;da u ovom slučaju frakcionacija nije neophodna.&nbsp;</p><p>Efekti natrijum-naftenata na ukorenjivanje praćeni su merenjem nivoa totalnih&nbsp;peroksidaza i amilaze, &nbsp;kao i sadržaja redukujućih &scaron;ećera i ukupnih proteina u&nbsp;bazalnim delovima reznica bagrema(Rozaszin-AC).&nbsp; Nakon 1; 3 i 6 dana&nbsp;reznice su uzete za biohemijske analize. U svakom slučaju, aktivnosti&nbsp;IAA-oksidaze i amilaze su se povećavale do trećeg dana, &nbsp;a zatim smanjuje.&nbsp;Efekat je bio jače izražen posle tročasovnog tretmana sa natrijum-naftenatima&nbsp;u poređenju sa &scaron;estočasovnim tretmanom i kontrolom. Sadržaj rastvornih&nbsp;proteina je bio povećan jedan dan posle tretmana, smanjen trećeg i ponovo povećan &scaron;estog dana, osim za &scaron;estočasovni tretman natrijum-naftenatima, kada je efekat bio sasvim suprotan.</p><p>Test uticaja naftnih kiselina na nivo kadmijuma u biljkama pokazuje fiziolo&scaron;ko delovanje naftnih kiselina na snižavanje nivoa te&scaron;kih metala u biljci, u ovom slučaju kadmijuma. Ispitivan je efekat niske koncentracije natrijum-naftenata (10<sup>-7&nbsp;</sup>mol/L) na ukupan sadržaj Cd u pojedinim frakcijama interćelijskog prostora kao i unutar ćelija, kao i na neke fiziolo&scaron;ke i biohemijske parametre kod mladih biljaka soje koje su uzgajane u prisustvu kadmijum-hlorida koncentracije 1 mmol/L. Prisustvo naftenata smanjuje sadržaj ukupnog kadmijuma kako u korenu tako i u stablu i listovima u proseku za oko 40% i ublažava &scaron;tetne efekte kadmijuma na aktivnost nitrat-reduktaze kao i na sadržaje fotosintetskih pigmenata.</p><p>Tretman biljaka niskim koncentracijama natrijum-naftenata utiče na&nbsp;akumulaciju nekih esencijalnih elemenata kod mladih biljaka soje. Prisustvo&nbsp;naftenata (10<sup>-7 &nbsp;</sup>mol/L) značajno povećava sadržaj Mn, Fe, Zn i Ni u korenu, ali&nbsp;u stabljici i listovima samo sadržaj Fe i Mn. U korenu, sadržaj Mn je četiri puta&nbsp;veći a sadržaji Fe, Zn i Ni su povećani 17%, 60% i 68%, respektivno.&nbsp;</p><p>Ispitivanja na celeru i mrkvi su potvrdila da uticaj naftenata na mineralnu&nbsp;ishranu zavisi od primenjenog elementa i da je način preuzimanja određenih&nbsp;jona različit, &scaron;to ima za posledicu ili povećanje ili smanjenje sadržaja pojedinih&nbsp;jona u nekim delovima biljaka. Mlade biljke celera i mrkve, gajene u hranljivom&nbsp;medijumu, tretirane su natrijumovim solima naftenskih kiselina (10<sup>-7&nbsp;</sup>mol/L)&nbsp;folijarno ili prisustvom u hranljivom medijumu. Jedino je tretman putem&nbsp;prisustva naftenata u hranljivom medijumu smanjio svežu masu korena i&nbsp;nadzemnog dela oko 20% kod obe biljke.Oba tretmana uticala su na sadržaj&nbsp;Fe, Cu, Mn, Mg i Ca kod biljaka celera i Fe, Mn, Zn i Na kod biljaka mrkve.&nbsp;Kod biljaka celera do&scaron;lo je do smanjenja sadržaja navedenih nutrienata dok je&nbsp;u korenu biljaka mrkve do&scaron;lo do povećanja sadržaja Fe za 45%, Mn za 70% i&nbsp;Zn za 37%. Kod ovih biljaka prisustvo naftenata u hranljivom medijumu dovelo&nbsp;do smanjenja mase korenova i nadzemnih delova, &scaron;to je potpuno suprotno od&nbsp;rezultata dobijenih kod biljaka soje.&nbsp; Folijarnim tretmanom je značajno<br />povećana masa nadzemnog samo kod celera.</p> / <p>Group-structural analysis of naphthenic acids isolated from middle&nbsp;commercial fractions of Vojvodina oil &bdquo;Velebit&rdquo; was performed with the&nbsp;analysis of IR-,<br /><sup>1</sup>H- and&nbsp;<sup>13</sup>C NMR- and ESI-MS low resolution spectrums.&nbsp;Six classes of carboxylic acids of the general molecular formula C<sub>n</sub>H<sub>2n-Z</sub>O<sub>2&nbsp;</sub>were determined. These are carboxylic acids with mass range of 240-466&nbsp;with 15-31 C atoms in molecule which are grouped in five cycloalkyl&nbsp;<span style="font-size: 12px;">Z-series: monocyclic- (C<sub>n</sub>H<sub>2n-2</sub>O<sub>2</sub>, 14.72%), bicyclic- (C<sub>n</sub>H<sub>2n-4</sub>O<sub>2</sub>, 34.63%),&nbsp;</span><span style="font-size: 12px;">tricyclic- (C<sub>n</sub>H<sub>2n-6</sub>O<sub>2</sub>, 25.03%), tetracyclic- (C<sub>n</sub>H<sub>2n-8</sub>O<sub>2</sub>, &nbsp;10.04%), pentacyclic&nbsp;</span><span style="font-size: 12px;">class of carboxylic acids (C<sub>n</sub>H<sub>2n-10</sub>O<sub>2</sub>, 4.99%) and one alyphatic class of&nbsp;</span><span style="font-size: 12px;">acids with open chain alkyl groups (C<sub>n</sub>H<sub>2n</sub>O<sub>2</sub>, 10.57%).</span></p><p>By fractioning on the basis of different levels of acidity and their solubility in&nbsp;water with pH values ranging from pH 2-10 nine subfractions of acids were&nbsp;obtained. By extraction with ether in water undissolved acids in the range of&nbsp;one pH unit the following distribution of mass was performed: 9.57%&nbsp;(pH 10), 12.69% (pH 9), 5.91% (pH 8), 4.85% (pH 7), 2.44% (pH 6), 11.71%&nbsp;(pH 5), 23.94% (pH 4), 16.76% (pH 3) and 10.12% (pH 2). By fractioning&nbsp;acids on the basis of their acidity about 50% of acid &nbsp;mass was extracted at&nbsp;pH 2-4, i.e., in the group of stronger acids. Low resolution mass&nbsp;spectrometry ESI-MS shows that at pH 4 acids with more rings in the alkyl&nbsp;<br />section were concentrated in the mixture with maximum at tricyclic acids&nbsp;(36.50%), while individually tetracyclic acid structures C<sub>20</sub>H<sub>32</sub>O<sub>2</sub> (4.43%) and&nbsp;C<sub>21</sub>H<sub>34</sub>O<sub>2&nbsp;</sub>(4.56%) were most prominent. At pH 8 bicyclic- and tricyclic&nbsp;structures are represented &nbsp;together by 65.02% with acids with 20-26 C&nbsp;atoms in molecule being represented the most, and C<sub>22</sub>H<sub>38</sub>O<sub>2</sub>&nbsp; (5.26%)&nbsp;bicyclic- and C<sub>24</sub>H<sub>42</sub>O<sub>2</sub>(7.01%) tricyclic structures stand &nbsp;out, while with&nbsp;tertacyclic acid structures C<sub>24</sub>H<sub>40</sub>O<sub>2</sub> (4.77%) stands out. At pH 10 most&nbsp;represented isolated acids are acyclic, i.e., fatty acids which are&nbsp;represented by 25.28%, with the most dominant C<sub>21</sub>H<sub>42</sub>O<sub>2&nbsp;</sub>structures&nbsp;(4.83%), while the other classes &nbsp;of acids are well balanced in their mass&nbsp;share in relation to the composition of the overall initial acid mixture.</p><p>The second part of this work deals with derivatization of the isolated natural&nbsp;naphthenic acids. Functional oxygen methyl-, ethyl-, n-butyl-, tert-butyl and&nbsp;benzyl-derivatives of naphthenic acids as well as functional nitrogen&nbsp;derivatives: amides and anilides of naphthenic acids were synthesized. The&nbsp;syntheses of the above mentioned esters were performed by conventional&nbsp;methods and by a modified method of esterification in acid-catalyzed&nbsp;conditions using microwaves as a co-catalyst with the aim of shortening the&nbsp;reaction time and improving the ecological synthetic conditions.&nbsp;</p><p>By modification of methyl naphthenates synthesis using MT-heating the&nbsp;time period for synthesis is reduced 48 times and the yield does not&nbsp;significantly change even after the reaction parameters (time, MT power)&nbsp;have been altered. Using structural analysis of ESI-MS spectrum of initial&nbsp;carboxylic acids and the methyl naphthenates obtained through methylation&nbsp;of naphthenic acids it was establishedthat the class ratio shows great&nbsp;compatibility. The esters yield in this synthesis is 95.47%. The esterification&nbsp;of naphthenic acids with ethyl alcohol done under the conditions of acid&nbsp;catalysis with conventional heating (91.76%), and with the modified method&nbsp;MT-heating (150 W) the reaction time is reduced 96 times (92.19%). The&nbsp;esterification of naphthenic acids with n-butyl alcohol was performed using&nbsp;sulphuric acid as a catalyst with conventional heating (94.24%), and under&nbsp;MT-heating conditions (150 W) reaction time was 72 times&nbsp; shorter&nbsp;(61.15%). The synthesis of&nbsp; tert-butyl naphthenates was performed by&nbsp;conversion of naphthenic acids into chlorides, followed by the reaction with&nbsp;tert-butyl alcohol which resulted in tert-butyl naphthenates (80.17%). By the&nbsp;modified method of conventional reaction of esterification of naphthenic&nbsp;acids using tert-butyl alcohol catalysed with sulphuric acid in MT-heating&nbsp;conditions (150 W) the yield was 85.49% and reaction time was 5 minutes.&nbsp;The synthesis of benzyl naphthenates was performed by conversion of&nbsp;naphthenic acids into chlorides, followed by a reaction with benzyl alcohol&nbsp;which produces benzyl naphthenates (84.43%), whereas the modified&nbsp;method of conventional acid-catalysed esterification of naphthenic acids&nbsp;using benzyl alcohol under MT-heating (150 W) conditions the yield was&nbsp;85.49% with the reaction time of 5 minutes.&nbsp;</p><p>The synthesis of naphthenic acid amides was done from chlorides by&nbsp;reaction with ammonia. The yield of pure amides was 65.74%, and the&nbsp;reaction of amidation with ammonia lasted for 15 minutes. The structural&nbsp;analysis of ESI-MS spectrum of naphthenic acid amides determined the&nbsp;group-structural composition of amides. With the structures of amides of&nbsp;naphthenic acids bicyclic- and tricyclic structures are also dominant, as in&nbsp;the mixture of free acids. The synthesis of naphthenic acid anilides were&nbsp;performed from chloride by reacting with aniline. The yield of pure anilides&nbsp;<br />was 96.48%, and the reaction of amidatation lasted for 30 minutes. The&nbsp;structural analysis of ESI-MS spectrum of naphthenic acid anilides&nbsp;determined the group-structural composition of anilide products. With the&nbsp;structures of anilides of naphthenic &nbsp;acids bicyclic- and tricyclic structures&nbsp;are also dominant, as in the mixture of free acids.</p><p>The third part of this work tests the biological activity of naphthenic acids of&nbsp;auxine and gibberellinic type, their influence on the rooting of cuttings,&nbsp;lateral branches and microshoots of plants, on the activity of plant&nbsp;hormones as well as on the metal ions uptake by plants.&nbsp;</p><p>The activity of naphthenic acids was determined using three in vitro&nbsp;biological tests. &bdquo;Koleoptil test&rdquo;, was done on two substrates, namely the&nbsp;seed of winter wheat of the Partizankasort and the spring wheat of the&nbsp;Venerasort. The referential activity in the test was performed with&nbsp;&alpha;-naphthylacetic- and 3-indolacetic acid. Both tests showed approximately&nbsp;the same ratio of activity of naphthenic acid solutions and standard plant&nbsp;hormones. &bdquo;Germination Inhibition Test&rdquo; of the seed was performed using&nbsp;<br />Brasscia nigraseed. The greatest influence of naphthenic acids to&nbsp;germination inhibition was achieved in the acid concentration ranging from&nbsp;10<sup>-7</sup>-10<sup>-8&nbsp;</sup>mol/L (0.05-0.01 mg/L). The tests for six narrow fractions obtained&nbsp;from the overall mixture of acids through fractioning on the basis of different&nbsp;solubility at different pH values show the same activity as 3-indolacetic acid&nbsp;(0.5 mg/L), with the fraction isolated from the aqueous solution at pH 7 also&nbsp;active but in comparison to 3-indolacetic acid this activity was 10 times&nbsp;lower. Hormone activity of gibberellinic type of the potassium salts of&nbsp;naphthenic acids was determined using &ldquo;Endosperm Test&rdquo; where amylase&nbsp;<br />activity was determined by spectrophotometric measuring of the increase of&nbsp;the concentration of reducing sugars in endosperm in the treated barley&nbsp;seed which was then compared to the activity of the gibberellic acid solution&nbsp;(GA3).&nbsp; The results of these tests indicate that the activity of aqueous&nbsp;solutions of narrow fractions of naphthenic acids in the concentration of&nbsp;1.0 mg/L (3.5 x 10<sup>-6&nbsp;</sup>mol/L)the fraction isolated &nbsp;at pH 8 has the activity&nbsp;which is approximately within the range of activities of gibberellin of the&nbsp;concentration of 10<sup>-2</sup>-10<sup>-3&nbsp;</sup>mg/L.&nbsp;</p><p>Sodium salts of naphthenic acids in concentrations of 10<sup>-6&nbsp;</sup>do 10<sup>-8&nbsp;</sup>mol/L&nbsp;stimulated formation of adventitious roots in&nbsp;<span style="font-size: 12px;">sunflower cuttings even by a&nbsp;</span><span style="font-size: 12px;">factor of 40 compared with control, the effect being also observed lateral&nbsp;</span><span style="font-size: 12px;">branches of interspecies sunflower hybrids. The obtained results suggest&nbsp;</span><span style="font-size: 12px;">the possibility of using naphthenic acids as a means for rooting of plant&nbsp;</span><span style="font-size: 12px;">cuttings.</span></p><p>Rooting of hardwood plants was investigated on the cuttings of white poplar&nbsp;(Populus alba) and black poplar (Populus deltoides). The distinct inhibitory&nbsp;effect on the root and shoot growth in water culture was detected in the&nbsp;concentration of naphtenic acids 10<sup>-4&nbsp;</sup>mol/L, but 24-hour treatment raised&nbsp;the number roots on undermost 5 cm of the cutting, as well as the total&nbsp;number of roots, comparing to the control.</p><p>In the test of rooting microshoots ofchrysanthemum the highest number of&nbsp;<span style="font-size: 12px;">roots was achieved after the treatment with solution containing 10 &micro;mol/L of&nbsp;</span><span style="font-size: 12px;">total napthenates, as &nbsp;well as after the treatment with fraction of naphthenic&nbsp;</span><span style="font-size: 12px;">acids which was isolated at pH &nbsp;7 in concentration of 50 &micro;mol/L. Both results&nbsp;</span><span style="font-size: 12px;">are on the level of activity of 3-ndolbutyric acid in concentration of 10 &micro;mol/L&nbsp;</span><span style="font-size: 12px;">which suggests that in this case ractionation is not necessary.</span></p><p>The effects of sodium naphthenates on rooting were investigated by&nbsp;measuring the level of total peroxidases and amylase, along with the&nbsp;contents of reducing sugars and total proteins in basal parts of cuttings of&nbsp;black locust (Rozaszin-AC). After 1; 3 and 6 days cuttings were taken for&nbsp;biochemical analysis. In all cases, the activities of IAA-oxidase and amylase&nbsp;increased to the third day and showed a decrease afterwards. The effect&nbsp;was more pronounced after the three-hour treatment with sodium&nbsp;naphthenates, compared to the six-hour treatment and control. The content&nbsp;of soluble proteins increased one dayafter the treatment and decreased to&nbsp;the third and again increased to the sixth day, an exception being the&nbsp;six-hour treatment with sodium naphthenate, when the effect was&nbsp;completely opposite.</p><p>The test of naphthenic acids influence on the level of cadmium in plants&nbsp;showed physiological activity of naphthenic acids on the decrease of the&nbsp;level of heavy metals, &nbsp;in this case cadmium, in the plant. The effect of low&nbsp;concentrations (10<sup>-7&nbsp;</sup>mol/L) of sodium naphthenate on total content of Cd in&nbsp;the intercellular space and inside cells, as &nbsp;well as on some physiological&nbsp;and biochemical parameters of young soybean plants grown in the&nbsp;presence of 1 mmol/L solution of cadmium chloride was investigated.&nbsp;Presence of naphthenate reduced in average by 40 % content of total and&nbsp;intracellular Cd in root, stem and leaves and alleviated the harmful effect of&nbsp;<br />Cd on activity of nitrate reductase and content of photosynthetic pigments.</p><p>Treatment of soybean plants with low concentrations of sodium&nbsp;naphthenate influenced the accumulation ofsome essential elements by the&nbsp;young plants. The presence of naphthenates (10<sup>-7&nbsp;</sup>mol/L) significantly&nbsp;increased content of Mn, Fe, Zn and Ni in root, but in stem and leaves&nbsp;increased only contents of Fe and Mn. Inroot, the content of Mn increased&nbsp;four times while contents of Fe, Zn and Ni increased by 17%, &nbsp;60% and 68%&nbsp;respectively compared to the control.</p><p>Investigations on celery and carrot&nbsp; confirmed that the influence of&nbsp;naphthenates on mineral nutrition depends on the applied element and that&nbsp;the way of uptake of certain ions is different, which results in either increase&nbsp;or decrease of the contents of some ions in certain parts of plants. Young&nbsp;plants of celery and carrot, were grown in the nutrient medium and treated&nbsp;with sodium salts of naphthenic acids (10<sup>-7&nbsp;</sup>mol/L) over the leaves or with its&nbsp;presence in the nutrient medium. Only the treatment based on the &nbsp;presence&nbsp;of naphthenates in the nutrient medium resulted in the decrease of the fresh&nbsp;mass of root and aboveground part by about 20% for both plants. Both&nbsp;treatments had influence on the content of Fe, Cu, Mn, Mg and Ca in the&nbsp;plants of celery and Fe, Mn, Zn and Na in the plants of carrots. In the plants&nbsp;of celery the content of the mentioned nutrients was decreased, while in the&nbsp;root of plants of carrot &nbsp;the content was increased, Fe by 45%, Mn by 70%&nbsp;and Zn by 37%. With these plants &nbsp;the presence of naphthenates in the&nbsp;nutrient medium caused the reducing roots and aboveground parts, which is&nbsp;completely opposite from the results obtained with soybean plants. The&nbsp;treatment by leaves significantly increased the mass of aboveground part&nbsp;only with celery.</p>
204

Valorisation en synthèse organique d'éco-catalyseurs hétérogènes régénérables à partir de matériaux verts cultivés sur des sols contaminés / Valorization in organic synthesis of heterogeneous eco-catalysts produced from green materials grown on contaminated soils.

Dufrénoy, Pierrick 14 December 2018 (has links)
Les activités des anciennes industries métallurgiques spécialisées dans la production et la transformation de plomb, de zinc ou d’autres métaux ont engendré une pollution métallique importante des sols selon la localisation de ces derniers. Des études actuelles proposent ainsi des solutions de requalification de ces sols via des processus de phytoremédiation afin de valoriser au maximum les plantes cultivées sur ces sols contaminés. Ce projet de thèse a ainsi été réalisé dans le but de valoriser des écocatalyseurs hétérogènes régénérables. Ces derniers sont obtenus à partir des plantes cultivées sur des sols contaminés dans la synthèse organique pour la production de composés à haute valeur ajoutée. Les sols contaminés utilisés dans ce projet proviennent de la région Hauts-de-France (Auby et Noyelles-Godault). Dans cette optique, quatre types de réactions ont été testés pour valider l’efficacité et la recyclabilité des écocatalyseurs : La réaction d’aminolyse, La réaction de Friedel-Crafts, La transformation d’aza-Michael, et enfin La réaction de transestérificationDes écocatalyseurs riches en zinc (EcoZn), obtenus à partir de la biomasse végétale de ray-grass (Lolium perenne L.), ont été caractérisés par des méthodes physico-chimiques puis validités leurs critères d’efficacité et de recyclabilité. Ceux-ci ont ainsi permis de synthétiser plusieurs séries de composés à activité anti-inflammatoires connus (piroxicam, méloxicam, idrocilamide) et de nouveaux, des inhibiteurs de la farnésyltransférase (à visée anticancéreuse ou pour combattre des maladies orphelines telles que la progéria) ou encore de découvrir un nouvel accepteur d’aza-Michael. / The activities of the former metallurgy industries specialized in the production and processing of lead, zinc or other metals have resulted in significant metallic pollution of soils depending on their location. Current studies propose solutions for the requalification of these soils through the phytoremediation processes in order to maximize the value of plants grown on these contaminated soils. This PhD thesis project was thus realized with the aim of valorizing regenerative heterogeneous ecocatalysts. The latter were obtained from the plants cultivated on contaminated soils in organic synthesis for the production of high value added molecules. The contaminated soils used in this project came from the Hauts-de-France region (Auby and Noyelles-Godault). In this light, four types of reactions have been tested to validate the efficiency and recyclability of ecocatalysts: The aminolysis reaction The Friedel-Crafts reaction The aza-Michael transformation The transesterification reactionThe zinc-rich ecocatalysts (EcoZn), obtained from the plant biomass of ryegrass (Lolium perenne L.), were characterized by physicochemical methods and validated their efficiency and recyclability criteria. The latter were successfully used to reach various series of compounds with anti-inflammatory activity known (piroxicam, meloxicam, idrocilamide) and new, inhibitors of farnesyltransferase (for anticancer purpose or to fight orphan diseases such as progeria) or to discover a new aza-Michael acceptor.
205

Quimioterápicos potencialmente ativos em endemias tropicais e tuberculose: estudos de QSAR na série de 5-nitroderivados benzidrazídicos e o planejamento de pró-fármacos de ação prolongada / Chemotherapeutics potentially active in tropical endemic diseases and tuberculosis: QSAR studies in the series of benzhydrazide 5-nitroderivatives and the planning of long-acting prodrugs

Daniela Gonçales Rando 19 May 2005 (has links)
Malária, doença de Chagas e leishmaniose, consideradas doenças negligenciadas, e tuberculose, infecção bacteriana reemergente, que grassa em diversas regiões do mundo, constituem-se grandes desafios médico-sociais para os países acometidos. Nitroderivados são substâncias utilizadas na terapêutica como antimicrobianos de amplo espectro. O mecanismo de ação proposto para estes compostos engloba a redução do grupo nitro por nitrorredutases inespecíficas, levando à produção de radicais livres. Estes, altamente reativos, reagiriam, por sua vez, com macromoléculas, organelas, membranas e mesmo ácidos nucléicos danificando-os irreversivelmente e levando o microrganismo - bactérias e parasitos -- à morte. No caso particular da doença de Chagas, a redutase envolvida na redução seria a tripanotiona redutase, que poderia ser inibida por estes compostos. Compostos 5-nitro-2-heterocíclicos benzidrazídicos são derivados estudados como antibacterianos e antiparasitários. Sabe-se que alterações na posição 2 dos anéis 5-nitrofurânicos interferem com o potencial redox do grupo nitro e, assim, com a atividade biológica destes compostos. Com base nesta informação e supondo que a estrutura destas moléculas seja completamente ressonante, propôs-se a síntese de série de derivados 5-nitro-heterocíclicos benzidrazídicos variando-se a estrutura dos análogos em dois pontos principais: substituições no anel benzênico da estrutura e o tipo de anel heterocíclico ligado diretamente ao grupo nitro. Com relação ao tipo de anel ligado ao grupo nitro foram propostos derivados 5-nitrofurânicos e 5-nitrotiofênicos. Quanto aos substituintes no anel benzênico propuseram-se derivados mono e dissubstituídos nas posições meta e para de acordo com suas contribuições eletrônicas e hidrofóbicas para o sistema. Para tanto foram utilizados os parâmetros físico-químicos &#960; e &#963;. Para analisar o efeito das modificações na atividade biológica destes compostos aplicou-se a metodologia de Topliss como ponto de partida para a análise quantitativa, QSAR-2D, pelo método misto de Hansch-Free Wilson. A biblioteca planejada foi obtida por síntese paralela em solução, empregando-se sintetizadores paralelos automatizados. Foram obtidos 56 derivados, que foram purificados, caracterizados estruturalmente e, então, analisados frente a quatro microrganismos: Plasmodium falciparum, Leishmania donovani, Trypanosoma cruz e Mycobacterium tuberculosis. Os estudos de QSAR-2D revelaram importância significativa do tipo de anel heterocíclico ligado ao grupo nitro para a atividade destes compostos. Não foi possível, entretanto, obter correlação das atividades com as substituições realizadas no anel aromático, o que levou ao arrolamento de diferentes hipóteses, incluindo aquelas relativas à deslocalização eletrônica nas estruturas estudadas. Estas hipóteses, bem como os resultados sobre a influência do tipo de anel heterocíclico ligado ao grupo nitro nas atividades biológicas estudadas fornecem subsídios para novos projetos de pesquisa dedicados à exploração das informações obtidas neste trabalho. / Malaria, Chagas\' disease and leishmaniasis, considered as neglected diseases, and tuberculosis, reemerging bacterial infection disseminated worldwide, are medical-social challenges for the countries involved. Nitroderivatives are therapeutic compounds used as broad spectrum antimicrobial drugs. The most accepted mechanism of action of these compounds is based on nitro group reduction by unspecific nitroreductases or, in case of Chagas\' disease, inhibition of tripanotiona redutase. Free radical species are formed from this reduction, which can react with macromolecules, organelles, membranes and nucleic acids of microorganisms leading them to death. The 5-nitro-2-heterocyclic benzhydrazide derivatives are nitrofuran analogs that have been tested as antibacterial and antiprotozoal drugs. As already known, modifications in position 2 of 5-nitroheterociclic rings can interfere with nitro group redox potential and then with their biological activities. Based on this information and considering these compound structures are completely conjugated structures, we suggested the synthesis of a library of 5-nitro-2-heterocyclic benzhydrazide derivatives with two main points of structural modification: the substituents in benzenic ring and the kind of heterocyclic ring directly linked to the nitro group. The former was achieved by suggesting mono and dissubstituted analogs based on their hydrophobic and electronic contributions whose values were obtained from physico-chemical parameters &#960; and &#963;. Nitrofurans and nitrothiophenes were elected to study the influence of the heterocyclic ring directly linked to the nitro group. Topliss methodology was used as a starting point to 2D-QSAR mixed quantitative method through Hansch-Free Wilson analysis. The designed library was synthesized by solution phase parallel synthesis using automated parallel synthesizers. Fifty-six analogs were synthesized, purified, characterized and biologically analyzed against four microorganisms: Plasmodium falciparum, Leishmania donovani, Trypanosoma cruzi e Mycobacterium tuberculosis. The 2D-QSAR studies provided information about the significative influence of the kind of heterocyclic ring on the biological activity of the series. Nevertheless, it was not possible to obtain information about the influence of different substitutions on benzene ring and different hypothesis were advanced to explain the electronic distribution in the structures herein studied. These hypotheses as well as the data about the influence of the kind of heterocyclic ring directly linked to the nitro group on the biological activities studied deserve to be tested and explored in future researches.
206

Produtos naturais marinhos: identificação de metabólitos fenólicos halogenados na macroalga Bostrychia tenella (Rhodomelaceae, Rhodophyta) e potencial biológico de micro-organismos endofíticos associados / Marine natural products: halophenolic metabolites identification in the seaweed Bostrychia tenella (Rhodomelaceae, Rhodophyta) and biological potential of associated endophytic microorganisms

Rafael de Felício 07 October 2010 (has links)
O ambiente marinho desponta como uma fonte natural importante devido à sua fantástica diversidade orgânica, que permanece praticamente inexplorada. Abordagens químicas e biológicas de organismos marinhos, atualmente, representam uma área de pesquisa ampla e promissora, visto a constante descoberta de diversos metabólitos com propriedades medicinais variadas, além de um arsenal metabólico praticamente ilimitado. Algas vermelhas, com destaque para a família Rhodomelaceae, são exímias produtoras de metabólitos halogenados aos quais são atribuídos importantes atividades biológicas. Micro-organismos marinhos e/ou endofíticos são apontados como os alvos mais promissores para descoberta de novos fármacos. Neste contexto, o presente trabalho descreve a identificação de metabólitos secundários da macroalga Bostrychia tenella (Rhodomelaceae, Rhodophyta), a qual possui poucos relatos na literatura a respeito de seu metabolismo secundário, bem como o potencial biológico de micro-organismos endofíticos associados a esta espécie. O estudo químico da espécie B. tenella coletada nos costões rochosos da Praia da Fortaleza (Ubatuba-SP) proporcionou a identificação, por meio de análises via CG-EM (fração acetato), de 63 metabólitos dos quais 39 são substâncias apolares de cadeias carbônicas longas (ex. ácidos graxos e ésteres, esteróides, dentre outros) e 24 são metabólitos fenólicos, incluindo 17 halofenóis clorados, bromados e iodados. Destas 24 substâncias, até o presente momento, três são inéditas, nove são inéditas como produtos naturais, quatro são inéditas em algas marinhas e seis são inéditas para o gênero Bostrychia. Adicionalmente, 45 linhagens de micro-organismos endofíticos foram isoladas da alga Bostrychia tenella, das quais 10 foram cultivadas em meio sólido arroz, proporcionando a obtenção de extratos brutos e frações orgânicas. Apesar das frações de B. tenella não terem exibido atividade biológica, extratos e frações dos micro-organismos endofíticos associados a esta espécie apresentaram-se ativos em todos os ensaios realizados: citotoxicidade utilizando células tumorais HL-60, HCT-8 e SF-295, antifúngico utilizando fitopatógenos Cladosporium cladosporioides e C. sphaerospermum, antibacteriano utilizando Staphylococcus aureus e Klebsiella pneumoniae, e inibição da degranulação mastocitária utilizando células RBL-2H3. O presente trabalho contribuiu para aumento do conhecimento sobre o metabolismo secundário da alga Bostrychia tenella e proporcionou a descoberta do potencial biológico de micro-organismos endofíticos associados a esta alga, atribuindo a esta espécie relevância química e microbiológica para o estudo de produtos naturais marinhos. / The marine environment appears as an important natural source due to its fantastic organic diversity, which practically remains unexplored. Chemical and biological approaches concerning marine organism, currently, represent an ample and promising research area, since there are a constant metabolite discovery with a variety of medicinal properties, besides the limitless metabolic armory. Red seaweeds, with distinction for the Rhodomelaceae family, are exempt of halogenated metabolites producers which are attributed important biological activities. Marine and/or endophytic microorganisms are pointed as the most promising targets with respect to discovery of new pharmaceuticals. In this context, the present work describes the secondary metabolites identification from seaweed Bostrychia tenella (Rhodomelaceae, Rhodophyta), as well as the biological potential of associated endophytic microorganisms. The chemical study of B. tenella species collected in the rocky shore of Praia de Fortaleza (Ubatuba-SP) provided the identification, by means of GC-MS analyses (acetate fraction), of 63 metabolites, which 39 consisted of nonpolar substances containing a long carbonic chains (fatty acids, esters, steroids, amongst others) and 24 were phenolic compounds, including 17 chlorinated, bromated and iodized halophenols. Related to these 24 substances, until the present moment, three are unknown, nine are unknown as natural products, four are unknown in seaweeds and six are unknown in the Bostrychia genus. Additionally, 45 endophytic microorganism strains had been isolated from B. tenella, from which 10 were cultivated in solid rice medium, providing several crude extracts and fractions. Although the B. tenella fractions did not show biological potential, extracts and fractions from endophytic microorganism associates to this species presented biological activity in all of evaluated assays: cytotoxicity using tumor cells HL-60, HCT-8 and SF-295, antifungal in Cladosporium cladosporioides and C. sphaerospermum, antibacterial using Staphylococcus aureus and Klebsiella pneumoniae, and mast cell degranulation inhibition using RBL-2H3 cells. The present work contributed for the secondary metabolism knowledge increase regarding Bostrychia tenella species, and demonstrated the endophytic microorganism biological potential, attributing to this species chemical and microbiological relevance for the marine natural products research.
207

Produtos naturais marinhos: identificação de metabólitos fenólicos halogenados na macroalga Bostrychia tenella (Rhodomelaceae, Rhodophyta) e potencial biológico de micro-organismos endofíticos associados / Marine natural products: halophenolic metabolites identification in the seaweed Bostrychia tenella (Rhodomelaceae, Rhodophyta) and biological potential of associated endophytic microorganisms

Felício, Rafael de 07 October 2010 (has links)
O ambiente marinho desponta como uma fonte natural importante devido à sua fantástica diversidade orgânica, que permanece praticamente inexplorada. Abordagens químicas e biológicas de organismos marinhos, atualmente, representam uma área de pesquisa ampla e promissora, visto a constante descoberta de diversos metabólitos com propriedades medicinais variadas, além de um arsenal metabólico praticamente ilimitado. Algas vermelhas, com destaque para a família Rhodomelaceae, são exímias produtoras de metabólitos halogenados aos quais são atribuídos importantes atividades biológicas. Micro-organismos marinhos e/ou endofíticos são apontados como os alvos mais promissores para descoberta de novos fármacos. Neste contexto, o presente trabalho descreve a identificação de metabólitos secundários da macroalga Bostrychia tenella (Rhodomelaceae, Rhodophyta), a qual possui poucos relatos na literatura a respeito de seu metabolismo secundário, bem como o potencial biológico de micro-organismos endofíticos associados a esta espécie. O estudo químico da espécie B. tenella coletada nos costões rochosos da Praia da Fortaleza (Ubatuba-SP) proporcionou a identificação, por meio de análises via CG-EM (fração acetato), de 63 metabólitos dos quais 39 são substâncias apolares de cadeias carbônicas longas (ex. ácidos graxos e ésteres, esteróides, dentre outros) e 24 são metabólitos fenólicos, incluindo 17 halofenóis clorados, bromados e iodados. Destas 24 substâncias, até o presente momento, três são inéditas, nove são inéditas como produtos naturais, quatro são inéditas em algas marinhas e seis são inéditas para o gênero Bostrychia. Adicionalmente, 45 linhagens de micro-organismos endofíticos foram isoladas da alga Bostrychia tenella, das quais 10 foram cultivadas em meio sólido arroz, proporcionando a obtenção de extratos brutos e frações orgânicas. Apesar das frações de B. tenella não terem exibido atividade biológica, extratos e frações dos micro-organismos endofíticos associados a esta espécie apresentaram-se ativos em todos os ensaios realizados: citotoxicidade utilizando células tumorais HL-60, HCT-8 e SF-295, antifúngico utilizando fitopatógenos Cladosporium cladosporioides e C. sphaerospermum, antibacteriano utilizando Staphylococcus aureus e Klebsiella pneumoniae, e inibição da degranulação mastocitária utilizando células RBL-2H3. O presente trabalho contribuiu para aumento do conhecimento sobre o metabolismo secundário da alga Bostrychia tenella e proporcionou a descoberta do potencial biológico de micro-organismos endofíticos associados a esta alga, atribuindo a esta espécie relevância química e microbiológica para o estudo de produtos naturais marinhos. / The marine environment appears as an important natural source due to its fantastic organic diversity, which practically remains unexplored. Chemical and biological approaches concerning marine organism, currently, represent an ample and promising research area, since there are a constant metabolite discovery with a variety of medicinal properties, besides the limitless metabolic armory. Red seaweeds, with distinction for the Rhodomelaceae family, are exempt of halogenated metabolites producers which are attributed important biological activities. Marine and/or endophytic microorganisms are pointed as the most promising targets with respect to discovery of new pharmaceuticals. In this context, the present work describes the secondary metabolites identification from seaweed Bostrychia tenella (Rhodomelaceae, Rhodophyta), as well as the biological potential of associated endophytic microorganisms. The chemical study of B. tenella species collected in the rocky shore of Praia de Fortaleza (Ubatuba-SP) provided the identification, by means of GC-MS analyses (acetate fraction), of 63 metabolites, which 39 consisted of nonpolar substances containing a long carbonic chains (fatty acids, esters, steroids, amongst others) and 24 were phenolic compounds, including 17 chlorinated, bromated and iodized halophenols. Related to these 24 substances, until the present moment, three are unknown, nine are unknown as natural products, four are unknown in seaweeds and six are unknown in the Bostrychia genus. Additionally, 45 endophytic microorganism strains had been isolated from B. tenella, from which 10 were cultivated in solid rice medium, providing several crude extracts and fractions. Although the B. tenella fractions did not show biological potential, extracts and fractions from endophytic microorganism associates to this species presented biological activity in all of evaluated assays: cytotoxicity using tumor cells HL-60, HCT-8 and SF-295, antifungal in Cladosporium cladosporioides and C. sphaerospermum, antibacterial using Staphylococcus aureus and Klebsiella pneumoniae, and mast cell degranulation inhibition using RBL-2H3 cells. The present work contributed for the secondary metabolism knowledge increase regarding Bostrychia tenella species, and demonstrated the endophytic microorganism biological potential, attributing to this species chemical and microbiological relevance for the marine natural products research.
208

Enhancing ecosystem services in vineyards to improve the management of Botrytis cinerea

Jacometti, Marco Alexander Azon January 2007 (has links)
Organic mulches and cover crops mulched in situ were assessed for their effects on B. cinerea primary inoculum and disease levels in inflorescences at flowering and/or bunches at harvest. Organic mulches were used to enhance biological degradation of vine debris to reduce levels of B. cinerea primary inoculum the following season. Four mulch types (anaerobically and aerobically fermented marc (grape pressings), inter-row grass clippings and shredded office paper) were applied under ten-year-old Riesling vines in a ten-replicate randomized block design in New Zealand over two consecutive years. Plastic mesh bags, each containing naturally infected vine debris, were placed under vines on bare ground (control) and at the soil-mulch interface, in winter (July) 2003 and 2004. In each year, half the bags were recovered at flowering (December) and the remainder at leaf plucking (February), for assessment of B. cinerea sporulation from the vine debris and debris degradation rate. Bait lamina probes, which measure soil biological activity, were placed in the soil-mulch interface three weeks before each of the two bag-recovery dates in both years and were then removed and assessed at the same times as were the bags. All mulches led to a reduction in B. cinerea sporulation. This reduction was significantly correlated with elevated rates of vine debris decomposition and increased soil biological activity. Over both years, compared with the controls, all treatments gave a 3-20-fold reduction in B. cinerea sporulation, a 1.6-2.6-fold increase in vine debris degradation and in the two marc and the paper treatments, a 1.8-4-fold increase in activity of soil organisms. The mulches also altered vine characteristics and elevated their resistance to B. cinerea through changes to the soil environment. Functional soil biological activity, as measured by Biolog Ecoplates and bait lamina probes, was increased 2-4 times in the two marc and paper treatments, compared with the control, an effect relating to the elevated soil moisture and reduced temperature fluctuations under these mulches. Soil nutrient levels and the C:N ratios were also affected in these treatments. The mulched paper lowered vine canopy density by up to 1.4 times that of the other treatments, an effect which probably led to elevated light penetration into the canopy and consequent increased canopy temperature, photosynthesis and lowered canopy humidity. These changes to soil and vine characteristics increased grape skin strength by up to 10% in the paper treatment and sugar concentrations by 1.2-1.4 °Brix in the two marc and paper treatments. The severity of B. cinerea infections in the anaerobic marc, aerobic marc and paper treatments were reduced to 12%, 3% and 2.2% of the control, respectively, in field assessments averaged over two consecutive harvests. Cover crops mulched in situ had similar effects to those of the organic mulches, increasing soil biological activity and reducing B. cinerea primary inoculum and the severity of B. cinerea infection in grapes at harvest (2006). Inter-row phacelia and ryegrass were mulched in winter 2005 and compared with a bare ground control, under 10-year-old Chardonnay vines in a ten-replicate randomized block design. Functional soil biological activity increased by 1.5-4.5 times in the two cover crop treatments compared with the control, an effect possibly related to elevated soil moisture in these treatments. This increase in soil moisture and soil biological activity increased vine debris degradation, reduced B. cinerea primary inoculum on the debris and decreased B. cinerea severity at flowering (December 2005) and harvest (April 2006). These results show the potential of organic mulches and cover crops mulched in situ to enhance soil ecosystem services and improve the sustainability of viticultural practices.
209

Studie av koldioxidgradienter i havets ytskikt

Söderholm, Sofia January 2009 (has links)
<p><strong><p>Studie av koldioxidgradienter i havets ytskikt</p><p>Sofia Söderholm</p></strong></p><p>Denna studie bygger på ett nyligen utvecklat instrument som har mätt koldioxidkoncentrationer på tre olika djup i vattnet samt en nivå i luften. Då detta instrument var oprövat i vatten har en utvärdering av mätmetodens lämplighet för vattenmätningar utförts. Syftet med mätningarna var att undersöka ytvattnets vertikala koldioxidgradient för att med hjälp av denna kunna beskriva flödet av koldioxid mellan hav och atmosfär bättre. Detta flöde är en viktig del av den globala kolcykeln och en djupare förståelse för koldioxidflödets beteende kan i framtiden bidra till mer noggranna klimatprognoser. Hur de beräknade flödena från profilinstrumentet påverkas av temperaturgradienterna i vattnets ytskikt har även det studerats. Mätningarna utfördes i vattnet utanför mätstationen på Östergarnsholm, öster om Gotland. En del av studien fokuserar på de horisontella koldioxidgradienterna i ytvattnet som erhållits genom fartygsdata.</p><p>Instrumentet som har använts vid mätningarna bygger på hydrofoba, luftgenomträngliga membran och förefaller fungera mycket väl i vatten. Vid vindhastigheter som inte är högre än 3 - 4 m/s kan tydliga koldioxidgradienter i vattnets ytskikt ses, men detta samband behöver verifieras med en större mängd mätdata. Temperaturgradienten i vattnets ytskikt har ingen större påverkan på vare sig koldioxidgradienten eller flödet av koldioxid och dess effekt kan försummas i detta fall. De horisontella koldioxidgradienterna påverkas huvudsakligen av temperaturen, den biologiska aktiviteten samt transport av vattenmassor. På en större skala kan tydliga effekter av temperaturen på koldioxidhalterna ses och på en mindre skala samt nära kuster och under våren är den biologiska aktiviteten dominerande.</p><p><em><p>Nyckelord: Koldioxidgradient, koldioxidflöde, temperaturgradient, hydrofoba luftgenomträngliga membran, transferhastighet, vindhastighet, biologisk aktivitet.</p></em></p> / <p><strong><p>A study regarding the carbon dioxide gradients in the surface water.</p><p>Sofia Söderholm</p></strong></p><p>This study is based on a recently developed instrument that measures the concentration of carbon dioxide at three different depths in the water and one level in the air. Since this instrument has not previously been used for measurements in water, an evaluation regarding the usefulness of the instruments for measurements in water was made. The purpose of the measurements was to study the vertical gradient of carbon dioxide in the surface water and to describe the vertical flux of carbon dioxide between the ocean and the atmosphere in an improved way. This flux is an important part of the global carbon cycle and a deeper understanding of the behavior of the air-sea exchange of carbon dioxide could contribute to more accurate forecasts of the future climate. The impact on the calculated carbon dioxide flux by the temperature gradients in the surface waters was also analyzed. The measurements were performed in the waters outside of the island of Östergarnsholm, east of Gotland. Part of the study focuses on the horizontal carbon dioxide in the surface water, which was obtained by ship data.</p><p>The instrument used when performing the measurements is based on hydrophobic, air-permeable membranes and appears to function very well in water. During wind speeds below 3 - 4 m/s distinct carbon dioxide gradients can be seen for the investigated data, but more data is needed to quantify this gradient for different situations. The temperature gradient in the surface water doesn't have a significant effect on the carbon dioxide gradient or the flow of carbon dioxide, and the effect of the temperature gradient can in this particular case be neglected. The horizontal gradients of carbon dioxide are mainly affected by temperature, biological activity and transportation of water mass. On a larger scale the effects of temperature on the concentrations of carbon dioxide are visible and on a smaller scale along with the coastal areas and during springtime, the biological activity is the dominating influence.</p><p><em><p>Keywords: Carbon dioxide gradient, carbon dioxide flux, temperature gradient, hydrophobic airpermeable membranes , transfer velocity, wind speeds, biological activity.</p></em></p>
210

Studie av koldioxidgradienter i havets ytskikt

Söderholm, Sofia January 2009 (has links)
Studie av koldioxidgradienter i havets ytskikt Sofia Söderholm Denna studie bygger på ett nyligen utvecklat instrument som har mätt koldioxidkoncentrationer på tre olika djup i vattnet samt en nivå i luften. Då detta instrument var oprövat i vatten har en utvärdering av mätmetodens lämplighet för vattenmätningar utförts. Syftet med mätningarna var att undersöka ytvattnets vertikala koldioxidgradient för att med hjälp av denna kunna beskriva flödet av koldioxid mellan hav och atmosfär bättre. Detta flöde är en viktig del av den globala kolcykeln och en djupare förståelse för koldioxidflödets beteende kan i framtiden bidra till mer noggranna klimatprognoser. Hur de beräknade flödena från profilinstrumentet påverkas av temperaturgradienterna i vattnets ytskikt har även det studerats. Mätningarna utfördes i vattnet utanför mätstationen på Östergarnsholm, öster om Gotland. En del av studien fokuserar på de horisontella koldioxidgradienterna i ytvattnet som erhållits genom fartygsdata. Instrumentet som har använts vid mätningarna bygger på hydrofoba, luftgenomträngliga membran och förefaller fungera mycket väl i vatten. Vid vindhastigheter som inte är högre än 3 - 4 m/s kan tydliga koldioxidgradienter i vattnets ytskikt ses, men detta samband behöver verifieras med en större mängd mätdata. Temperaturgradienten i vattnets ytskikt har ingen större påverkan på vare sig koldioxidgradienten eller flödet av koldioxid och dess effekt kan försummas i detta fall. De horisontella koldioxidgradienterna påverkas huvudsakligen av temperaturen, den biologiska aktiviteten samt transport av vattenmassor. På en större skala kan tydliga effekter av temperaturen på koldioxidhalterna ses och på en mindre skala samt nära kuster och under våren är den biologiska aktiviteten dominerande. Nyckelord: Koldioxidgradient, koldioxidflöde, temperaturgradient, hydrofoba luftgenomträngliga membran, transferhastighet, vindhastighet, biologisk aktivitet. / A study regarding the carbon dioxide gradients in the surface water. Sofia Söderholm This study is based on a recently developed instrument that measures the concentration of carbon dioxide at three different depths in the water and one level in the air. Since this instrument has not previously been used for measurements in water, an evaluation regarding the usefulness of the instruments for measurements in water was made. The purpose of the measurements was to study the vertical gradient of carbon dioxide in the surface water and to describe the vertical flux of carbon dioxide between the ocean and the atmosphere in an improved way. This flux is an important part of the global carbon cycle and a deeper understanding of the behavior of the air-sea exchange of carbon dioxide could contribute to more accurate forecasts of the future climate. The impact on the calculated carbon dioxide flux by the temperature gradients in the surface waters was also analyzed. The measurements were performed in the waters outside of the island of Östergarnsholm, east of Gotland. Part of the study focuses on the horizontal carbon dioxide in the surface water, which was obtained by ship data. The instrument used when performing the measurements is based on hydrophobic, air-permeable membranes and appears to function very well in water. During wind speeds below 3 - 4 m/s distinct carbon dioxide gradients can be seen for the investigated data, but more data is needed to quantify this gradient for different situations. The temperature gradient in the surface water doesn't have a significant effect on the carbon dioxide gradient or the flow of carbon dioxide, and the effect of the temperature gradient can in this particular case be neglected. The horizontal gradients of carbon dioxide are mainly affected by temperature, biological activity and transportation of water mass. On a larger scale the effects of temperature on the concentrations of carbon dioxide are visible and on a smaller scale along with the coastal areas and during springtime, the biological activity is the dominating influence. Keywords: Carbon dioxide gradient, carbon dioxide flux, temperature gradient, hydrophobic airpermeable membranes , transfer velocity, wind speeds, biological activity.

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