969 resultados para p-menth-3-ene-1,2,8-triol
Resumo:
A series of 1,2,3,4-tetrahydrobenzo[h][1,6]naphthyridines differently substituted at positions 1, 5, and 9 have been designed from the pyrano[3,2-c]quinoline derivative 1, a weak inhibitor of acetylcholinesterase (AChE) with predicted ability to bind to the AChE peripheral anionic site (PAS), at the entrance of the catalytic gorge. Fourteen novel benzonaphthyridines have been synthesized through synthetic sequences involving as the key step a multicomponent Povarov reaction between an aldehyde, an aniline and an enamine or an enamide as the activated alkene. The novel compounds have been tested against Electrophorus electricus AChE (EeAChE), human recombinant AChE (hAChE), and human serum butyrylcholinesterase (hBChE), and their brain penetration has been assessed using the PAMPA-BBB assay. Also, the mechanism of AChE inhibition of the most potent compounds has been thoroughly studied by kinetic studies, a propidium displacement assay, and molecular modelling. We have found that a seemingly small structural change such as a double O → NH bioisosteric replacement from the hit 1 to 16a results in a dramatic increase of EeAChE and hAChE inhibitory activities (>217- and >154-fold, respectively), and in a notable increase in hBChE inhibitory activity (> 11-fold), as well. An optimized binding at the PAS besides additional interactions with AChE midgorge residues seem to account for the high hAChE inhibitory potency of 16a (IC50 = 65 nM), which emerges as an interesting anti-Alzheimer lead compound with potent dual AChE and BChE inhibitory activities.
Resumo:
A series of 1,2,3,4-tetrahydrobenzo[h][1,6]naphthyridines differently substituted at positions 1, 5, and 9 have been designed from the pyrano[3,2-c]quinoline derivative 1, a weak inhibitor of acetylcholinesterase (AChE) with predicted ability to bind to the AChE peripheral anionic site (PAS), at the entrance of the catalytic gorge. Fourteen novel benzonaphthyridines have been synthesized through synthetic sequences involving as the key step a multicomponent Povarov reaction between an aldehyde, an aniline and an enamine or an enamide as the activated alkene. The novel compounds have been tested against Electrophorus electricus AChE (EeAChE), human recombinant AChE (hAChE), and human serum butyrylcholinesterase (hBChE), and their brain penetration has been assessed using the PAMPA-BBB assay. Also, the mechanism of AChE inhibition of the most potent compounds has been thoroughly studied by kinetic studies, a propidium displacement assay, and molecular modelling. We have found that a seemingly small structural change such as a double O → NH bioisosteric replacement from the hit 1 to 16a results in a dramatic increase of EeAChE and hAChE inhibitory activities (>217- and >154-fold, respectively), and in a notable increase in hBChE inhibitory activity (> 11-fold), as well. An optimized binding at the PAS besides additional interactions with AChE midgorge residues seem to account for the high hAChE inhibitory potency of 16a (IC50 = 65 nM), which emerges as an interesting anti-Alzheimer lead compound with potent dual AChE and BChE inhibitory activities.
Resumo:
A series of 1,2,3,4-tetrahydrobenzo[h][1,6]naphthyridines differently substituted at positions 1, 5, and 9 have been designed from the pyrano[3,2-c]quinoline derivative 1, a weak inhibitor of acetylcholinesterase (AChE) with predicted ability to bind to the AChE peripheral anionic site (PAS), at the entrance of the catalytic gorge. Fourteen novel benzonaphthyridines have been synthesized through synthetic sequences involving as the key step a multicomponent Povarov reaction between an aldehyde, an aniline and an enamine or an enamide as the activated alkene. The novel compounds have been tested against Electrophorus electricus AChE (EeAChE), human recombinant AChE (hAChE), and human serum butyrylcholinesterase (hBChE), and their brain penetration has been assessed using the PAMPA-BBB assay. Also, the mechanism of AChE inhibition of the most potent compounds has been thoroughly studied by kinetic studies, a propidium displacement assay, and molecular modelling. We have found that a seemingly small structural change such as a double O → NH bioisosteric replacement from the hit 1 to 16a results in a dramatic increase of EeAChE and hAChE inhibitory activities (>217- and >154-fold, respectively), and in a notable increase in hBChE inhibitory activity (> 11-fold), as well. An optimized binding at the PAS besides additional interactions with AChE midgorge residues seem to account for the high hAChE inhibitory potency of 16a (IC50 = 65 nM), which emerges as an interesting anti-Alzheimer lead compound with potent dual AChE and BChE inhibitory activities.
Resumo:
The Copper-catalyzed azide-alkyne cycloaddition (CuAAC), often referred to as "click" reaction, has become a very popular reaction in the last years. It affords exclusively 1,4-disubstituted 1,2,3-triazoles and has been widely used to connect readily accessible building blocks containing various functional groups. The great success of this reaction is based on the fact that it is general, virtually quantitative and very robuste. The scope of this copper-catalyzed synthesis is extraordinary and the reaction has found numerous applications in many research fields, including biological chemistry and materials science. In this review, the main chemical aspects and applications of the "click" reaction in the synthesis of 1,2,3-triazoles are presented.
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MeOH extract from the leaves of Plectranthus barbatus Andrews (Lamiaceae), showed in vitro anti-trypanosomal activity. The bioassay-guided fractionation resulted in the isolation of a gallic acid derivative, identified as 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG), after thorough NMR and MS spectral analysis. Finally, this compound was tested against trypomastigote forms of T. cruzi and displayed an EC50 value of 67 µM, at least 6.6-fold more effective than the standard drug benznidazole. This is the first occurrence of PGG in the Plectranthus genus and the first anti-parasitic activity described for PGG in the literature.
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Ruokalista ja ohjelma
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The Co(II), Ni(II) and Cu(II) metal ions complexes of Bis(4-amino-5-mercapto-1,2,4-triazol-3-yl) alkanes (BATs) have been prepared and characterized by elemental analysis, conductivity measurements infrared, magnetic susceptibility, the electronic spectral data and thermal studies. Based on spectral and magnetic results, the ligands are tetradentate coordinating through the N and S-atoms of BATs; six-coordinated octahedral or distorted octahedral and some times four-coordinated square planar were proposed for these complexes. Activation energies computed for the thermal decomposition steps were compared. The ligands and their metal complexes were tested in vitro for their biological effects. Their activities against two gram-positive, two gram-negative bacteria and two fungal species were found to vary from moderate to very strong.
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kuv., 24 x 16 cm
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A atividade de três fármacos antivirais (Aciclovir [ACV], Ganciclovir [GCV] e Foscarnet [PFA]) foi testada in vitro frente aos herpesvírus bovino tipos 1 (BoHV-1), 2 (BoHV-2) e 5 (BoHV-5). Para isso, utilizou-se o teste de reducao de placas virais em cultivo celular, testando-se diferentes concentracoes dos farmacos frente a 100 doses infectantes para 50% dos cultivos celulares (DICC50) dos respectivos virus. Pelo teste de MTT (3-(4,5-Dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide), verificou-se que concentracoes inferiores a 200ƒÊg/mL dos tres antivirais resultaram em indices de viabilidade de celulas MDBK e Hep2 superiores a 80%. Com base na concentracao citotoxica para 50% das celulas (CC50) e na concentracao dos farmacos efetiva para inibir em 50% o numero de placas virais (EC50), calculou-se o indice de seletividade (IS) dos antivirais para os tres herpesvirus. Assim, o ACV demonstrou ser moderadamente ativo frente ao BoHV-1 (EC50: 112,9ƒÊg/mL e IS: 4,5), ao BoHV-2 (EC50: 114,2 ƒÊg/mL e IS: 4,5) e BoHV-5 (EC50: 96,9ƒÊg/mL e IS: 5,3). O GCV apresentou atividade moderada frente ao BoHV-2 (EC50: 33,5ƒÊg/mL e IS: 16,6) e, em menor grau, contra o BoHV-5 (EC50: 123,2ƒÊg/mL e IS: 4,5), sendo ineficaz frente ao BoHV-1 (EC50: 335,8ƒÊg/mL e IS: 1,7). O PFA apresentou atividade antiviral mais pronunciada, sendo o unico farmaco que, na concentracao de 100ƒÊg/mL, inibiu completamente a producao de placas pelos tres virus testados. O PFA foi o mais efetivo in vitro frente ao BoHV-1 (EC50: 29,5ƒÊg/mL e IS: 42,2), ao BoHV-2 (EC50: 45,2ƒÊg/mL e IS: 27,6) e ao BoHV-5 (EC50: 7,8ƒÊg/mL e IS: 160,6). Portanto, os resultados obtidos indicam que o PFA pode se constituir em um candidato para terapia experimental de infeccoes pelos herpesvirus de bovinos in vivo.
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Tämän tutkimuksen aiheena on yhden lapsen kielenkehitys kahden vuoden tarkastelujakson aikana. Tutkimus on aloitettu lapsen ollessa vuoden ja kahdeksan kuukauden (1;8) ikäinen. Kielenkehitystä seurataan ikään kolme vuotta ja kahdeksan kuukautta (3;8). Tutkimusaineisto jakautuu neljään eri tarkastelujaksoon (ikä 1;8–2;0, 2;6–2;7, 3;0–3;1 ja 3;7–3;8). Olen seurannut informanttini kielenkehitystä syntymästä alkaen ja havainnut, että lapsen kielessä voi tapahtua jo hyvin lyhyessäkin ajassa huomattavaa edistymistä. Toisaalta jotkin lapsenkielelle tyypilliset piirteet, kuten ongelmat astevaihtelussa (näkit ’näit’), voivat säilyä vielä pitkäänkin lapsen puheessa. Aineisto koostuu päiväkirjamerkinnöistä ja lapsen puheesta tehdyistä nauhoituksista, jotka on litteroitu. Työn tavoitteena on selvittää, miten lapsen verbit ja lauserakenteet kehittyvät. Lisäksi tuon esiin jokaisena tarkasteltavana ikäkautena joitakin kyseiselle iälle tyypillisiä kielen piirteitä, kuten murteellisuutta ja uudissanoja. Aineistoa analysoidaan sekä kvalitatiivisesti että kvantitatiivisesti. Tutkimus kuuluu lapsenkielen tutkimuksen alaan. Tutkimustulokset osoittavat, että informanttini kielenkehitys noudattelee suomalaislapselle tyypillisiä kehityspolkuja. Informanttini ensimmäisinä omaksumat verbinmuodot esimerkiksi ovat yksikön 2. persoonan imperatiivi (iskä päisty ’väisty’) ja yksikön 3. persoonan indikatiivin preesens (Aada tottaa ’ottaa’). Persoona-, modus- ja tempuskategoriat monipuolistuvat iän karttuessa. Esimerkiksi iässä 2;6 informantti käyttää jo kaikkia muita moduksia paitsi potentiaalia. Iässä 3;0 lapsi on omaksunut kaikki persoonamuodot. Ikään 3;8 mennessä lapsi käyttää myös kaikkia tempuksia. Infinitiivejäkin puheessa esiintyy jo varhain (nykätä ’tykätä’, nukkumassa). Toisaalta variaatio voi olla samanikäistenkin lasten välillä varsin suurta, vaikka kehitys olisi täysin ikäkaudelle ominaista. Siksi jokainen lapsenkielen tutkimus antaa arvokasta tietoa kielenkehityksestä, joka on hyvin yksilöllistä. Tutkimustulokset tuovat esiin monia lapsenkielelle tyypillisiä piirteitä, kuten analogiamuotojen (hakes ’haki’) ja lapsenkielisten sanojen (sylkky ’syli’) esiintymistä puheessa. Toisaalta lapsen puheessa esiintyy alusta asti aikuiskielelle ominaisesti esimerkiksi niin konkreettisia verbejä (mennä, tulla), mentaalisia verbejä (haluta, puhua) kuin sekundaariverbejäkin (voida, täytyä). Toisaalta verbin vaatimat pakolliset täydennykset voivat toisinaan erityisesti tutkittavan ajanjakson alussa olla vielä puutteellisia. Esimerkiksi subjekti saattaa puuttua sitä edellyttävästä lauseesta (peekää tota ’Aada pelkää tuota’). Toisaalta aikuistenkin puhekielelle ovat ominaisia muun muassa yksisanaiset ilmaukset ja verbittömät lauseet. Puhekieli ja alueellinen variaatio tulisikin aina huomioida myös tutkittaessa lapsenkieltä. Nopeasti lapsen lauseet kuitenkin monipuolistuvat ja lauseissa alkaa täydennysten lisäksi esiintyä runsaasti vapaita määritteitä. Lapsen yhdyslauseet ja konjunktioiden käyttö lisääntyvät erityisesti iästä 2;6 alkaen. Lapsen lauserakenteet monipuolistuvat sanaston ja erilaisten verbilekseemien ja verbinmuotojen lisääntyessä.
Resumo:
We determined the effect of long-term aerobic swimming training regimens of different intensities on colonic carcinogenesis in rats. Male Wistar rats (11 weeks old) were given 4 subcutaneous injections (40 mg/kg body weight each) of 1,2-dimethyl-hydrazine (DMH, dissolved in 0.9% NaCl containing 1.5% EDTA, pH 6.5), at 3-day intervals and divided into three exercise groups that swam with 0% body weight (EG1, N = 11), 2% body weight (EG2, N = 11), and 4% body weight of load (EG3, N = 10), 20 min/day, 5 days/week for 35 weeks, and one sedentary control group (CG, N = 10). At sacrifice, the colon was removed and counted for tumors and aberrant crypt foci. Tumor size was measured and intra-abdominal fat was weighed. The mean number of aberrant crypt foci was reduced only for EG2 compared to CG (26.21 ± 2.99 vs 36.40 ± 1.53 crypts; P < 0.05). Tumor incidence was not significantly different among groups (CG: 90%; EG1: 72.7%; EG2: 90%; EG3: 80%). Swimming training did not affect either tumor multiplicity (CG: 2.30 ± 0.58; EG1: 2.09 ± 0.44; EG2: 1.27 ± 0.19; EG3: 1.50 ± 0.48 tumors) or size (CG: 1.78 ± 0.24; EG1: 1.81 ± 0.14; EG2: 1.55 ± 0.21; EG3: 2.17 ± 0.22 cm³). Intra-abdominal fat was not significantly different among groups (CG: 10.54 ± 2.73; EG1: 6.12 ± 1.15; EG2: 7.85 ± 1.24; EG3: 5.11 ± 0.74 g). Aerobic swimming training with 2% body weight of load protected against the DMH-induced preneoplastic colon lesions, but not against tumor development in the rat.
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Invokaatio. I.N.J.
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Invokaatio: I.N.J.
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0-meridiaani : Helsinki.