22 research outputs found
Antiproliferativna aktivnost glutarimidnih derivata iz baze podataka Nacionalnog instituta za rak, SAD - 3D odnos strukture i aktivnosti nezavisan od poravnavanja molekula
Alignment-free, three dimensional structure-activity relationships (3D QSAR) of the antiproliferative potency of twenty-two glutarimide-containing compounds, taken from National Cancer Institute Developmental therapeutics Program database, toward eight representative human tumour cell lines are reported. The descriptors used in the QSAR study were derived from GRID molecular interaction fields. The obtained models readily detect structural motifs positively or negatively correlated with the potency of the studied compounds toward each cell line. In this way, the pharmacophoric pattern required for high potency of compounds is reported. This pattern can serve as guidance for the design and syntheses of novel congeners, planned to be tested toward human tumour cell lines.U tekstu je opisan odnos strukture i antiproliferativne aktivnosti 22 glutarimidna derivata prema osam reprezentativnih linija humanih tumora. Podaci o strukturi jedinjenja i njihovoj aktivnosti su preuzeti iz baze podataka Nacionalnog Instituta za rak, SAD. Deskriptori, nezavisni od poravnavanja molekula (GRIND-2), korišćeni u proučavanju odnosa strukture i aktivnosti su dobijeni upotrebom programa GRID. Modeli jasno prikazuju strukturne elemente jedinjenja koji se pozitivno ili negativno korelišu sa biološkom aktivnošću. Farmakoforna slika dobijena iz modela će biti korišćena za planiranje novih analoga koji sadrže glutarimidni prsten i za koje se očekuje da će pokazati značajnu antiproliferativnu aktivnost
Redox properties of alkyl-substituted 4-aryl-2,4-dioxobutanoic acids
© 2017 J. Serb. Chem. Soc. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (https://creativecommons.org/licenses/by-nc-nd/4.0/).Redox properties of a set of aryldiketo acids (ADKs), small organic molecules that comprise 2,4-dioxobutanoic acid moiety, were studied. Along with well-known HIV-1 integrase (IN) inhibition, ADKs exert widespread biological activities. The aim of this work was to evaluate effects of aryl substitutions on properties of dioxobutanoic moiety that is involved in key interactions with metal ions within active sites of target enzymes. The effect of pH on electronic properties of nine congeners was examined using cyclic voltammetry and differential pulse polarography. Compounds were chosen as a simple set of congeners, bearing Me-groups on phenyl ring which should not be involved in electrochemical reactions, leaving diketo moiety as sole electrophore. Substitution pattern was systematically varied, yielding a set having different torsion between phenyl ring and aryl keto group (Ar-C(O)). Protonation state of ADKs at different pH values was determined from experimentally obtained pKas. The results showed that the equal number of protons and electrons is involved in the oxidation and reduction reactions at the surface of electrode. Quantitative linear correlations between reduction potentials and energies of frontier orbitals, calculated for neutral, monoanionic and corresponding radical anionic species, and steric parameter were found.Peer reviewe
Different levels of humoral immunoreactivity to different wheat cultivars gliadin are present in patients with celiac disease and in patients with multiple myeloma
<p>Abstract</p> <p>Background</p> <p>Immunity to food antigens (gliadin, cow's milk proteins) is in the centre of the attention of modern medicine focused on the prevention of diseases, prevention which is based on the use of appropriate restriction diet. Detection of the enhanced levels of the immune reactions to antigen(s) present in food is from this point of view of great importance because there are reports that some of health disturbances, like celiac disease (CD) and some premalignant conditions, like monoclonal gammopathy of undetermined significance (MGUS), were vanished after the appropriate restriction diets.</p> <p>It is well known that gliadin is toxic to small bowel mucosa of relatively small population of genetically predisposed individuals, who under this toxic action develop celiac disease (CD). As the quantity of immunogenic gliadin could vary between different wheat species, the first aim of this work was to determine the percentage of immunogenic gliadin in ten bread wheat cultivars and in three commercially grown durum wheat cultivars. The second part of the study was initiated by results of previous publication, reporting that sera of some of multiple myeloma (MM) patients showed the presence of elevated levels of anti-gliadin IgA, without the enhanced levels of anti-gliadin IgG antibodies, determined with commercial ELISA test. It was designed to assess is it possible to reveal is there any hidden, especially anti-gliadin IgG immunoreactivity, in serum of mentioned group of patients. For this purpose we tested MM patients sera, as well as celiac disease (CD) patients sera for the immunoreaction with the native gliadin isolated from wheat species used for bread and pasta making in corresponding geographic region.</p> <p>Results</p> <p>Gliadin was isolated from wheat flour by two step 60% ehanolic extraction. Its content was determined by commercial R5 Mendez Elisa using PWG gliadin as the standard. Results obtained showed that immunogenic gliadin content varies between 50.4 and 65.4 mg/g in bread wheat cultivars and between 20 and 25.6 mg/g in durum wheat cultivars.</p> <p>Anti-gliadin IgA and IgG immunoreactivity of patients' sera in (IU/ml) was firstly determined by commercial diagnostic Binding Site ELISA test, and then additionally by non-commercial ELISA tests, using standardized ethanol wheat extracts -gliadin as the antigen.</p> <p>In both patients groups IgA immunoreactivity to gliadin from different cultivars was almost homogenous and in correlation with results from commercial test (except for one patient with IgA(λ) myeloma, they were more then five times higher). But, results for IgG immunoreactivity were more frequently inhomogeneous, and especially for few MM patients, they were more then five times higher and did not correlate with results obtained using Binding Site test.</p> <p>Conclusion</p> <p>Results obtained showed different content of immunogenic gliadin epitopes in various species of wheat.</p> <p>They also point for new effort to elucidate is there a need to develop new standard antigen, the representative mixture of gliadin isolated from local wheat species used for bread production in corresponding geographic region for ELISA diagnostic tests.</p
Molecular-orbital and structural descriptors in theoretical investigation of electroreduction of nitrodiazoles
It is shown how a simple theoretical approach can be used for the investigation of electro-organic reactions.Mononitroimidazoles and mononitropyrazoles were studied by the semiempirical MNDO-PM3 molecular orbital method. The electrochemical reduction potentials of diazoles have been correlated with the energy of the lowest unoccupied molecular orbital (LUMO). It was found that an admirable correlation could be obtained by the introduction of simple structural descriptors as a correction to the energy of the LUMO. The interaction of a molecule with its surrounding depends on electrostatic potential and on steric hindrance. Most of these steric effects are taken into account using two parameters having a very limited set of integer values. The first (b) is the position of a ring substituent regarding ring nitrogens, which accounts for the different orientations of dipole moments and for the different shape of the electrostatic potential. The second (structural) parameter (t) is the type of the ring, which accounts mostly for different modes of electrode approach, and for different charge polarization patterns in two diazole rings. The extended correlation with ELUMO, b and t, is very good, having a regression coefficient r = 0.991. The intrinsic importance of b and t is exemplified by their high statistical weight
Pressure Dependence Of The Photooxidation Of Selected Carbonyl Compounds In Air: N-Butanal And N-Pentanal
Dilute mixtures of n-butanal and n-pentanal in synthetic air (up to 100 ppm) were photolyzed with fluorescent UV lamps (275--380 nm) in air at 298 K. The main photooxidation products, identified and quantitatively analyzed by FT-IR spectroscopy, were ethene (n-butanal) or propene (n-pentanal), CO, vinylalcohol and ethanal. The photolysis rates and the absolute quantum yields # of both compounds were found to be slightly dependent on the total pressure. At 100 Torr, in the photolysis of n-butanal and n-pentanal # 100 0.02 and 0.40 0.04, whereas at 700 Torr, the total quantum yields were # 700 0.38 0.02 and 0.32 0.01, respectively. These results could be explained by the collisional deactivation of photoexcited molecules. Two decomposition channels were identified in both cases: the radical channel RCHO R HCO, and the molecular channel C x H y CHO C x-1 H y-3 CH 2 =CHOH, having the relative yields of 68 3% (n-butanal), and 20 4% (n-pentanal) at 700 Torr. The product, CH 2 =CHOH, tautomerizes to ethanal. UV absorption cross-sections were measured prior to photolysis. For the comparison, the products were also analyzed after photolysis of both compounds in teflon bags using direct sunlight. 2001 Elsevier Science B.V. All rights reserved
Docking Studies and Anti-inflammatory Activity of β-Hydroxy-β-arylpropanoic Acids
The article describes a two-step synthesis of diastereomeric 3-hydroxy-2-methyl-3-(4-biphenylyl)butanoic acids. In the first step an intermediate α-bromo propanoicacid 1-ethoxyethyl ester was synthesized. The second step is a new modified Reformatskyreaction in presence of Zn in tetrahydrofuran (THF) at –5 to 10 °C between the previouslysynthesized intermediate and 4-acetylbiphenyl. Synthesis of the other studied β-hydroxy-β-arylpropanoic acids has already been reported. These β-hydroxy-β-arylpropanoic acidsbelong to the arylpropanoic acid class of compounds, structurally similar to the NSAIDssuch as ibuprofen. The anti-inflammatory activity and gastric tolerability of thesynthesized compounds were evaluated. Molecular docking experiments were carried outto identify potential COX-2 inhibitors among the β-hydroxy-β-aryl-alkanoic acids class.The results indicate that all compounds possess significant anti-inflammatory activity afteroral administration and that the compounds 2-(9-(9-hydroxy-fluorenyl))-2-methylpropanoic acid (5) and 3-hydroxy-3,3-diphenyl-propanoic acid (3) possess thestrongest anti-inflammatory activity, comparable to that of ibuprofen, a standard NSAID,and that none of tested substances or ibuprofen produced any significant gastric lesions
Molecular orbital study of the oxidation of steroidal phenols into quinols and epoxyquinols
The MO study showed that the radical oxidation of phenols into quinols occurs readily. Further radical oxidation (in the m-CPBA / (BzO)2 /hn system) of quinols occurs through appropriate biradical species with an activation energy of 79.5 kJ/mol yielding syn-epoxyquinols. The stereochemical outcome presented in this study is in full agreement with the experimental results