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Propanoic Acid (propanoic + acid)
Selected AbstractsFully quantum mechanical energy optimization for protein,ligand structureJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 12 2004Yun Xiang Abstract We present a quantum mechanical approach to study protein,ligand binding structure with application to a Adipocyte lipid-binding protein complexed with Propanoic Acid. The present approach employs a recently develop molecular fractionation with a conjugate caps (MFCC) method to compute protein,ligand interaction energy and performs energy optimization using the quasi-Newton method. The MFCC method enables us to compute fully quantum mechanical ab initio protein,ligand interaction energy and its gradients that are used in energy minimization. This quantum optimization approach is applied to study the Adipocyte lipid-binding protein complexed with Propanoic Acid system, a complex system consisting of a 2057-atom protein and a 10-atom ligand. The MFCC calculation is carried out at the Hartree,Fock level with a 3-21G basis set. The quantum optimized structure of this complex is in good agreement with the experimental crystal structure. The quantum energy calculation is implemented in a parallel program that dramatically speeds up the MFCC calculation for the protein,ligand system. Similarly good agreement between MFCC optimized structure and the experimental structure is also obtained for the streptavidin,biotin complex. Due to heavy computational cost, the quantum energy minimization is carried out in a six-dimensional space that corresponds to the rigid-body protein,ligand interaction. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1431,1437, 2004 [source] Coordination Chemistry of 3-Mercapto-2-(mercaptomethyl)propanoic Acid (Dihydroasparagusic Acid) with Iron and NickelEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 23 2006Phillip I. Volkers Abstract The first transition-metal complexes bearing the natural product dihydroasparagusic acid, (HSCH2)2CHCO2H, as a ligand are reported. Various coordination modes and nuclearities are demonstrated for the chelating ligand by a series of iron and nickel complexes. Fe2[(SCH2)2CHCO2H](CO)6 retains carbonyl substitution reactivity typical of Fe2(SR)2(CO)6 complexes, yet carboxy coordination to FeI was unobserved. Coupling of the carboxylic acid with amines yields the corresponding amides Fe2[(SCH2)2CHC(O)NHR](CO)6 (R = Et, gly,O,tBu). Fe2[(SCH2)2CHCO2H](CO)4(PMe3)2 catalyzes H2 production, but no better than unfunctionalized alkyl dithiolate analogs. Reactions of the ligand with NiCl2(dppe) afforded mono-, di-, and trinuclear complexes. Noteworthy is Ni3[(SCH2)2CHCO2]2(dppe)2, which features an octahedrally coordinated NiII center linked to a pair of square-planar NiII centers. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] ChemInform Abstract: A One-Pot Synthesis of Novel Functionalized (E)-,-Arylvinyl Bromides from anti-2,3-Dibromo-3-(4-carboxyphenyl)propanoic Acid.CHEMINFORM, Issue 42 2008Chunxiang Kuang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Synthesis of Base Substituted 2-Hydroxy-3-(purin-9-yl)propanoic Acids and 4-(Purin-9-yl)-3-butenoic Acids.CHEMINFORM, Issue 16 2004Petra Dolakova Abstract For Abstract see ChemInform Abstract in Full Text. [source] Naproxen in heterocyclic chemistry: Novel syntheses of triazoles, triazolothiadiazines, triazolothiadiazoles, and triazolothiadiazepine bearing an asymmetric carbon atom and radiostability of the biologically active compoundsHETEROATOM CHEMISTRY, Issue 3 2002Y. A. Ammar Several s-triazoles 2, 7a, 10, 12; s-triazolo[3,4-b][1,3,4]thiadiazines (3,5); s-triazolo[3,4-b][1,3,4]thiadiazoles (6, 8, 11, 15); and s-triazolo[3,4-b][1,3,4]thiadiazepine (14) were synthesized starting from 2-(6-methoxy-2-naphthyl)propanoic acid (1) (Naproxen). The structures of the synthesized compounds were elucidated by elemental analyses and spectral data. Compounds 2, 5, 11, 12, 14, and 15 exhibited a remarkable antifungal activity compared with the standard fungicide Mycostatine. Radiosterilization of the biologically active compounds 2, 5, 11, and 14 in the dry state may prove to be applicable (retaining their structures unchanged up to 40 kGy). © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:199,206, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10019 [source] Synthesis of (2E)-2-methyl-3-(4-{[4-(quinolin-2-ylmethoxy)phenyl]sulfanyl}phenyl)prop-2-enoic acid (VUFB 20609) and 2-methyl-3-(4-{[4-(quinolin-2-ylmethoxy)phenyl]sulfanyl}phenyl)propanoic acid (VUFB 20584) as potential antileukotrienic agentsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 6 2004J. Jampílek The Synthesis of (2E)-2-methyl-3-(4-{[4-(quinolin-2-ylmethoxy)phenyl]sulfanyl}phenyl) prop-2-enoic acid (VUFB 20609) and racemic 2-methyl-3-(4-{[4-(quinolin-2-ylmethoxy) phenyl]sulfanyl}phenyl)propanoic acid (VUFB 20584) as new potential antileukotrienic drugs are described. Due to a low reactivity of the 4-substituted aryl bromides (coupling of the 4-substituted aryl bromides do not provide an activating functional group with 4-methoxybenzene-1-thiol), special conditions, in particular specific heterogeneous copper catalysts, were used. Catalytic hydrogenation of the conjugated double bond on Pd/C in the presence of the sulfanyl group is discussed. In-vitro cytotoxicity testing was performed using a microplate colorimetric acid phosphatase assay. Antiplatelet activity was evaluated using an in-vitro test in human platelet-rich plasma. Some substances inhibited arachidonic acid-induced platelet aggregation. [source] Photochemical behaviour of dichlorprop [(±)-2-(2,4-dichlorophenoxy)propanoic acid] in aqueous solutionPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 8 2002Laurence Meunier Abstract Aqueous solutions of dichlorprop were irradiated under different conditions of pH, wavelength and oxygenation. The photochemical behaviour was found to be complex and many photoproducts were formed. However, at low concentrations the main photoproducts were 4-chloropyrocatechol, 2-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol. Some other photoproducts were identified, namely 2-(4-chloro-2-hydroxyphenoxy)propanoic acid, 2-(3,5-dichloro-2-hydroxyphenyl)propanoic acid and 2,4-dichlorophenyl acetate. From comparison with results previously obtained with mecoprop [2-(4-chloro-2-methylphenoxy)propanoic acid] it appears that the presence of a chlorine atom in position 2 on the ring strongly modifies the photochemical behaviour. © 2002 Society of Chemical Industry [source] Pseudomonas putida KT2440 responds specifically to chlorophenoxy herbicides and their initial metabolitesPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 11 2006Dirk Benndorf Dr. Abstract Pseudomonas putida,KT2440 is often used as a model to investigate toxicity mechanisms and adaptation to hazardous chemicals in bacteria. The objective of this paper was to test the impact of the chlorophenoxy herbicides 2,4-dichlorophenoxyacetic acid,(2,4-D) and 2-(2,4-dichlorophenoxy)propanoic acid,(DCPP) and their metabolites 2,4-dichlorophenol,(DCP) and 3,5-dichlorocatechol,(DCC), on protein expression patterns and physiological parameters. Both approaches showed that DCC has a different mode of action and induces different responses than DCPP, 2,4-D and DCP. DCC was the most toxic compound and was active as an uncoupler of oxidative phosphorylation. It repressed the synthesis of ferric uptake regulator (Fur)-dependent proteins, e.g. fumarase,C and L -ornithine N5-oxygenase, which are involved in oxidative stress response and iron uptake. DCPP, 2,4-D and DCP were less toxic than DCC. They disturbed oxidative phosphorylation to a lesser extent by a yet unknown mechanism. Furthermore, they repressed enzymes of energy-consuming biosynthetic pathways and induced membrane transporters for organic substrates. A TolC homologue component of multidrug resistance transporters was found to be induced, which is probably involved in the removal of lipophilic compounds from membranes. [source] (S,S)-Lactoyllactic acid and (S,S,S)-lactoyllactoyllactic acidACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2010Martin Lutz The dimeric condensation product of lactic acid, namely (S,S)-2-[(2-hydroxypropanoyl)oxy]propanoic acid, C6H10O5, (I), crystallizes with two independent molecules in the asymmetric unit, which both have an essentially planar backbone. The trimeric condensation product, namely (S,S,S)-3-hydroxybut-3-en-2-yl 2-[(2-hydroxypropanoyl)oxy]propanoate, C9H14O7, (II), has one molecule in the asymmetric unit and consists of two essentially planar parts, with the central C,O bond in a gauche conformation. Both molecules of the dimer are involved in intermolecular hydrogen bonds, forming chains with a C(8) graph set. These chains are connected by D(2) hydrogen bonds to form a two-dimensional layer. The trimer forms hydrogen-bonded C(10) and C22(6) chains, which together result in a two-dimensional motif. The Hooft method [Hooft, Straver & Spek (2008). J. Appl. Cryst. 41, 96,103] was successfully applied to the determination of the absolute structure of (I). [source] 3-[1-(4-Sulfamoylphenyl)-5- p -tolyl-1H -pyrazol-3-yl]propanoic acid and 3-[5-(4-bromophenyl)-1-(4-sulfamoylphenyl)-1H -pyrazol-3-yl]propanoic acid,dichloromethane,diethyl ether,water (2/0.72/1/1)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 6 2009Isuru R. Kumarasinghe The syntheses of 3-[1-(4-sulfamoylphenyl)-5- p -tolyl-1H -pyrazol-3-yl]propanoic acid, C19H19N3O4S, (I), and 3-[5-(4-bromophenyl)-1-(4-sulfamoylphenyl)-1H -pyrazol-3-yl]propanoic acid,dichloromethane,diethyl ether,water (2/0.72/1/1), 2C18H16BrN3O4S·0.72CH2Cl2·C4H10O·H2O, (II), are regiospecific. However, correct identification by spectroscopic techniques of the regioisomer formed is not trivial and single-crystal X-ray analysis provided the only means of unambiguous structure determination. Both structures make extensive use of hydrogen bonding and while compound (I) forms a straightforward unsolvated Z, = 1 structure, compound (II) crystallizes as an unusual mixed solvate, with two crystallographically unique molecules of the pyrazole derivative present in the asymmetric unit. The structure of (II) also features Br...Br interactions. [source] Adaptability and selectivity of human peroxisome proliferator-activated receptor (PPAR) pan agonists revealed from crystal structuresACTA CRYSTALLOGRAPHICA SECTION D, Issue 8 2009Takuji Oyama Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone receptor family, which is defined as transcriptional factors that are activated by the binding of ligands to their ligand-binding domains (LBDs). Although the three PPAR subtypes display different tissue distribution patterns and distinct pharmacological profiles, they all are essentially related to fatty-acid and glucose metabolism. Since the PPARs share similar three-dimensional structures within the LBDs, synthetic ligands which simultaneously activate two or all of the PPARs could be potent candidates in terms of drugs for the treatment of abnormal metabolic homeostasis. The structures of several PPAR LBDs were determined in complex with synthetic ligands, derivatives of 3-(4-alkoxyphenyl)propanoic acid, which exhibit unique agonistic activities. The PPAR, and PPAR, LBDs were complexed with the same pan agonist, TIPP-703, which activates all three PPARs and their crystal structures were determined. The two LBD,ligand complex structures revealed how the pan agonist is adapted to the similar, but significantly different, ligand-binding pockets of the PPARs. The structures of the PPAR, LBD in complex with an ,/,-selective ligand, TIPP-401, and with a related ,-specific ligand, TIPP-204, were also determined. The comparison between the two PPAR, complexes revealed how each ligand exhibits either a `dual selective' or `single specific' binding mode. [source] Absolute configurations of chiral herbicides determined from vibrational circular dichroismCHIRALITY, Issue S1 2005Jiangtao He Abstract Enantiopure herbicides (+)-2-(4-chloro-2-methylphenoxy) propanoic acid, (+)- 1 and (+)-2-(2,4-dichlorophenoxy) propanoic acid, (+)- 2 were investigated using vibrational circular dichroism (VCD). Experimental absorption and VCD spectra of (+)- 1 and (+)- 2 in CDCl3 solution in the 2000,900 cm,1 region were compared with the ab initio predictions of absorption and VCD spectra obtained with density functional theory using the B3LYP/6-31G* basis set for different conformers of (R)- 1 and (R)- 2. Due to the intermolecular hydrogen bonding, this comparison did not provide unambiguous conclusions. To eliminate intermolecular hydrogen bonding influence, the two acids 1 and 2 were converted to the corresponding methyl esters, namely, (+)-methyl 2-(4-chloro-2-methylphenoxy) propanoate, (+)- 3 and (+)-methyl 2-(2,4-dichlorophenoxy) propanoate, (+)- 4. The experimental VCD spectra were measured for these esters and ab initio calculations for different conformers of (R)- 3 and (R)- 4 were carried out. The experimental VCD spectra and corresponding population-weighted theoretical VCD spectra were found to be in excellent agreement, which allowed unambiguous determination of absolute configuration of 3 and 4 as (+)-(R). Since esterification does not invert the configuration, the absolute configuration of the parent acids 1 and 2 is the same as that of corresponding methyl esters. Chirality 17:S1,S8, 2005. © 2004 Wiley-Liss, Inc. [source] | |||||||||||||||||||