Home About us Contact
|
Home About us Contact | ||
|
|
||
One Derivatives (one + derivative)
Selected AbstractsSynthesis, Characterization and Electrochemistry of the Novel Dawson-Type Tungstophosphate [H4PW18O62]7, and First Transition Metal Ions DerivativesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 2 2004Israel-Martyr Mbomekalle Abstract Following the synthesis of pure [H4PW18O62]7, (PW18), its derivatives monosubstituted with M (M = MoVI, VIV, VV, MnII, FeIII, CoII, NiII CuII and ZnII) were obtained. All compounds were characterized by elemental analysis, IR, UV/visible and 31P NMR spectroscopy. Their cyclic voltammetry properties were studied as a function of pH and systematically compared with those of their analogs derived from the symmetrical species, [P2W18O62]6,(P2W18). Comparison of the two unsubstituted precursors revealed that the merging of the first two waves of the monophosphate occurred in a less acidic medium than for the diphosphate. The observations point to the higher basicity of the reduced forms of PW18 compared with those of P2W18. The fingerprint pattern observed for ,2 -P2W17M derivatives in media of pH = 3 consisted of the splitting of the third W redox system into two one-electron closely spaced waves which is in contrast to the same system in ,1 -P2W17M. This peculiarity was also obtained for several of the present ,2 -PW17M systems in media of pH = 3 and confirmed that ,2 -substituted derivatives were indeed formed. The absence of this peculiar behavior in some other derivatives is consistent with smooth variations of acid-base properties from one derivative to the next. The electrocatalytic properties of all the compounds are illustrated by the reduction of nitrite by reduced PW18 and of nitrate by reduced ,2 -PW17Cu. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Iron(III) Salt-Catalyzed Nazarov Cyclization/Michael Addition of Pyrrole DerivativesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1-2 2009Masamune Fujiwara Abstract The Nazarov cyclization of two types of pyrrole derivatives was effectively catalyzed by 5,mol% alumina-supported iron(III) perchlorate [Fe(ClO4)3,Al2O3 ] which provided the desired cyclization with high trans selectivity in good to excellent yield. The cyclized product was next reacted with a vinyl ketone in the presence of the same iron salt to afford the corresponding Michael product. A sequential type Nazarov/Michael reaction of pyrrole derivatives has also been accomplished; the synthetic route to 4,5-dihydrocyclopenta[b]pyrrol-6(1,H)-one derivative 5 or 5,6-dihydrocyclopenta[b]pyrrol-4(1,H)-one derivative 6 has thus been established using a very economical iron catalyst. [source] On the Way to Selective PARP-2 Inhibitors.CHEMMEDCHEM, Issue 6 2008Design, Preliminary Evaluation of a Series of Isoquinolinone Derivatives, Synthesis Abstract PARP-1 and PARP-2 are members of the family of poly(ADP-ribose)polymerases, which are involved in the maintenance of genomic integrity under conditions of genotoxic stimuli. The different roles of the two isoforms under pathophysiological conditions have not yet been fully clarified, and this is partially due to the lack of selective inhibitors. We report herein the synthesis and preliminary pharmacological evaluation of a large series of isoquinolinone derivatives as PARP-1/PARP-2 inhibitors. Among them, we identified the 5-benzoyloxyisoquinolin-1(2,H)-one derivative as the most selective PARP-2 inhibitor reported so far, with a PARP-2/PARP-1 selectivity index greater than 60. [source] Highly Enantioselective Hydrogenation of Quinoline and Pyridine Derivatives with Iridium-(P-Phos) CatalystADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2010Wei-Jun Tang Abstract The use of a chiral iridium catalyst generated in situ from the (cyclooctadiene)iridium chloride dimer, [Ir(COD)Cl]2, the P-Phos ligand [4,4,-bis(diphenylphosphino)-2,2,,6,6,-tetramethoxy-3,3,-bipyridine] and iodine (I2) for the asymmetric hydrogenation of 2,6-substituted quinolines and trisubstituted pyridines [2-substituted 7,8-dihydroquinolin-5(6H)-one derivatives] is reported. The catalyst worked efficiently to hydrogenate a series of quinoline derivatives to provide chiral 1,2,3,4-tetrahydroquinolines in high yields and up to 96% ee. The hydrogenation was carried out at high S/C (substrate to catalyst) ratios of 2000,50000, reaching up to 4000,h,1 TOF (turnover frequency) and up to 43000 TON (turnover number). The catalytic activity is found to be additive-controlled. At low catalyst loadings, decreasing the amount of additive I2 was necessary to maintain the good conversion. The same catalyst system could also enantioselectively hydrogenate trisubstituted pyridines, affording the chiral hexahydroquinolinone derivatives in nearly quantitative yields and up to 99% ee. Interestingly, increasing the amount of I2 favored high reactivity and enantioselectivity in this case. The high efficacy and enantioselectivity enable the present catalyst system of high practical potential. [source] A New Approach to Pyrrolocoumarin Derivatives by Palladium-Catalyzed Reactions: Expedient Construction of Polycyclic Lamellarin ScaffoldADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009Lei Chen Abstract A new and efficient protocol for straightforward synthesis of chromeno[3,4- b]pyrrol-4(3H)-one derivatives by palladium-catalyzed sequential coupling/cyclization reactions has been developed. The key strategy relies on creation of pyrrole ring through palladium-catalyzed intramolecular hydroamination of related acetylenic aminocoumarins. The synthetic utility of the obtained chromeno[3,4- b]pyrrol-4(3H)-one product has been demonstrated by the expedient synthesis of polycyclic lamellarin scaffold in four steps. It provides a new entry to synthesis of potentially valuable lamellarin analogues. [source] Highly Regio- and Stereoselective Iodohydroxylation of Non- Heteroatom-Substituted Allenes: An Efficient Synthesis of 4-[3,-Hydroxy-2,-iodoalk-1,(Z)-enyl]-2(5H)-furanone DerivativesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2007Zhenhua Gu Abstract An efficient protocol for the highly regio- and stereoselective synthesis of 4-(3,-hydroxy-2,-iodoalk-1,(Z)-enyl)furan-2(5H)-one derivatives via selective iodohydroxylation of non-heteroatom-substituted allenes, i.e., 4-allenyl-2(5H)furanones, has been developed. The regio- and stereoselectivity of this reaction may be controlled by the electronic and steric effects of the furanone ring. [source] Novel 2-hydrazino-pyrimidin-4(3H)-one derivatives as potential dihydrofolate reductase inhibitorsJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2010Mariam S. Degani Novel substituted 2-hydrazino-pyrimidin-4(3H)-one derivatives were synthesized and examined for their antifolate activity against DHFR from Pneumocystis carinii (pc), Toxoplasma gondii (tg), Mycobacterium avium (ma), and rat liver (rl). A novel, simple, and feasible methodology was developed for the synthesis of the titled compounds. Amongst these, compound 8 6-phenyl-2-(2-(1-(thiophen-2-yl) ethylidene)hydrazinyl) pyrimidin-4(3H)-one exhibited 17.74 ,M activity against pcDHFR. J. Heterocyclic Chem., (2010). [source] Extension of a cascade reaction: Microwave-assisted synthesis of the GFP chromophore derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2010Runhong Jia A facile microwave-assisted synthesis of imidazol-5(4H)-one derivatives is accomplished via reactions of 4-arylmethylene-2-phenyloxazol-5(4H)-ones with urea (or ammonium acetate) in ethylene glycol. The cascade reaction is simple to perform and occurs under mild conditions with broad scope of applicability. J. Heterocyclic Chem., (2010). [source] A facile synthesis of furo[3,4- e]pyrazolo[3,4- b]pyridine-5(7H)-one derivatives via three-component reaction in ionic liquid without any catalystJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2009Da-Qing Shi A series of furo[3,4- e]pyrazolo[3,4- b]pyridine-5(7H)-one and indeno[2,1- e]pyrazolo[3,4- b]pyridine-5(1H)-one derivatives were synthesized via the three-component reaction of an aldehyde, 5-aminopyrazole and either tetronic acid or 1,3-indanedione in ionic liquid without any catalyst. The structures of the products have been established by spectroscopic data and further confirmed by X-ray diffraction analysis. This method has the advantages of easier work-up, mild reaction conditions, high yields and an environmentally benign procedure. J. Heterocyclic Chem., 46, 469 (2009). [source] Synthesis of 2,6-diamino-5-[(2-substituted phenylamino)ethyl]pyrimidin-4(3h)-one as inhibitors of folate metabolizing enzymes,,JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2006Aleem Gangjee A series of eleven novel 2,6-diamino-5-[(2-substituted phenylamino)ethyl]pyrimidin-4(3H)-one derivatives were synthesized as potential inhibitors of dihydrofolate reductase (DHFR) and thymidylate synthase (TS). The synthesis of analogues 2a-f, 3a and 3e was achieved via an improved method. Commercially available anilines 12a-f were used as starting materials which on reaction with chloroacetaldehyde followed by cyanoacetate and cyclocondensation with guanidine afforded 2,6-diamino-5-[(2-substituted phenylamino)ethyl]pyrimidin-4(3H)-one 2a-f in three steps. The N-methyl analogues 3a-3e were prepared by reductive methylation. These compounds were evaluated against dihydrofolate reductase from Escherichia coli, Toxoplasma gondii, Pneumocystis carinii, human, and rat liver. Few compounds were marginally active against dihydrofolate reductase. The most potent inhibitor, (2c) which has a 1-naphthyl substituent on the side chain, has an IC50 = 150 ,M and 9.1 ,M against Escherichia coli and Toxoplasma gondii DHFR, respectively. [source] Synthesis and further studies of chemical transformation of the 2-aryl-3-halogenoquinolin-4(1H)-one derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2006Malose J. Mphahlele The C-3 brominated and iodinated derivatives were prepared from the corresponding 2-arylquinolin-4(1H)-ones and their NMe-4-oxo derivatives using pyridinium tribromide in acetic acid or iodine-Na2CO3 mixture in THF. The results of further studies of chemical transformation of the prepared ,-haloenones and preliminary antitumour activity of the 3-bromo NH-4-oxo and NMe-4-oxo derivatives are also described. [source] A new regioselective synthesis and bioactivity of 1H -pyrazolo[3,4- d]pyrimidin-4(5H)-one derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 3 2004Hong-Qing Wang A series of new 1H -pyrazolo[3,4- d]pyrimidin-4(5H)-one Derivatives 5 has been designed and regio-selectively synthesized via a tandem aza-Wittig reaction. The structures of all compounds prepared have been confirmed by 1H NMR, IR, EI-MS spectroscopy and elemental analyses. The results of preliminary bioassay indicate that most compounds 5 possess an inhibition effect against Botrytis cinereapers and Pyricularia oryzae at the concentration of 50 mg/L. [source] A new biginelli reaction procedure using potassium hydrogen sulfate as the promoter for an efficient synthesis of 3,4-dihydropyrimidin-2(1H)-oneJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2004Shujiang Tu Simple and improved conditions have been found to carry out the Biginelli reaction for the synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives. This synthesis was performed using potassium hydrogen sulfate as the promoter in ethylene glycol solution. Compared with the classical Biginelli reaction conditions, this new method has the advantage of excellent yields (85,95%) and short reaction time (0.5,2 h). [source] Utilisation of electrospray time-of-flight mass spectrometry for solving complex fragmentation patterns: application to benzoxazinone derivativesJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 10 2003L. S. Bonnington Abstract In this paper we describe the application of electrospray time-of-flight mass spectrometry (ESI-TOFMS) to structural elucidation of the fragment ions formed from a range of natural and synthetic allelochemical derivatives. The extensive mass spectrometric characterisation of ten non-glucosylated benzoxazinone derivatives using this method is described here for the first time. The analytes include six naturally occurring 1,4-benzoxazin-3(4H)-one derivatives, including the hydroxamic acids DIMBOA [2,4-dihydroxy-7-methoxy-2H -1,4-benzoxazin-3(4H)-one] and DIBOA [2,4-dihydroxy-2H -1,4-benzoxazin-3(4H)-one], lactams HBOA [2-hydroxy-2H -1,4-benzoxazin-3(4H)-one] and HMBOA [2-hydroxy-7-methoxy-2H -1,4-benzoxazin-3(4H)-one], benzoxazolinones BOA [benzoxazolin-2(3H)-one] and MBOA [6-methoxy-benzoxazolin-2(3H)-one] and four synthetic variations, 2,H-DIBOA [4-hydroxy-2H -1,4-benzoxazin-3(4H)-one], 2,OMe-DIBOA [2-methoxy-4-hydroxy-2H -1,4-benzoxazin-3(4H)-one], 2,H-HBOA [2H -1,4-benzoxazin-3(4H)-one] and 2,OMe-HBOA [2-methoxy-2H -1,4-benzoxazin-3(4H)-one]. Assignments of the mass spectral fragments were aided by elemental composition calculation results, comparison of structural analogues and background literature, and acquired knowledge regarding feasible structures for the compounds. The influence of substituents on the chemical reactivity of the compounds with respect to the observed MS behaviour over varying nozzle potentials is addressed and, through comparison of the structural analogues, generic fragmentation patterns have also been identified. Copyright © 2003 John Wiley & Sons, Ltd. [source] Seven 3-methylidene-1H -indol-2(3H)-ones related to the multiple-receptor tyrosine kinase inhibitor sunitinibACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2010John Spencer The solid-state structures of a series of seven substituted 3-methylidene-1H -indol-2(3H)-one derivatives have been determined by single-crystal X-ray diffraction and are compared in detail. Six of the structures {(3Z)-3-(1H -pyrrol-2-ylmethylidene)-1H -indol-2(3H)-one, C13H10N2O, (2a); (3Z)-3-(2-thienylmethylidene)-1H -indol-2(3H)-one, C13H9NOS, (2b); (3E)-3-(2-furylmethylidene)-1H -indol-2(3H)-one monohydrate, C13H9NO2·H2O, (3a); 3-(1-methylethylidene)-1H -indol-2(3H)-one, C11H11NO, (4a); 3-cyclohexylidene-1H -indol-2(3H)-one, C14H15NO, (4c); and spiro[1,3-dioxane-2,3,-indolin]-2,-one, C11H11NO3, (5)} display, as expected, intermolecular hydrogen bonding (N,H...O=C) between the 1H -indol-2(3H)-one units. However, methyl 3-(1-methylethylidene)-2-oxo-2,3-dihydro-1H -indole-1-carboxylate, C13H13NO3, (4b), a carbamate analogue of (4a) lacking an N,H bond, displays no intermolecular hydrogen bonding. The structure of (4a) contains three molecules in the asymmetric unit, while (4b) and (4c) both contain two independent molecules. [source] Synthesis of New 2,3-Dihydroquinazolin-4(1H)-one Derivatives for Analgesic and Anti-inflammatory EvaluationARCHIV DER PHARMAZIE, Issue 5 2010Osama I. El-Sabbagh Abstract Starting from isatoic anhydrides, several new 2,3-dihydroquinazolin-4(1H)-one derivatives bearing chalcone or pyrazole or thiazole moieties at the third position were synthesized. The analgesic and anti-inflammatory activities for most compounds were studied at a dose level of 50 mg/kg via the acetic-acid-induced writhing-response method and carrageenan-induced edema method, respectively. The study showed that the chalcones bearing a 4-chlorophenyl group 4c or 4-nitrophenyl group 4b were the most active ones as analgesics. Both chalcone 4c and N -phenyl pyrazole bearing 4-methoxy phenyl group 5b showed a higher anti-inflammatory activity than celecoxib but still lower than that of diclofenac sodium. Moreover, the chalcone 4c has nearly the same ulcerogenic index as the selective cyclooxygenase-2 inhibitor celecoxib. [source] | |||||||||||||||||||||||||