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Synthesized Compounds (synthesized + compound)
Selected AbstractsStructure,Activity Relationship in the Domain of Odorants Having Marine NotesHELVETICA CHIMICA ACTA, Issue 7 2007Jean-Marc Gaudin Abstract We synthesized or re-synthesized a large series of 2H -1,5-benzodioxepin-3(4H)-ones 9 (Scheme,1), 4,5-dihydro-1-benzoxepin-3(2H)-ones 10 (Schemes 3 and 4) and 5,6,8,9-tetrahydro-7H -benzocyclohepten-7-ones 11 (Schemes 5 and 6), since the lead compound for the olfactory note of perfumes based on marine accords is a well-known benzodioxepinone named Calone 1951® (9b). We meticulously described the odor profile of each synthesized compound and discussed relevant structure,odor relationships (Tables,1,3). In particular, we revealed a correlation between the conformation of the seven-membered ring and the activities of these compounds (Table,4 and Fig.,3). We also clarified the effect of the position and the size of the alkyl substituent at the aromatic ring. [source] Supramolecular Nanocycles Comprising , -Cyclodextrin-click-Ferrocene Units: Rings of Rings of RingsMACROMOLECULAR RAPID COMMUNICATIONS, Issue 7 2010Maricica Munteanu Abstract We applied 1,3-dipolar cycloaddition to bind ethynylferrocene onto 6I-azido-6I-deoxycyclomaltoheptaose under microwave assisted conditions. The process was investigated by 1H NMR, FT-IR spectroscopy, and MALDI-TOF mass spectrometry. The ability of the synthesized compound to self-organize to cyclic supramolecular structures was investigated by dynamic light scattering measurements and cryo-transmission electron microscopy. [source] Neutral and Cationic Methylaluminium Complexes of 2-Anilinotropone Ligands: Synthesis, Characterization, and Reactivity toward EthyleneEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 6 2004Daniela Pappalardo Abstract Some new aluminium complexes bearing bidentate monoanionic 2-anilinotroponate ligands have been synthesized and characterized. Reaction of 2-(2,6-diisopropylanilino)tropone or 2-(perfluoroanilino)tropone with AlMe3 (1 equiv.) gave, by methane elimination, compounds [2-(2,6-diisopropylanilino)tropone]AlMe2 (1) and [2-(perfluoroanilino)tropone]AlMe2 (2), respectively, as yellow solids. Reaction of 1 with 1 equiv. of the ligand furnished, by protodealumination of a second Al,CH3 bond, the [2-(2,6-diisopropylanilino)tropone]2AlMe derivative 3. The structure of 3 has been determined by single-crystal X-ray diffraction, showing a five-coordinate aluminium atom with a distorted trigonal-bipyramidal geometry. Compounds 1 and 3 underwent methyl abstraction reactions with B(C6F5)3; the resulting cationic species was trapped in the presence of THF in dichloromethane solution. The reactivity of the synthesized compounds in ethylene polymerisation has also been explored. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Study of the Reaction of 3-Formylrifamycin SV with Gaseous Ammonia and Acetone,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 18 2006Krzysztof Bujnowski Abstract In the second stage of our study concerning the search for new antibacterial rifamycin antibiotics, reaction of the aldehydes 3-formylrifamycin SV (1) and 25- O -deacetyl-3-formylrifamycin SV with ammonia and acetone has been investigated. A new synthetic method for the preparation of a new group of rifamycin derivatives with a cyclic substituent at C-3 having a 4-piperidone structure, represented by compounds 6a, 6b, and 7a, has been developed. The structures of the compounds and a reaction mechanism have been proposed on the basis of mass spectrometry results as well as 1D and 2D 1H and 13C NMR analysis. The results of the in vitro tests confirm the antituberculous activity of the synthesized compounds. Furthermore, 6a, which is isolated in good yield, is a promising substrate for a new class of rifamycin derivatives. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Olfactory properties of straight-chain undecan -x- ones, undecan -x- ols (x = 2,6) and their derivativesFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2008Julia Gibka Abstract A series of undecan -x- ones (x = 2,6) was used as starting material in the synthesis of ethylene and propylene acetals, undecanols and their acetates. Undec-3-yl and undec-6-yl acetates, ethylene acetal of undecan-3-one and propylene acetals of undecan -x- ones (x = 2,5) have not yet been described. The odour properties for all the synthesized compounds have been determined. They have pleasant, fruity, herbaceous odours that can be described as food odours. The most valuable groups of compounds are ketones and their acetals, which have intense, pleasant, fruity, vegetable, spicy or herbaceous odours. In the case of alcohols, mild odours dominate with fruity, wooden or floral notes. All acetates have faint or mild fatty-soapy odours. A correlation between the structure of the studied compounds and their odours has been found. Fruity odours appear among ketones and alcohols when a shift of the functional group from position 2 to the middle of the molecule occurs. In the studied ethylene and propylene acetals this shift strengthens their vegetable and spicy odours, respectively. Copyright © 2008 John Wiley & Sons, Ltd. [source] Luminescent Soft Material: Two New Europium-Based Ionic LiquidsHELVETICA CHIMICA ACTA, Issue 11 2009Sifu Tang Abstract Two new Eu-based ionic liquid systems, [C4mim][DTSA],:,[Eu(DTSA)3] and 2[C4mim] [DTSA],:,[Eu(DTSA)3] were synthesized at 120° under inert conditions from 1-butyl-1-methylimidazolium ditoluenesulfonylamide ([C4mim][DTSA]). The identity and purity of the synthesized compounds were confirmed by elemental analysis, IR, Raman, and 1H-NMR spectroscopy. As they solidify below 100° as glasses they qualify as ionic liquids. Fluorescence measurements show that the materials exhibit a strong red luminescence of high color purity. Therefore, they have the potential to be used for optical applications such as in emission displays. [source] Microwave-assisted synthesis and anti-HIV activity of new benzenesulfonamides bearing 2,5-disubstituted-1,3,4-oxadiazole moietyHETEROATOM CHEMISTRY, Issue 4 2007Muhammad Zareef New benzenesulfonamides, most of which are chiral, incorporating 1,3,4-oxadiazole, and selected amino acid entities have been synthesized, using the microwave irradiation method. Most of the synthesized compounds were tested against HIV activity. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:425,431, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20316 [source] Synthesis and anti-HIV activity of new chiral 1,2,4-triazoles and 1,3,4-thiadiazolesHETEROATOM CHEMISTRY, Issue 3 2007Tashfeen Akhtar 5-substituted 4-(4-chlorophenyl)-4H-1,2,4-triazol-3-thiones 3 and 2-substituted 5-(4-chlorophenylamino)-1,3,4-thiadiazoles 4 were prepared from the intermediate thiosemicarbazides 2 under basic and acidic conditions, respectively. The thiosemicarbazides, in turn, were prepared by the reaction of hydrazides 1 with 4-chlorophenylisothiocyanate in MeOH. Some of the new synthesized compounds were assayed against HIV-1 and HIV-2 in MT-4 cells. All the compounds were inactive except 3f, which showed an EC50 value of 23.9 ,g/mL and 9.9 ,g/mL against HIV-1 and HIV-2 with a therapeutic index of 3 and 7, respectively. It means that compound 3f was cytotoxic to MT-4 cells at CC50 of 72.7 ,g/mL in both strains. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:316,322, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20282 [source] Synthesis of some novel imidazolidine derivatives and their metal complexes with biological and antitumor activityHETEROATOM CHEMISTRY, Issue 7 2006Shaya Y. Al-Raqa Halogenated imidazo(pyrazine,[1,4]diazocine and quinoxaline), 9,10-anthraquinone- [6,7-e], phenanthroline[5,6-e] {imidazo[4,5-b]pyrazine}, and naphtho[1,8-ef]imidazo[4,5-b][1,4] diazipen were obtained through interaction of imidazolidineiminothiones with the corresponding diamino compounds. Imidazo[4,5-e] triazine and pyrrolo[2,3-d]imidazole were prepared when the iminothiones were reacted with thiocarbohydrazide and with ethylphenyl acetate, separately. Some of the synthesized compounds exhibited better biological and antitumor activities. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:634,647, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20244 [source] Synthesis, spectral, and antimicrobial studies of 1-butyl-3-substituted-4-(2-aryl-1H -indol-3-yl)-2-azetidinonesHETEROATOM CHEMISTRY, Issue 7 2004Vijai N. Pathak Ketene generated from acetyl chloride or chloroacetyl chloride adds on indolyl Schiff's base double bond to afford 1-butyl-3-substituted-4-(2-aryl-1H -indol-3-yl)-2-azetidinones in THF. The reaction proceeds stereospecifically via concerted trans [2+2] cycloaddition. The synthesized compounds have been characterized by elemental analyses and spectral data (IR, PMR, and mass). All synthesized compounds have been evaluated for antibacterial and antifungal activities, and 4g to 4l have shown promising results. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:494,501, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20052 [source] Heterocyclic synthesis containing bridgehead nitrogen atom: Synthesis of 3-[(2H)-2-oxobenzo[b]pyran-3-yl]- s -triazolo[3,4- b]-1,3,4-thiadiazine and thiazole derivativesHETEROATOM CHEMISTRY, Issue 2 2003M. A. Raslan The reaction of 2H-2-oxobenzo[b]pyran-3-hydrazide (2) with carbon disulfide in basic DMF afforded potassium thiocarbamate 3, which readily underwent heterocyclization upon its reaction with hydrazine and/or phenacyl bromide to yield 1,2,4-tiazole (4) and thiazole 7 derivatives, respectively. Condensation of 4 with substituted phenacyl bromide and/or chloranil gave 1,2,4-triazole[3,4-b]thiadiazine (5a,b) and 3,10-bis-[2H-2-oxobenzo[b]pyran-3-yl]-6,13-dichloro-bis-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazino[5,,6,-b:5,,6,-e]cyclohexa-1,4-diene (6), respectively. Cyclization of thiosemicarbazide 10 by refluxing it in sodium hydroxide and/or phosphoryl chloride afforded triazole 13 and thiadiazole 15 derivatives, respectively. Also, 10 reacted with phenacyl bromide in the presence of anhydrous sodium acetate to give the oxothiazolidine derivative 17. The structure of the synthesized compounds were confirmed by elemental analyses, IR, 1H NMR, and mass spectra. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:114,120, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10109 [source] Reactivity of cyanothioformamides and 3-(4-bromophenyl)-5-imino-4-oxazolidinethione toward ortho-substituted nucleophilesHETEROATOM CHEMISTRY, Issue 7 2002Mohamed S. A. El-Gaby The substituted benzoazoles 4 and 5a,b were obtained by the reaction of cyanothioformamides 1d and 1b or 1c with o-substituted aromatic amines 2b and 2c, respectively. Fused pyrimidinones 10, 12, and 14 were synthesized by the reaction of oxazolidinethione (9) with 2-amino aromatic and heteroaromatic carboxylic acids. The structures of the synthesized compounds were established based on elemental analysis and spectral data studies. © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:611,616, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10042 [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 and antifungal activity of spiro[cyclopropane-1,4,-pyrazol-3-one] derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2008Hiroshi Maruoka A series of new spiro[cyclopropane-1,4,-pyrazol-3-one] derivatives 3a-h were synthesized by the reaction of 4-arylidene-3H -pyrazol-3-one 1 with secondary and tertiary carbanions derived from a methylene and methine group bearing both a leaving group and electron-withdrawing group, e.g. methyl chloroacetate, ethyl chloroacetate, isopropyl chloroacetate, tert -butyl chloroacetate, chloroacetonitrile, 2-chloro- N,N -diethylacetamide, methyl 2-chloropropionate and 2-chloropropionitrile, in the presence of sodium hydride. All the synthesized compounds 3a-h were active against Candida albicans with MIC , 25 ,g/mL in vitro. [source] Synthesis, structure and some reactions of 4a',5,,6,,7,,8,,8a'-hexahydro-4,H -spiro[cyclohexane-1,9,-[1,2,4]triazolo[5,1- b]-quinazolines]JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2008Victor M. Chernyshev 2,-Substituted 5,,6,,7,,8,-tetrahydro-4,H -spiro[cyclohexane-1,9,-[1,2,4]triazolo[5,1- b]quinazolines] 3a-d were synthesized by condensation of 3-substituted 5-amino-1,2,4-triazoles 1a-d with 2-cyclohexylidene cyclohexanone 2 in DMF. The compounds 3 were hydrogenated with sodium borohydride in ethanol to give 2,-substituted cis -4a',5,,6,,7,,8,,8a'-hexahydro-4,H -spiro[cyclohexane-1,9,-[1,2,4]triazolo[5,1- b]quinazolines] 4a-d in high yields. The reactions of alkylation, acylation and sulfonylation of the compounds 4 were studied. The structure of the synthesized compounds was determined on the basis of NMR measurements including HSQC, HMBC, NOESY techniques and confirmed by the X-ray analysis of 6 and 11b. The described synthetic protocols provide rapid access to novel and diversely substituted hydrogenated [1,2,4]triazolo[5,1- b]quinazolines. [source] Synthesis and characterization of some important indazolyl derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2007S. B. Kale A series of some important indazolyl derivatives of pyrazoles, diazepines, thiopyrimidines, thiazines and chromones were synthesized and characterized with the help of spectral data. Some of the synthesized compounds are tested for antimicrobial and antioxidant activities. [source] Synthesis of some thiazolyl and thiadiazolyl derivatives of substituted furan and pyrroleJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 1 2007Seham Y. Hassan Four series of substituted furan and pyrrole have been synthesized. The first series was prepared by cyclization of the key intermediates ethyl 5-[(4-substituted thiosemicarbazido)methyl]-2-methylfuran-3-carboxylates 2a-2d and 1-[(4-acetyl-5-methyl-1H -pyrrol-2-yl)methylene]-4-substituted thiosemicarbazides 8a-8d with chloroacetic acid or (ethyl bromoacetate) to afford the corresponding 4-oxo-3-substituted thiazolidin-2-ylidene 3a-3d or 3-substituted thiazolidin-4-one 9a-9d. On the other hand, heating of the intermediates 2a-2d or 8a-8d with acetic anhydride afforded the corresponding (N -substituted acetylamino)-2,3-dihydro-[1,3,4]thiadiazol-2-yl derivatives 4a-4d and [1,3,4]thiadiazol-2-yl- N -substituted acetamide 10a-10d respectively, while cyclization with p -bromophenacyl bromide gave rise to the corresponding 3-substituted thiazol-2-yl-ylidene 5a-5d and 11a-11d respectively. Furthermore, 4-oxo-3-substituted thioureido-thiazolidin-2-yl 6a-6d or 4-oxo-thiazolidin-3-yl-3-substituted thiourea 12a-12d were obtained by reaction of the intermediates 2a-2d or 8a-8d with thioglycolic acid. Some of the synthesized compounds showed promising antimicrobial activities. [source] Design and synthesis of new trehalose-conjugated pentapeptides as inhibitors of A,(1,42) fibrillogenesis and toxicity,JOURNAL OF PEPTIDE SCIENCE, Issue 3 2009Paolo De Bona Abstract Aggregation of the amyloid A, peptide and its accumulation into insoluble deposits (plaques) are believed to be the main cause of neuronal dysfunction associated with Alzheimer's disease (AD); small molecules that can interfere with the A, amyloid fibril formation are therefore of interest for a potential therapeutic strategy. Three new trehalose-conjugated peptides of the well known ,-sheet breaker peptide iA,5p, were synthesized. The disaccharide was covalently attached to different sites of the LPFFD peptide chain, i.e. at the N-terminus, C-terminus or at the Asp side chain. CD spectroscopy in different solvents was used to assess changes in the peptide conformation of these compounds. The effects of these glycopeptides on the self-assembly and morphology of A, aggregates were investigated by ThT fluorescence assay and dynamic Scanning Force Microscopy, respectively. All the synthesized compounds were tested as inhibitors of A, toxicity toward pure cultures of rat cortical neurons. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. [source] Photochromism of dihydroindolizines part VII: multiaddressable photophysical properties of new photochromic dihydroindolizines bearing substituted benzo[i]phenanthridine as a fluorescing moiety,JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 8 2007Saleh Abdel-Mgeed Ahmed Abstract Sixteen benzo[i]phenanthridine derivatives 8a-p were prepared via photocyclization of cis-trans substituted 4-styrylquinolines in low-to-moderate yields. The chemical structure of the photocyclized benzo[i]phenanthridine derivatives was unambiguously elucidated by means of both spectral and analytical tools. The photochromic (PC) dihydroindolizines (DHIs) 8a-p based on benzo[i]phenanthridines were prepared in 19,57% yields via nucleophilic addition of benzo[i]phenanthridines 4a-p to spirocyclopropenes 5. The 1D, 2D, NOESY NMR spectra, mass spectrometry, and elemental analysis were used for characterization of the chemical structures of the newly synthesized DHIs 8a-p. Developing and tuning of the photophysical properties of the synthesized compounds by substituents in the base part have been achieved. The absorption maxima (,max) and the half-lives (t1/2) of the colored zwitterionic forms 7a-p were detected in all cases by flash-photolysis measurements due to the fast 1,5-electrocyclization back to the DHI system. Irradiation of DHI 8a-p in'CH2Cl2 solution with polychromatic light leads to the formation of green to green,blue colored betaines 7a-p after cooling with liquid nitrogen. The kinetics of the fast bleaching process of betaines 7a-p to DHIs 8a-p, studied by flash photolysis as well as low temperature FT-UV/VIS, were found to take place in the millisecond range (432,2675,ms) in dichloromethane solution and fitted well a first-order thermal back reaction. The fluorescence spectra as well as the fluorescence quantum yield were studied. Noticeable bathochromic and hypsochromic shifts in the emission spectra by changing the substituents in the base part were monitored. Interestingly, the photo-fatigue resistance of some studied betaines 7a-p showed a higher t30 -value than the standard one (dicyanopyridazine DHI). Large solvatochromic effects on the absorption maxima (,max) as well as a substantial increase in the half-lives (t1/2) with solvent polarity of betaines 7a-p were also observed. The multiaddressable PC properties of DHIs 8a-p will help these compounds to find applications. Copyright © 2007 John Wiley & Sons, Ltd. [source] Synthesis of benzotriazole derivatives as antioxidants for industrial lubricating oilsLUBRICATION SCIENCE, Issue 2 2006El-S.H. El-Ashry Abstract Evaluation of a number of benzotriazole derivatives as antioxidants for turbine oils was carried out by formulating different blends of turbine oil with viscosity grade ISO 46 with different dosages of the synthesized compounds. Oxidation tests were carried out according to IP 229 on each blend and the optimum dosages of these compounds were determined. Copyright © 2006 John Wiley & Sons, Ltd. [source] Toward a Cohesive Theory of Polymerization Volume Change, 1MACROMOLECULAR THEORY AND SIMULATIONS, Issue 2 2005Andrew J. Holder Abstract Summary: Rational design of polymer-based composites must include an understanding of how and why polymerization volume change occurs. Computational chemistry methods offer significant leverage in such processes. An obstacle to their use has been the meager amount of systematic volume change data collected under the same conditions and using the same methods. This work provides volume change data for eight oxiranes using the mercury dilatometry method. Densities of pure monomers are often unknown for newly synthesized compounds, but are required for the correction of the composite to monomer volume change. The densities have been estimated here by the application of a newly-developed quantum mechanically-based quantitative structure property relationship (QMQSPR). This computational chemistry model can be used to estimate densities of a large array of organic compounds with sufficient accuracy for most routine purposes. These results are presented herein. Correspondence between experimental and QMQSPR calculated results for densities. [source] 1H and 13C NMR spectral assignments of some novel 2,4,6,8-tetraaryl-3,7-diazabicyclo[3.3.1]nonan-9-one derivativesMAGNETIC RESONANCE IN CHEMISTRY, Issue 8 2008Paramasivam Parthiban Abstract The 1H and 13C NMR spectra of 2,4,6,8-tetraaryl-3,7-diazabicyclo[3.3.1]nonan-9-ones (1,2), oximes (3,8) and O -benzyl oximes (9,12) were recorded. The chemical shifts were unambiguously assigned using 1D and 2D NMR spectral data. The results clearly indicate that the compounds exist in chair-boat conformation with equatorial and axial orientation of the aryl groups in the chair and boat forms, respectively. Since the molecules are flexible and dynamic in solution, the chair and boat forms are mutually interconvertible. In 3,12, because of the effect of oximation/oximination, all the protons in the heterobicyclic systems gave distinct signals except the benzylic protons of the boat form. In all synthesized compounds, the aryl group protons at C-6,8 are shielded by the aryl groups at C-2,4 and therefore appear in the lower frequency region than the aryl groups at C-2,4. Copyright © 2008 John Wiley & Sons, Ltd. [source] Chemical modification of chitosan: synthesis and biological activity of new heterocyclic chitosan derivativesPOLYMER INTERNATIONAL, Issue 2 2008Mohamed EI Badawy Abstract BACKGROUND: Numerous works have been published on the chemical modification of chitosan; this polymer is still being modified, leading to various derivatives with improved properties. In the present study, heterocyclic aldehydes including furan-2-carbaldehyde, 5-methylfuran-2-carbaldehyde, 3-pyridine carboxyaldehyde, benzo[d][1,3]dioxole-5-carbaldehyde and 4-oxo-4H -chromene-3-carbaldehyde were reacted with chitosan by a reductive alkylation reaction to produce for the first time five new N -heterocyclic chitosan derivatives to improve the biological activity of chitosan against the most important economic plant pests including fungi and insects, in particular the cotton leafworm Spodoptera littoralis. RESULTS: The chemical structures of the synthesized compounds were confirmed by 1H NMR spectroscopy and the degree of substitution ranged from 0.30 to 0.43. The fungicidal assessment was investigated in vitro using a mycelia radial growth inhibition technique against soil-borne pathogenic fungi Fusarium oxysporum and Pythium debaryanum and the rice leaf blast Pyricularia grisea. The results showed that N -[(5-methylfuran-2-yl)methyl] chitosan was the most active against P. grisea with an EC50 value of 0.919 mg mL,1 while N -(benzo[d][1,3]dioxol-5-ylmethyl) chitosan and N -(methyl-4H -chromen-4-one) chitosan exhibited the most potent fungicidal activity against P. debaryanum and F. oxysporum. An insecticidal bioassay against the larvae of S. littoralis showed that N -(methyl-4H -chromen-4-one) chitosan exhibited a significant growth inhibition and antifeedant activity among the synthesized compounds. CONCLUSION: The chemical modification of chitosan molecule with a heterocyclic moiety led to an enhancement in the biological activity against the plant pathogenic fungi F. oxysporum, P. debaryanum and P. grisea and the cotton leafworm insect S. littoralis. Copyright © 2007 Society of Chemical Industry [source] Synthesis, characterization and biological properties of sulfonamide-derived compounds and their transition metal complexesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 8 2009Zahid H. Chohan Abstract Sulfonamide-derived compounds and their first row d-transition metal chelates [cobalt(II), copper(II), nickel(II) and zinc(II)] have been synthesized and characterized. The nature of bonding and structure of all the synthesized compounds have been proposed from magnetic susceptibility and conductivity measurements, IR, 1H and 13C NMR, electron spectra, mass spectrometry and CHN analysis data. The structure of ligand, 4-{[(E)-(5-chloro-2-hydroxyphenyl) methylidene] amino}- N -(4,6-dimethyl pyrimidin-2-yl) benzene sulfonamide has also been determined by X-ray diffraction method. An octahedral geometry has been suggested for all the complexes. The ligands and metal complexes have been screened for their in vitro antibacterial, antifungal and cytotoxic activity. The results of these studies revealed that all compounds showed moderate to significant antibacterial activity against one or more bacterial strains and good antifungal activity against various fungal strains. Copyright © 2009 John Wiley & Sons, Ltd. [source] Hydroxylated Analogs of Mexiletine as Tools for Structural-Requirements Investigation of the Sodium Channel Blocking ActivityARCHIV DER PHARMAZIE, Issue 6 2010Alessia Catalano Abstract [2-(2-Aminopropoxy)-1,3-phenylene]dimethanol 1 and 4-(2-aminopropoxy)-3-(hydroxymethyl)-5-methylphenol 2, two dihydroxylated analogs of mexiletine , a well known class IB anti-arrhythmic drug , were synthesized and used as pharmacological tools to investigate the blocking-activity requirements of human skeletal muscle, voltage-gated sodium channel. The very low blocking activity shown by newly synthesized compounds corroborates the hypothesis that the presence of a phenolic group in the para-position to the aromatic moiety and/or benzylic hydroxyl groups on the aromatic moiety of local anesthetic-like drugs impairs either the transport to or the interaction with the binding site in the pore of Na+ channels. [source] Synthesis and Antibacterial Activity of a Novel Series of 2,3-Diaryl-substituted-imidazo(2,1- b)-benzothiazole DerivativesARCHIV DER PHARMAZIE, Issue 6 2010Mahesh Palkar Abstract Benzothiazole and imidazole compounds are extensively studied heterocyclics due to their wide spectrum of bioactivities. Among them, the imidazo(2,1- b)-benzothiazole derivatives are pharmacologically important because of their immunostimulant, anti-inflammatory, antifungal, antimicrobial, antitumor, and other activities. In the present research work, a novel series of 2,3-diaryl-substituted imidazo(2,1- b)-benzothiazoles 13a,o have been synthesized by reaction of substituted 2-aminobenzothiazoles 1,8 and an appropriately substituted ,-bromo-1-(4,,-substituted)-phenyl-2-(4,-substituted)-phenyl-1-ethanones 9,12 in the presence of anhydrous acetonitrile. They were characterized by physicochemical, elemental, and spectral (IR, 1H-NMR, and Mass) data. All the synthesized compounds were screened for their in-vitro antibacterial activity against Gram-positive, Gram-negative bacteria. The investigation of antibacterial screening data revealed that most of the compounds tested have demonstrated congruent activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa as compared with the standard ampicillin. Among the series, compounds 13d, 13h, and 13m exhibited excellent an antibacterial activity profile as compared with the standard. In summary, preliminary results indicate that some of the newly synthesized title compounds exhibited promising antibacterial activities and they warrant more consideration as prospective antimicrobials. [source] Synthesis and Antimycobacterial Activity of Azetidine-, Quinazoline-, and Triazolo-thiadiazole-containing PyrazinesARCHIV DER PHARMAZIE, Issue 4 2010Chandrakant G. Bonde Abstract The re-emergence of tuberculosis (TB) as a global health problem over the past few decades, accompanied by the rise of drug-resistant strains of Mycobacterium tuberculosis, emphasizes the need for the discovery of new therapeutic drugs against this disease. The emerging serious problem both in terms of TB control and clinical management prompted us to synthesize a novel series of N -[2-(substituted aryl)-3-chloro-4-oxoazetidin-1-yl]-2-(pyrazin-2-yloxy)acetamide, 6-(substituted aryl)-3-[(pyrazin-2-yloxy)methyl][1,2,4]triazolo[3,4- b][1,3,4]thiadiazole, and N -[6-({2-[(pyrazin-2-yloxy)acetyl] hydrazino}sulfonyl)-2-methyl-4-oxo-1,4-dihydroquinazolin-3(2H)yl]-substituted aryl sulfonamides. The compounds were synthesized using the appropriate synthetic route. All synthesized compounds were assayed in vitro for antimycobacterial activity against the H37 Rv strain of Mycobacterium tuberculosis. The minimum inhibitory concentration (MIC) was determined for the test compounds as well as for the reference standards. The compound which exhibited good antimycobacterial activity contains the substituents fluorine and methoxy. These electron-withdrawing or -donating substituents amend the lipophilicity of the test compounds which, in turn, alter the permeability across the bacterial cell membrane. Compounds 28, 37, and 43 showed good antimycobacterial activity while compound 51 showed a promising antimycobacterial activity. [source] Inhibitors of Human Histone Deacetylase: Synthesis and Enzyme Assay of Hydroxamates with Piperazine LinkerARCHIV DER PHARMAZIE, Issue 3 2010Shubhashis Chakrabarty Abstract The histone deacetylase (HDAC) enzyme plays an important role in gene transcription. Inhibitors of histone deacetylases induce cell differentiation and suppress cell proliferation in tumor cells. Hydroxamates with rigid linker have displayed better inhibition profiles than those with linear and flexible aliphatic linkers. We have designed and synthesized several potential histone deacetylase inhibitors with a piperazine moiety in the linker region to test the effect of reduced linker flexibility. Inhibitors were evaluated for their inhibitory action on human HDAC3/NCoR2 and HDAC8. N -Hydroxycarboxamide derivatives (compounds 4a,d) were found to be better than N -hydroxyacetamide derivatives (compounds 6a,d) against HDAC8. Amongst the synthesized compounds, 4a (HDAC8, IC50: 3.15 ,M) with no substitution in the aryl cap was the most active and promising lead for further investigations. [source] Anticonvulsant and Neurotoxicity Evaluation of Some Novel Kojic Acids and Allomaltol DerivativesARCHIV DER PHARMAZIE, Issue 3 2010Mutlu Dilsiz Aytemir Abstract A series of new 3-hydroxy-6-hydroxymethyl/methyl-2-substituted 4H -pyran-4-ones were synthesized and prepared by the reaction of kojic acid or allomaltol with piperidine derivatives and formaline as potential anticonvulsant compounds. The structure of the synthesized compounds was confirmed using the elemental analysis results and the spectroscopic techniques such as IR, 1H-NMR, and ESI-MS. Anticonvulsant activities were examined by maximal electroshock (MES) and subcutaneous Metrazol (scMet)-induced seizure tests. Neurotoxicity was determined by the rotorod toxicity test. All these tests were performed in accordance with the procedures of the Antiepileptic Drug Development (ADD) program. According to the activity studies and at all doses, 3-hydroxy-2-[(4-hydroxy-4-phenylpiperidin-1-yl)methyl]-6-methyl-4H -pyran-4-one (compound 1), 2-{[4-(4-chlorophenyl)-3,6-dihydropyridin-1(2H)-yl]methyl}-3-hydroxy-6-methyl-4H -pyran-4-one (compound 6), 2-[(4-acetyl-4-phenylpiperidin-1-yl)methyl]-3-hydroxy-6-(hydroxymethyl)-4H -pyran-4-one (compound 11), and 2-{[4-(4-chlorophenyl)-3,6-dihydropyridin-1(2H)-yl] methyl}-3-hydroxy-6-hydroxymethyl-4H -pyran-4-one (compound 12) were found to have anticonvulsant activity against MES-induced seizures at 4 h. Also, 2-{[4-(4-bromophenyl)-4-hydroxypiperidin-1-yl]methyl}-3-hydroxy-6-(hydroxymethyl)-4H -pyran-4-one (compound 8) was determined to be the most active compound against scMet-induced seizures at all doses at 0.5 and 4 h. In the rotorod neurotoxicity screening, all compounds showed no toxicity at all doses. [source] Synthesis and Evaluation of Novel Indolylthiadiazinoazetidinones and Indolylthiadiazinothiazolidinones as Antimicrobial AgentsARCHIV DER PHARMAZIE, Issue 2 2010Vikas Kumar Abstract Some new 5-methoxy/ethoxy-2,3-[2,-(3,,-chloro-2,,-oxo-4,,-substituted-aryl-1,,-azetidinyl)-1,,3,,4,-thiadiazino]indoles 13,20 and 5-methoxy/ethoxy-2,3-[2,-(2,,-substituted-aryl-4,,-oxo-1,,,3,,-thiazolidin-3,,-yl)-1,,3,,4,-thiadiazino]indoles 21,28 have been synthesized from 5-methoxy/ethoxy-2,3-[2,-(substituted-benzylidinylimino)-1,,3,,4,-thiadiazino]indoles 5,12. These newly synthesized compounds were characterized by elemental and spectral analysis. Further, compounds 5,28 of the present series have been screened for their antibacterial and antifungal activities. Both minimal inhibitory concentration (MIC) and inhibition zones were determined in order to monitor the efficacy of the synthesized compounds. Compounds 14 and 16 were found to be the most potent members of the present series, they showed maximal antibacterial and antifungal properties much better than the standard drugs. [source] | |||||||||||||||||||||||||||||||||||||