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Hydrazide
Kinds of Hydrazide Selected AbstractsZinc Hydrazide and Zinc Alkoxide Hydrazide Cages with Zn4N8 and Zn4N6O Cores , Cluster Isomerism as a Result of Subtle Changes in Ligand SizeEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2006Surajit Jana Abstract The hydrazide cluster [(iPrZn)4(NHNMe2)4] (1) was synthesised by the reaction of diisopropylzinc with N,N -dimethylhydrazine and was characterised by 1H- and 13C NMR and IR spectroscopy, mass spectrometry, elemental analysis and X-ray crystallography. This compound forms asymmetric aggregates containing Zn4N8 cores. The Zn atoms in these aggregates are arranged in topological tetrahedra in which the triangular faces are bridged by NHNMe2 substituents. Each NH group is connected to two Zn atoms and each NMe2 group to one Zn atom. Alkoxide clusters were prepared in one-pot syntheses by treating diisopropylzinc solutions with mixtures of N,N -dimethylhydrazine and ROH (R = Et, iPr). The resulting compounds have the formula [(iPrZn)4(NHNMe2)3(OR)] [R = Et (3), iPr(4)] and contain Zn4N6O cages, such that one NHNMe2 in 1 is replaced by one alkoxide group. Two different aggregation modes were found for these Zn4N6O cages. In compound 3, one Zn atom is bound to two NMe2 groups and one NH group. The other three Zn atoms each have three bonds to NH groups and one dative bond to an NMe2 group. The cage consists of one four-membered and one six-membered ring as well as four five-membered rings. In compound 4, the fourth zinc atom is exclusively bonded to three anionic NH functions in such a way that the rings in the cage are all five-membered. Compounds 3 and 4 were characterised by NMR spectroscopy and single-crystal X-ray diffraction. Hydrazide hydroxide clusters were also obtained through the reaction of a diisopropylzinc solution with N,N -dimethylhydrazine and a small amount of water. The structure of the resulting cocrystalline material, [(iPrZn)4(NHNMe2)4]·[(iPrZn)4(NHNMe2)3(OH)] (2), was also confirmed by X-ray diffraction. The hydroxide cluster in 2 contains a Zn4N6O cage, with a similar aggregation mode to that of 4. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Synthesis of Components for the Generation of Constitutional Dynamic Analogues of Nucleic AcidsHELVETICA CHIMICA ACTA, Issue 1 2008David Abstract The introduction of dynamic covalent polymers, in which the monomer units are linked by reversible covalent bonds and can undergo component exchange, opens up new possibilities for the generation of functional materials. Extending this approach to the generation of dynamic biopolymers in aqueous media, which are able to adapt constitution (sequence, length) to external factors (e.g., environment, medium, template), would provide an alternative approach to the de novo design of functional dynamic bio-macromolecules. As a first step towards this goal, various mono- and bifunctionalised (hetero- and homotopic) nucleic acid-derived building blocks of type I,X have been synthesised for the generation of dynamic main-chain and side-chain reversible nucleic acid analogues. Hydrazide- and/or acetal (protected carbonyl)-functionalised components were selected, which differ in terms of flexibility, length, net formal charge, and hydrazide/acetal substituents, in order to explore how such factors may affect the properties (structure, solubility, molecular recognition features) of the polymer products that may be generated by polycondensation. [source] ChemInform Abstract: Reaction of Hydrazide of (Tetrazol-5-yl)acetic Acid with Isothiocyanates and Antimicrobial Investigations of Newly-Obtained Compounds.CHEMINFORM, Issue 13 2008Monika Wujec 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] trans-4-Hydroxy-L-proline Hydrazide,Trifluoroacetic Acid as Highly Stereoselective Organocatalyst for the Asymmetric Direct Aldol Reaction of Cyclohexanone.CHEMINFORM, Issue 4 2007Chuanling Cheng 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, please click on HTML or PDF. [source] Synthesis, Stereochemistry and Biological Activity of Some Novel Long Alkyl Chain Substituted Thiazolidin-4-ones and Thiazan-4-one from 10-Undecenoic Acid Hydrazide.CHEMINFORM, Issue 26 2005V. P. Mujeebur Rahman Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis and Antimicrobial Activity of Some New Hydrazones of 4-Fluorobenzoic Acid Hydrazide and 3-Acetyl-2,5-disubstituted-1,3,4-oxadiazolines.CHEMINFORM, Issue 50 2002Sevim Rollas Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: Synthesis of Hydrazide of Benzothiazolyl-2-thioacetic Acid.CHEMINFORM, Issue 49 2002M. A. Silin Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 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] Quantification of carbonylated proteins in rat skeletal muscle mitochondria using capillary sieving electrophoresis with laser-induced fluorescence detectionELECTROPHORESIS, Issue 2 2008Juan Feng Abstract Carbonyl-modified proteins are markers of oxidative damage. Here, we report a new method for detecting and quantifying carbonylated proteins by capillary sieving electrophoresis (CSE) with LIF detection (CSE-LIF). Alexa 488 hydrazide is used for the specific labeling of carbonyls while 3-(2-furoyl) quinoline-2-carboxaldehyde (FQ) is used for protein labeling. BSA subjected to metal-catalyzed oxidation is used to optimize the labeling reactions, confirm the separation power of CSE, and characterize the response of the LIF detector. The method is capable of detecting femtomole (fmol) amounts of carbonyls in proteins with molecular masses ranging from 26 to 30,kDa. Using this method, we determined that mitochondrial proteins isolated from skeletal muscle contains 2.1,±,0.1 (average,±,SD; n,=,3) nmol carbonyl/mg protein. The methodology described here should be compatible with the analysis of single cells and needle biopsies taken from oxidative stress animal models. [source] Anticlastogenic, antitoxic and sorption effects of humic substances on the mutagen maleic hydrazide tested in leguminous plantsEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 3 2004G. Ferrara Summary The potential anticlastogenic and antitoxic effects of a soil humic acid (HA), a peat HA and a peat fulvic acid (FA) on the mutagen maleic hydrazide (MH) have been investigated in two legume species, Vicia faba and Pisum sativum. Both HAs and FA were tested at two different concentrations, 20 and 200 mg l,1, either alone or after 24-hour interaction with 10 mg l,1 of MH before addition to the legume seeds. Anticlastogenicity, i.e. an antimutagenic action defined as the capacity for minimizing chromosome breakages, was evaluated by counting both micronuclei (MN) and aberrant anatelophases (AAT) in root-tip cells. Length and dry weight of the seedling primary root were measured to test the antitoxic activity of HA and FA on MH. The possible occurrence and extent of adsorption or desorption of MH onto or from HA were also investigated. The two species responded differently to the anticlastogenic tests, with V. faba showing a greater number of MN and AAT anomalies than P. sativum. Peat HA and FA exhibited anticlastogenic and antitoxic activities of similar intensity and greater than those of soil HA. The adsorption capacity of both HAs for MH was small, thus suggesting that adsorption is not a major mechanism responsible for the reduction of clastogenicity and antitoxicity of MH by HA. [source] Synthesis, structure, and antibacterial evaluation of new N -substituted-3-amino- 5-oxo-4-phenyl-2,5-dihydro-1H -pyrazole-1-carbothioamidesHETEROATOM CHEMISTRY, Issue 4 2010Monika Pitucha Novel N -substituted-3-amino-5-oxo-4-phenyl-2,5-dihydro-1H -pyrazole-1-carbothioamide derivatives were synthesized by means of two methods. First is the cyclization reaction of 1-(cyanophenyl)acetyl-4-substituted thiosemicarbazide, and the second one is reaction of cyanophenyl acetic acid hydrazide with isothiocyanate. Structures of new compounds were confirmed by elemental analysis, 1H NMR, and X-ray diffraction analysis. Biological evaluation showed that some of them possess promising antibacterial activities. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:215,221, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20598 [source] Tuberculosis verrucosa cutis: antitubercular therapy, a well-conceived diagnostic criterionINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 3 2005Virendra N. Sehgal MD A 39-year-old housewife sustained inadvertent trauma to the right index finger about 6 years ago, whilst stitching clothes. A couple of weeks later, the site of trauma became hard and gritty. Ever since, it has progressed slowly, without any appreciable outward sign. It was not associated with any discomfort/pain. Consequent on an opinion from a surgeon, it was decided to operate on the right index finger. During the operation, under local anesthesia, a hard and gritty material was removed. The material was subjected to histopathologic study. Several stitches were applied to the wound. It failed to respond to antimicrobial therapy over a 4-week period, prompting the patient to seek another opinion. Examination of the skin surface revealed a plaque with an irregular configuration on and around the distal interphalangeal joint of the right index finger. It was erythematous and pigmented. The top of the plaque was irregular and had alternating elevations and depressions (Fig. 1). Diascopy was negative for apple jelly nodule. A bacillus Calmette,Guérin (BCG) vaccination scar was identified on the left deltoid. There was no regional lymphadenopathy or systemic abnormality. Mantoux test with intradermal injection of 0.1 mL SPAN's tuberculin (purified protein derivative/5 tuberculin units/0.1 mL) (Span Diagnostic Ltd., Murat, India) was negative after 72 h. Investigations, including total and differential leukocyte count, erythrocyte sedimentation rate, serum biochemistry, and renal and liver function tests, were within the normal range, as was a chest X-ray. Figure 1. Tuberculosis verrucosa cutis before (a) and after (b) antitubercular therapy (ATT) Hematoxylin and eosin-stained sections prepared from the biopsy taken from the lesion revealed noteworthy changes in the epidermis and the dermis. The former was marked by the presence of hyperkeratosis, acanthosis, and papillomatosis, whilst the latter contained tubercle granulomas. Each of the granulomas was well formed and consisted of large numbers of lymphocytes, histiocytes, and foreign body (Langerhans') giant cells (Fig. 2). Caseation necrosis and acid-fast bacilli could not be demonstrated. The preceding revelations were fairly conducive to the diagnosis. Accordingly, antitubercular therapy (ATT), comprising 450 mg of rifampicin, 300 mg of isonicotinic acid hydrazide, and 800 mg of ethambutol, was recommended for oral administration each day for 60 days. The outcome of the treatment was satisfactory, resulting in perceptible regression of the skin lesion (Fig. 1b). The patient was advised to continue the treatment for another 30 days, after which 450 mg of rifampicin and 300 mg of isonicotinic acid hydrazide were to be continued for another 6 months. Figure 2. Tuberculosis verrucosa cutis depicting well-formed tubercle(s) comprising lymphocytes, histiocytes, neutrophils, and a few giant cells (hematoxylin and eosin, × 100) [source] Electrophysiological characterization of electrolyte and nutrient transport across the small intestine in horsesJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 3 2009A. Cehak Summary The aim of this study was to characterize the transport mechanisms of electrolytes and nutrients across the jejunum of nine healthy horses electrophysiologically. The stripped mucosa was mounted in Ussing chambers and tissue conductances (Gt) and short circuit currents (Isc) were continuously monitored. After blocking the sodium and potassium channels with amiloride, tetraethylammonium chloride (TEA) and barium, chloride secretion was stimulated by carbachol and forskolin. Subsequently, chloride channels were inhibited by 4,4,-diisothiocyanato-stilbene-2,2,-disulfonic acid, 5-nitro-2-(3-phenylpropylamino)benzoic acid, CFTRinh -172, N -(2-naphtalenyl)-(3.5-dibromo-2.4-dihydroxyphenyl)methylene glycine hydrazide (GlyH-101) and glibenclamide and their dose,response effect was investigated. The response to glucose, l -alanine and glycyl- l -glutamine was determined at two different mucosal pH values (pH 7.4 and 5.4 respectively). Mean basal Isc was ,0.47 ± 0.31 ,Eq/cm2h and mean Gt was 22.17 ± 1.78 mS/cm2. Amiloride and TEA did not alter the baseline Isc. Barium, carbachol and forskolin significantly increased Isc. Irrespective of the dose, none of the chloride inhibitors changed Isc. All nutrients induced a significant increase in Isc with the increase being significantly higher at pH 7.4 than at pH 5.4. In conclusion, there is evidence that chloride secretion in horses may be different from respective transport mechanisms in other species. The glucose absorption is suggestive of a sodium-dependent glucose cotransporter 1. However, a decrease in luminal pH did not stimulate current response to peptides as shown for other mammals. [source] Utilization of 2-benzo[b]furan carboxylic acid hydrazide in the synthesis of 1,3,4-oxadiazole derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 4 2009Yu-Xia Da In this study, the synthesis of series of 2-benzo[b]furan-substituted 1,3,4-oxadiazole derivatives using readily available 2-benzo[b]furan carboxylic acid hydrazide as starting material has been investigated. J. Heterocyclic Chem., (2009). [source] Synthesis and biological activity of 3-[(6-chloropyridin-3-yl)methyl]-6-substituted-6,7-dihydro-3H -1,2,3-triazolo[4,5- d]-pyrimidin-7-iminesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2008Xiao-Bao Chen A series of 3-[(6-chloropyridin-3-yl)methyl]-6-substituted-6,7-dihydro-3H -1,2,3-triazolo[4,5- d]pyrimidin-7-imines were designed and synthesized via a multi-step sequence using 2-chloro-5-(chloromethyl)-pyridine as the starting material. Various primary aliphatic amines, hydrazine and hydrazide reacted with 3 to obtain the cyclization products 4. Their structures were confirmed by 1H NMR and elemental analyses, some of them were also confirmed by IR, 13C NMR, MS and single crystal X-ray diffraction. The preliminary bioassay indicated that some of the target compounds 4 displayed moderate to weak fungicidal activity and insecticidal activity. [source] The condensation of active methylene reagents with salicylaldehyde: Novel synthesis of chromene, azaanthracene, pyrano[3,4-c]chromene and chromeno[3,4- c]pyridine derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2004Tarek M. Abu Elmaati On heating of the cyanoacetic acid cyclopentylidene hydrazide 1 with salicylaldehyde in the presence of bases the azaanthracene derivative 6 was formed. Also, reaction of 3 with malononitrile and ketones 10a,b afforded the pyrano[3,4- c]chromene 9 and chromeno[3,4- c]pyridine 11 respectively. A mechanism for these reactions is proposed. [source] Hydrophobic ion pairing of isoniazid using a prodrug approachJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 6 2002Huiyu Zhou Abstract Inhalation therapy for infectious lung diseases, such as tuberculosis, is currently being explored, with microspheres being used to target alveolar macrophages. One method of drug encapsulation into polymeric microspheres to form hydrophobic ion-paired (HIP) complexes, and then coprecipitate the complex and polymer using supercritical fluid methodology. For the potent antituberculosis drug, isoniazid (isonicotinic acid hydrazide, INH), to be used in this fashion, it was modified into an ionizable form suitable for HIP. The charged prodrug, sodium isoniazid methanesulfonate (Na,INHMS), was then ion paired with hydrophobic cations, such as alkyltrimethylammonium or tetraalkylammonium. The logarithms of the apparent partition coefficients (log P,) of various HIP complexes of INHMS display a roughly linear relationship with the numbers of carbon atoms in the organic counterions. The water solubility of the tetraheptylammonium,INHMS complex is about 220-fold lower than that of Na,INHMS, while the solubility in dichloromethane exceeds 10 mg/mL, which is sufficient for microencapsulation of the drug into poly(lactide) microspheres. The actual logarithm of the dichloromethane/water partition coefficient (log P) for tetraheptylammonium,INHMS is 1.55, compared to a value of ,,1.8 for the sodium salt of INHMS. The dissolution kinetics of the tetraheptylammonium,INHMS complex in 0.9% aqueous solutions of NaCl was also investigated. Dissolution of tetraheptylammonium,INHMS exhibited a first-order time constant of about 0.28 min,1, followed by a slower reverse ion exchange process to form Na,INHMS. The half-life of this HIP complex is on the order of 30 min, making the enhanced transport of the drug across biological barriers possible. This work represents the first use of a prodrug approach to introduce functionality that would allow HIP complex formation for a neutral molecule. © 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91:1502,1511, 2002 [source] Novel thermally stable poly(amine hydrazide)s and poly(amine-1,3,4-oxadiazole)s for luminescent and electrochromic materialsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 15 2005Guey-Sheng Liou Abstract We describe the preparation, characterization, and luminescence of four novel electrochromic aromatic poly(amine hydrazide)s containing main-chain triphenylamine units with or without a para-substituted N,N -diphenylamino group on the pendent phenyl ring. These polymers were prepared from either 4,4,-dicarboxy-4,- N,N -diphenylaminotriphenylamine or 4,4,-dicarboxytriphenylamine and the respective aromatic dihydrazide monomers via a direct phosphorylation polycondensation reaction. All the poly(amine hydrazide)s were amorphous and readily soluble in many common organic solvents and could be solution-cast into transparent and flexible films with good mechanical properties. These poly(amine hydrazide)s exhibited strong ultraviolet,visible absorption bands at 346,348 nm in N -methyl-2-pyrrolidone (NMP) solutions. Their photoluminescence spectra in NMP solutions or as cast films showed maximum bands around 508,544 and 448,487 nm in the green and blue region for the two series of polymers. The hole-transporting and electrochromic properties were examined by electrochemical and spectroelectrochemical methods. All obtained poly(amine hydrazide)s and poly(amine-1,3,4-oxadiazole)s exhibited two reversible oxidation redox couples at 0.8 and 1.24 V vs. Ag/AgCl in acetonitrile solution and revealed excellent stability of electrochromic characteristics, changing color from original pale yellow to green and then to blue at electrode potentials of 0.87 and 1.24 V, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3245,3256, 2005 [source] The emitting species formed by the oxidation of hydrazides with hypohalites or N-halosuccinimidesLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 4 2004Paul S. Francis Abstract The chemiluminescence accompanying the oxidation of salicylic hydrazide (2-hydroxybenzoic acid hydrazide) with hypochlorite, hypobromite, N-chlorosuccinimide, N-bromosuccinimide or hydrogen peroxide with cobalt(II) matched the photoluminescence emission of salicylic acid. In a related reaction, the oxidation of a mixture of isoniazid and ammonia, a synergistic effect was observed. The chemiluminescence spectrum for this reaction matches that accompanying the oxidation of the hydrazide, rather than the oxidation of ammonia. These results were used to assess mechanisms proposed by previous authors. Copyright © 2004 John Wiley & Sons, Ltd. [source] Hydrogen-Bonded Shape-Persistent Aryl Hydrazide Polymers: Side-Chain-Tuned Formation of Vesicles and OrganogelsMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 19 2010Cen Zhou Abstract A new class of aromatic, hydrazide-based, zigzag polymer has been synthesized using the Yamazaki polymerization conditions. Hydrophobic, hydrophilic or amphiphilic side chains are introduced to the backbones to tune their solubility in organic solvents of different polarities. The side chains form successive, intramolecular, six-membered RO···HN hydrogen bonds, which increase the planarity of the backbones. The new shape-persistent polymers are revealed to self-assemble into vesicles or fibers to gelate organic solvents of different polarities. The polymeric backbones may be regarded as a conceptual extension of the emerging foldamers, which are usually constructed from oligomeric backbones. [source] Biodegradable Poly(ester hydrazide)s via Enzymatic PolymerizationMACROMOLECULAR RAPID COMMUNICATIONS, Issue 16 2005Guillaume Métral Abstract Summary: The reaction of hydrazine with ethyl glycolate results in 1,2-bisglycoylhydrazine, a monomer that was used for the lipase-catalyzed synthesis of biodegradable poly(ester hydrazide)s. The polymers derived from the hydrazide-containing monomer and vinyl-activated adipic, suberic, and sebacic acid, respectively, showed low melting temperatures of 136 to 141,°C and are thermally stable up to 300,°C. The aliphatic poly(ester hydrazide)s (PEHs) are highly crystalline, as proven by polarization microscopy and atomic force microscopy. Further, the PEHs represent the first described biodegradable poly(hydrazide)s. They degrade in the presence of lipase at 37,°C within a few weeks. Synthetic route to poly(ester hydrazide)s. [source] Synthesis and Antimycobacterial Activity of a Novel Series of Isonicotinylhydrazide DerivativesARCHIV DER PHARMAZIE, Issue 12 2009Sandip Jaju Abstract A novel series of 14 new isonicotinyl hydrazide derivatives 2a,g, 3a,g containing a 4-thiazolidinone / 2-azetidinone nucleus were synthesized by reacting N,-substituted arylidene / heteroarylidene isonicotinyl hydrazide 1a,g with thioglycollic acid in the presence of dry benzene and with chloroacetyl chloride in the presence of triethylamine, respectively. Structures of all newly synthesized compounds were characterized on the basis of elemental analyses and spectral data (IR and 1H-NMR). All the title compounds were tested for their in-vitro antimycobacterial activity against Mycobacterium tuberculosis H37Rv using Alamar-Blue susceptibility test, and the activity is expressed as the minimum inhibitory concentration (MIC) in ,g/mL. Among the series, compounds 2b, 2g, 3b, and 3g displayed an encouraging antimycobacterial activity profile as compared to that of the reference drugs isoniazid / rifampicin. [source] Synthesis and Antibacterial Activity of a New Series of 3-[3-(Substituted Phenyl)-1-Isonicotinoyl-1H -Pyrazol-5-yl]-2H -Chromen-2-one DerivativesARCHIV DER PHARMAZIE, Issue 6 2009Prashant Aragade Abstract A novel series of 3-[3-(substituted phenyl)-1-isonicotinoyl-1H -pyrazol-5-yl]-2H -chromen-2-one derivatives 4a,k have been synthesized by the reaction of 3-[2,3-dibromo-3-(substituted phenyl) propanoyl]-2H -chromen-2-one 3a,k and isonicotinic acid hydrazide in the presence of triethylamine in absolute ethanol, characterized by spectral data and screened for their in-vitro antibacterial activity against Gram-positive and Gram-negative bacteria. Among the series, compounds 4e, 4i, and 4k displayed an encouraging antibacterial activity profile as compared to the reference drug ampicillin against tested bacterial strains. [source] Immunomodulatory and Anticancer Activities of Some Novel 2-Substituted-6-bromo-3-methylthiazolo[3,2- a]benzimidazole DerivativesARCHIV DER PHARMAZIE, Issue 4 2009Hatem A. Abdel-Aziz Abstract Ethyl 6-bromo-3-methyl-1,3-thiazolo[3,2- a]benzimidazole-2-carboxylate 2 was prepared by the ambient temperature bromination of ethyl 3-methyl-1,3-thiazolo[3,2- a]benzimidazole-2-carboxylate 1. The acid hydrazide 4 was obtained by the reaction of ester 2 with hydrazine hydrate. Treatment of compound 4 with benzaldehyde or 2-thiophenaldehyde yielded the corresponding hydrazones 6a and 6b, respectively, while the reaction of acid hydrazide 4 with ethoxymethylene malononitrile (7a) or with ethyl ethoxymethylene cyanoacetate (7b) in refluxing ethanol afforded pyrazole derivatives 9a and 9b, respectively. Taken together, from the biological investigations compounds 9a and 9b were the most significant inhibitors of LPS-stimulated NO generation from Raw murine macrophage 264.7, and, as another result, compounds 2 and 4 had a weak radical scavenging activity against DPPH radicals. Moreover, 2, 4, and 9a had a concomitant strong cytotoxicity against both colon carcinoma cells (HCT-116) and hepatocellular carcinoma cells (Hep-G2) while 9b showed specific cytotoxicity only against colon carcinoma cells. [source] Liposomes as tools to study drug diffusion and toxin-induced leaksBIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION, Issue 2 2002Florence Levillain Multilayered vesicles made of egg-phosphatidylcholine and of phosphatidic acid were used to teach in a 4-h session of practical work with a low cost spectrophotometer how to determine osmolarity inside multilayered vesicles and to show, by using two anti-tuberculous drugs (isonicotinic acid hydrazide, p -aminosalicylate), that a small and non-ionized molecule diffused freely through phospholipid vesicles, whereas a charged one did not. In addition, the permeabilizing effect of melittin, a membrane-targeted bee-venom toxin, was tested. [source] Tricarbonyl Rhenium(I) and Technetium(I) Complexes with Hydrazones Derived from 4,5-Diazafluoren-9-one and 1,10-Phenanthroline-5,6-dioneEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 29 2010Paula Barbazán Abstract Tricarbonylrhenium(I) and -technetium(I) halide (halide = Cl and Br) complexes of ligands derived from 4,5-diazafluoren-9-one (df) and 1,10-phenanthroline-5,6-dione (phen) derivatives of benzoic and 2-hydroxybenzoic acid hydrazides have been prepared. The complexes have been characterized by elemental analysis, MS, IR, 1H NMR and absorption and emission UV/Vis spectroscopic methods. The metal centres (ReI and TcI) are coordinated through the nitrogen imine atoms and establish five-membered chelate rings, whereas the hydrazone groups stand uncoordinated. The 1H NMR spectra suggest the same behaviour in solution on the basis of only marginal variations in the chemical shifts of the hydrazine protons. [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] Silver Triflate-Catalyzed or Electrophile-Mediated Tandem Reaction of N, -(2-Alkynylbenzylidene)hydrazides with Dimethyl AcetylenedicarboxylateADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2009Zhiyuan Chen Abstract Different outcomes were generated under different conditions for the tandem reactions of N, -(2-alkynylbenzylidene)hydrazides with dimethyl acetylenedicarboxylate (DMAD) catalyzed by silver triflate or in the presence of electrophiles. The unexpected isoquinoline-based azomethine ylides were obtained when the reaction was catalyzed by silver triflate or in the presence of bromine, while the fused 1,2-dihydroisoquinolines were afforded when iodine was employed in the above tandem reactions. [source] Sulfamic acid catalyzed one-pot synthesis of 2,5-diaryl-1,3,4-oxadiazoles under microwave irradiation and conventional heatingJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2009J. Venu Madhav Sulfamic acid has been found to be an efficient catalyst for the one-pot synthesis of novel 2,5-diaryl-1,3,4-oxadiazoles by condensation of different coumarinoyl hydrazides with various coumarinoyl or quinolinoyl chlorides under microwave irradiation and conventional heating. Some of the advantages of this method are low reaction times, operational simplicity, and high yields. J. Heterocyclic Chem., (2009) [source] Synthesis of thiadiazoles, triazoles and oxadiazoles from sulfonyl acetic acids via a common routeJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 1 2005Venkatapuram Padmavathi A new class of five membered heterocycles, thiadiazoles, triazoles and oxadiazoles were prepared from sulfonyl acetic acids via acid hydrazides. [source] The emitting species formed by the oxidation of hydrazides with hypohalites or N-halosuccinimidesLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 4 2004Paul S. Francis Abstract The chemiluminescence accompanying the oxidation of salicylic hydrazide (2-hydroxybenzoic acid hydrazide) with hypochlorite, hypobromite, N-chlorosuccinimide, N-bromosuccinimide or hydrogen peroxide with cobalt(II) matched the photoluminescence emission of salicylic acid. In a related reaction, the oxidation of a mixture of isoniazid and ammonia, a synergistic effect was observed. The chemiluminescence spectrum for this reaction matches that accompanying the oxidation of the hydrazide, rather than the oxidation of ammonia. These results were used to assess mechanisms proposed by previous authors. Copyright © 2004 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||