Synthesis of 5‐(1H‐Tetrazolyl)‐1‐hydroxy‐tetrazole and Energetically Relevant Nitrogen‐Rich Ionic Derivatives

Sodium 5‐cyanotetrazolate sesquihydrate ( 1 ) was prepared from sodium azide and two equivalents of sodium cyanide under acidic conditions. Sodium 5‐cyanotetrazolate sesquihydrate ( 1 ) reacts with hydroxylammonium chloride to form 5‐aminohydroximoyl tetrazole ( 2 ). 5‐Aminohydroximoyl tetrazole ( 2 ) is treated with sodium nitrite and hydrochloric acid to form 5‐chlorohydroximoyl‐tetrazole ( 3 ). The chloride azide exchange yields 5‐azidohydroximoyl‐tetrazole monohydrate ( 4 ). When compound 4 is treated with hydrochloric acid, 5‐(1H‐tetrazolyl)‐1‐hydroxytetrazole ( 5 ) is obtained in good yield. Compound 5 can be deprotonated twice by various bases. Different ionic derivatives such as bis(hydroxylammonium) ( 6 ), bis(hydrazinium) ( 7 ), bis(guanidinium) ( 8 ), bis(aminoguanidinium) ( 9 ), bis(ammonium) ( 10 ), and diaminouronium ( 11 ) 5‐(1‐oxidotetrazolyl)‐tetrazolate were synthesized and characterized. With respect to energetic use salts 6 and 7 are most relevant. Compounds 3 – 9 and 11 were characterized using low temperature single‐crystal X‐ray diffraction. All compounds were investigated by NMR and vibrational (IR, Raman) spectroscopy, mass spectrometry and elemental analysis. The thermal properties were determined by differential scanning calorimetry (DSC). The sensitivities towards impact ( 4 : 4 J, 5 : 40 J, 6 : 12 J, 7 : 40 J), friction: ( 4 : 60 N, 5 : 240 N, 6 : 216 N, 7 : 240 N), and electrical discharge ( 5 : 0.40 J, 6 : 0.75 J, 7 : 0.75 J), were investigated using BAM standards and a small scale electrostatic discharge tester. The detonation parameters of 5 – 7 were calculated using the EXPLO5.06 code and calculated (CBS‐4 M) enthalpy of formation values.     

Synthesis of novel tri- and tetrasubstituted C<Subscript>18</Subscript> furan fatty esters

A methylene-interrupted C₁₈ keto-acetylenic fatty ester (methyl 12-oxo-9-octadecynoate) was obtained from methyl ricinoleate by bromination-dehydrobromination followed by oxidation. Reaction of methyl 12-oxo-9-octadecynoate with bis(benzonitrile) palladium(II) chloride, allyl bromide, or methyl-allyl bromide furnished methyl 8-[5-hexyl-3-allyl-furan-2-yl]-octanoate (1, 56%) or methyl 8-[5-hexyl-3-(2-methyl-allyl)-furan-2-yl]-octanoate (2, 55%). Reaction of methyl 12-oxo-11-chloro-or 11-fluoro-9-octadeyynoate (prepared from methyl santalbate-methyl 11-E-9-octadecynoate, found in sandalwood, Santalum album, seed oil) with bis(benzonitrile) palladium(II) chloride gave methyl 8-(4-fluoro-5-hexyl-furan-2-yl)-octanoate (3, 50%) or methyl 8-(4-fluoro-5-hexyl-furan-2-yl)-octanoate (4, 50%), respectively. And when methyl 12-oxo-11-chloro- or 11-fluoro-9-octadecynoate was treated with a mixture of bis(benzonitrile) palladium(II) chloride, allyl bromide, or methyl-allyl bromide, the reaction yielded tetrasubstituted C₁₈ furan derivatives, viz, methyl 8-(3-allyl-4-chloro-5-hexyl-furan-2-yl)-octanoate (5, 54%), methyl 8-[4-chloro-5-hexyl-3-(2-methyl-allyl)-furan-2-yl)-octanoate (6, 54%), methyl 8-(3-allyl-4-fluoro-5-hexyl-furan-2-yl]-octanoate (7, 10%), and methyl 8-[4-fluoro-5-hexyl-3-(2-methyl-allyl)-furan-2-yl]-octanoate (8, 10%). The presence of a fluorine atom in the furan derivatives 4, 7, and 8 was readily characterized by the appearance of doublets for carbon nuclei, which were coupled to the fluorine atom in the ¹³C NMR spectra. All furan fatty derivatives from this work were characterized by NMR spectroscopic and mass spectrometric analyses. The yields of compounds 7 and 8 were very low (10%) despite attempts to improve the procedure by increasing the amounts of the reactants and catalyst.     

Antiplatelet Effect and Selective Binding to Cyclooxygenase (COX) by Molecular Docking Analysis of Flavonoids and Lignans

The known flavonoids ginkgetin (1), taiwanhomoflavone A (2), taiwanhomoflavone B (3), and taiwanhomoflavone C (4) and eight known lignans: justicidin B (9), justicidin C (10), justicidin D (11), chinensinaphthol methyl ether (12), procumphthalide A (13), procumbenoside A (15), and ciliatosides A (16) and B (17) were isolated from Cephalotaxus wilsoniana and Justicia species, respectively. The antiplatelet effects of the above constituents on human platelet-rich plasma (PRP) were evaluated. Of the compounds tested on human PRP, compounds 1, 4, 9, and 11 showed inhibition of secondary aggregation induced by adrenaline. Compound 1 had an inhibitory effect on cyclooxygenase-1 (COX-1). Molecular docking studies revealed that 1 and the related compounds apigenin (5), cycloheterophyllin (6), broussoflavone F (7), and quercetin (8) were docked near the gate of active site of COX-1. It indicated that the antiplatelet effect of 1, 4, 9, and 11 is partially owed to suppression of COX-1 activity and reduced thromboxane formation. Flavonoids, 1, 5, 6, 7, and 8 may block the gate of the active site of COX-1 and interfere the conversion of arachidonic acid to prostaglandin (PG) H₂ in the COX-1 active site.     

Peptide Bioconjugates of Electron‐Poor Metallocenes: Synthesis,Characterization, and Anti‐Proliferative Activity

We report the synthesis of metallocene compounds Cp₂M with two different electron‐withdrawing substituents on both cyclopentadienyl rings (hexafluoroacetone (HFA) and chlorobenzoyl ( 1 – 5 ); HFA and COOH ( 6 and 7 ), M=Fe or Ru). The COOH‐containing derivatives were used to synthesize peptide bioconjugates with enkephalin ( 8 and 9 ) and neurotensin ( 10 and 11 ) as well as fluorescein‐labeled neurotensin ( 12 ). All the molecules were fully characterized, including X‐ray structures for 6 and 7 . The physicochemical properties (lipophilicity and electrochemistry) and cytotoxicity on MCF‐7, HT‐29, and PT‐45 cancer cells were evaluated for selected compounds. Electrochemical investigation by cyclic voltammetry revealed that all bis‐substituted metallocenes are up to 300 mV harder to oxidize compared to the monosubstituted 2‐ferrocenylhexafluoropropan‐2‐ol (FcHFA: Δ${E{{{\rm f}\hfill \atop 0\hfill}}}$ =214 mV; disubstituted derivatives: up to Δ${E{{{\rm f}\hfill \atop 0\hfill}}}$ =512 mV; both vs. FcH^0/+). For the bis‐substituted compounds, log P determinations by RP‐HPLC showed increased lipophilicity in comparison to the monosubstituted FcHFA and RcHFA. Cellular uptake was investigated by fluorescence microcopy, and this revealed endosomal entrapment for 12 .     

Spin design of iron complexes on Fe-ZSM-5 zeolites

The spin state of iron ions in Fe-ZSM-5 zeolites can be purposefully varied by adsorption of gaseous probe molecules. The resulting Fe complexes with half-integer spin (, and ) can be reliably identified by electron paramagnetic resonance (EPR). A good correlation has been found between the concentration of surface sites active in low-temperature nitrous oxide decomposition and the concentration of low-spin () nitrosyl complexes of Fe formed after adsorption of NO molecules. Based on the analysis of the formation of such complexes under varying conditions, we conclude that these active sites contain a binuclear iron complex with S = 0 and three adsorbed NO molecules. An approach to investigate various Fe-containing sites in oxidation catalysts is discussed.     

Barium Salts of Tetrazole Derivatives – Synthesis and Characterization

The compounds barium tetrazolate ( 6 ), barium 5‐aminotetrazolate tetrahydrate ( 7 ), barium 5‐nitriminotetrazolate dihydrate ( 8 ), barium bis(1H‐5‐nitriminotetrazolate) tetrahydrate ( 9 ), barium 1‐methyl‐5‐nitriminotetrazolate monohydrate ( 10 ), and barium 2‐methyl‐5‐nitriminotetrazolate dihydrate ( 11 ) were synthesized by the reactions of barium hydroxide octahydrate and 1H‐tetrazole ( 1 ), 5‐aminotetrazole ( 2 ), 1,4H‐5‐nitriminotetrazole ( 3 ), 1‐methyl‐5‐nitriminotetrazole ( 4 ), and 2‐methyl‐5‐nitraminotetrazole ( 5 ), respectively. The compounds were characterized using multi‐nuclear NMR spectroscopy, vibrational (IR and Raman) spectroscopy, elemental analysis, and differential scanning calorimetry. The solid‐state structures of 7 – 11 were determined using low temperature X‐ray diffraction and a comprehensive characterization is given. In addition, the sensitivities (impact, friction, electrical discharge) of 6 – 11 were investigated and bomb calorimetric measurements were carried out.     

The effects of pH on the molecular distribution of water soluble ruthenium(II) hydrides and its consequences on the selectivity of the catalytic hydrogenation of unsaturated aldehydes

The effect of pH on the formation and equilibrium distribution of the water soluble ruthenium hydrides [HRuCl(TPPMS)₂]₂, [HRuCl(TPPMS)₃] and [H₂Ru(TPPMS)₄] (TPPMS=(3-sulfonatophenyl)diphenylphosphine sodium salt) was studied in aqueous solution by pH-potentiometric and

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NMR methods. Depending on the pH, [RuCl₂(TPPMS)₂]₂ and its hydrido-derivatives hydrolyse extensively, giving rise to formation of hydroxo-ruthenium complexes. It was established that at pH≤3.3 the dominant ruthenium(II) species was [HRuCl(TPPMS)₃], while at pH≥7 it was [H₂Ru(TPPMS)₄]. While [HRuCl(TPPMS)₃] catalyzed the slow, selective hydrogenation of the C=C bond in trans-cinnamaldehyde, [H₂Ru(TPPMS)₄] was found an active and selective catalyst for C=O reduction. Consequently, the selectivity of the hydrogenation of trans-cinnamaldehyde could be completely inverted by minor changes in the solution pH, shifting the equilibrium between [HRuCl(TPPMS)₃] and [H₂Ru(TPPMS)₄].     

Identification of Bioactivity,Volatile and Fatty Acid Profile in Supercritical Fluid Extracts of Mexican arnica

Supercritical fluid extraction (SFE) is a sustainable technique used for the extraction of lipophilic metabolites such as pigments and fatty acids. Arnica plant is considered a potential candidate material with high antioxidant and antimicrobial activities. Therefore, in this study, a locally available Heterotheca inuloides, also known as Mexican arnica, was analyzed for the extraction of high-value compounds. Based on different pressure (P), temperature (T), and co-solvent (CoS), four treatments (T) were prepared. A maximum 7.13% yield was recovered from T2 (T = 60 °C, P = 10 MPa, CoS = 8 g/min), followed by 6.69% from T4 (T = 60 °C, P = 30 MPa, CoS = 4 g/min). Some bioactive sesquiterpenoids such as 7-hydroxycadalene, caryophyllene and δ-cadinene were identified in the extracts by GC/MS. The fatty acid profile revealed that the main components were palmitic acid (C16:0), followed by linoleic acid (C18:2ω6c), α-linolenic acid (C18:3ω3) and stearic acid (C18:0) differing in percent yield per treatment. Antibacterial activities were determined by the agar diffusion method, indicating that all the treatments exerted strong antibacterial activity against S. aureus, C. albicans, and E. coli strains. The antioxidant capacity of the extracts was also measured by three in vitro assays, DPPH, TEAC and FRAP, using Trolox as a standard. Results showed high antioxidant capacity enabling pharmaceutical applications of Mexican arnica.     

Synthesis, In vitro Antifungal and Antitumour Activity of Some Triorganotin(IV) N,C,N-Chelates

The in vitro antifungal activity of compounds 1-3 ({[(CH3)2NCH2]2C6H3}R2SnX; (where X=Cl, R=n-Bu for 1, X=Br, R=n-Bu for 2 and x=PF6, R=n=Bu for 3)) was estimated with the help of a modified microdilution format of the M27-A guidelines and was compared with in vitro activity of their diphenyltin(IV) analogues 4 and 5 (where X=Br, R=Ph for 4 and X=PF6, R=Ph for 5), and of drugs currently in clinical use (ketoconazole, fluconazole and amphotericin B). It was found that in coordinating solvents the more soluble derivative 2 is less active than the phenyl one (4), and compounds 1 and 3 are even inactive.In this paper, the in vitro antitumour activity of ionic diphenyltin(IV) complexes 4 and 5 against seven tumoural cell lines of human origin is also reported. The preparation and characterization (H1, C13 and Sn119 NMR spectroscopy and electrospray ionization mass spectrometry) of the novel compound 3 is mentioned too.     

Phenolic Compounds from Halimodendron halodendron (Pall.) Voss and Their Antimicrobial and Antioxidant Activities

Halimodendron halodendron has been used as forage in northwestern China for a long time. Its young leaves and flowers are edible and favored by indigenous people. In this study, eleven phenolic compounds were bioassay-guided and isolated from the aerial parts of H. halodendron for the first time. They were identified by means of physicochemical and spectrometric analysis as quercetin (1), 3,5,7,8,4′-pentahydroxy-3′-methoxy flavone (2), 3-O-methylquercetin (3), 3,3′-di-O-methylquercetin (4), 3,3′-di-O-methylquercetin-7-O-β-d-glucopyranoside (5), isorhamentin-3-O-β-d-rutinoside (6), 8-O-methylretusin (7), 8-O-methylretusin-7-O-β-d-glucopyranoside (8), salicylic acid (9), p-hydroxybenzoic acid (ferulic acid) (10), and 4-hydroxy-3-methoxy cinnamic acid (11). They were sorted as flavonols (1–6), soflavones (7 and 8), and phenolic acids (9–11). Among the compounds, flanools 1–4 revealed a strong antibacterial activity with minimum inhibitory concentration (MIC) values of 50–150 μg/mL, and median inhibitory concentration (IC₅₀) values of 26.8–125.1 μg/mL. The two isoflavones (7 and 8) showed moderate inhibitory activity on the test bacteria. Three phenolic acids (9, 10 and 11) showed strong antibacterial activity with IC₅₀ values of 28.1–149.7 μg/mL. Antifungal activities of the compounds were similar to their antibacterial activities. All these phenolic compounds showed significant antimicrobial activity with a broad spectrum as well as antioxidant activity based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and β-carotene-linoleic acid bleaching assays. In general, the flavonol aglycones with relatively low polarity exhibited stronger activities than the glycosides. The results suggest the potential of this plant as a source of functional food ingredients and provide support data for its utilization as forage as well.     

Antioxidant Properties of Phenolic Lignin Model Compounds

Antioxidant activities of phenolic lignin model compounds were determined by measurements of inhibition rate constants (k_inh) during inhibited peroxidation of styrene in chlorobenzene initiated by azobisisobutyrylnitrile with known rates of initiation (R_i). The number of peroxyl radicals trapped by each antioxidant, the stoichiometric factors (n), were determined by comparison with pentamethyl-hydroxychroman, PMHC, n = 2. Monomeric lignin models, 4-propylguaiacol (1), eugenol (2), isoeugenol (3), coniferyl alcohol (4), coniferyl aldehyde (5), and 4-allyl-2,6-dimethoxyphenol (6) were all more active antioxidants than the commercial inhibitor 2,6-di-tert-butyl-4-methylphenol (BHT). Two dimer models, bis(2-hydroxy-3-methoxyl-5-allylphenyl)methane (7) and 2,2′-dihydroxy-3,3′-dimethoxy-5,5′-dimethoxymethylbiphenyl (8) and a synthetic tetramer, bis[2-hydroxy-5-(2′-hydroxy-3′-methoxy-5′-methylbenzyl)-3-methoxyphenyl]methane (9) were more active antioxidants. The overall relative activity was tetramer > dimers > monomers > BHT. The stoichiometric factors of 1 to 6 ranged from 1.6 to 1.7 compared to PMHC. The n factors for 7, 8, and 9, showed an additive effect per phenolic hydroxyl. Phenolic groups in lignin may protect lignin-containing pulps and paper against damaging free radical peroxidation.     

新疆白麻药用成分的提取与表征

以新疆白麻Poacynum pictum(Schrenk)Baill叶为原料,采用溶剂萃取及色谱技术从新疆白麻叶中共分离并鉴定了11个化合物的结构,并通过理化常数、MS、1H NMR和13C NMR等现代波谱技术鉴定其化学结构,分别为羽扇醇棕榈酸酯(1)、异莨菪亭(2)、正十六烷酸(3)、正二十六烷酸(4)、β-谷甾醇(5)、槲皮素(6)、槲皮素-3-O-β-D-吡喃葡萄糖苷(7)、金丝桃苷(8)、Δ′-异戊烯-3-O-β-D-吡喃葡萄糖苷(9)、丁香树脂醇-β-D-吡喃葡萄糖苷(10)和蔗糖(11)。其中化合物2为首次从属中分离得到。     

Synthesis and Anti-Breast Cancer Evaluation of Novel N-(Guanidinyl)benzenesulfonamides

A series of 4-(substituted)-N-(guanidinyl)benzenesulfonamides bearing biologically active pyrazole, pyrimidine and pyridine moieties were prepared and evaluated for their anticancer activity against human tumor breast cell line (MCF7). These sulfonamides showed promising activity with IC₅₀ values ranging from 49.5 to 70.2 μM. The structure-activity relationship of the synthesized compounds was studied. Interestingly, it was found that the most potent compounds in this study were the corresponding 2-cyanoacrylate 3, 3-oxobutanoate 4, pyrazole 6, pyridine 9 and pyrazole 13. Compounds 7 and 8 are nearly as active as Doxorubicin as reference drug with (IC₅₀ values = 70.2, 68.1 μM), while compounds 5, 10 and 11 exhibited a moderate activity.     

5-Methoxy, 7-methylbenz[a]anthracene: Crystal Structure of a Planar Weak Carcinogen

Abstract

The crystal and molecular structure of 5-methoxy,7-methylbenz[a]anthracene has been determined by X-ray diffraction at room temperature to an R-index of 0.062 over 936 reflections. The molecule, the first methoxy-substituted methylbenz[a]anthracene to be analysed, is highly planar, with the carbon and oxygen atoms of substituents lying within 0.04 Å of the mean plane of the polycyclic skeleton. Carbon–oxygen bond lengths in the methoxy group are unequal at 1.372(7) and 1.426(9) Å and the C_aromatic–O bond makes dissimilar angles of 113.5(7) and 124.3(7)° at C(5). The shortest C–C bonds are C(5)–C(6) = 1.351(9) at the substituted K-region, C(8)–C(9) = 1.352(9), C(10)–C(11) = 1.362(9) Å, and C(3)–C(4) = 1.361(10) Å. In the unsubstituted bay region, the long beach bond C(13)–C(18) = 1.454(9) Å is flanked by beach bond angles C(12)–C(18)–C(13) = 121.2(6) and C(18)–C(13)–C(1) = 123.1(6)°.     

Structures of H3PO4/SiO2 catalysts and catalytic performance in the hydration of ethene

The hydration of ethene was carried out over H₃PO₄/SiO₂ having various amounts of H₃PO₄. The rate of the ethanol formation increased markedly with the increasing H₃PO₄ loadings, in particular above 60–70 wt%. By X-ray diffraction (XRD), and

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MAS NMR methods, it was revealed that various silicon phosphates were produced in the preparation of the catalysts. The structures of the phosphates depended on the H₃PO₄ loadings. It was suggested that Si(HPO₄)₂·H₂O species which formed at higher H₃PO₄ loadings were hydrolyzed to H₃PO₄ and SiO₂ during the course of the reaction, yielding the catalysts with high performance. The bulk phase of the H₃PO₄ was involved in the reaction.     

Synthesis of pyrazolo[4′,3′:5,6]pyrazino[2,3-c]pyrazoles and pyrazolo[4′,3′:5,6]pyrazino[2,3-d]pyrimidines and their application to polyester fibres

4-Nitroso-1-phenyl-3-methyl-5-aminopyrazole ( 1 ) was condensed with ethylcyanoacetate ( 2 ), malononitrile ( 4a ) and 2-cyanomethylbenzimidazole ( 4b ) to yield 6-hydroxy-5-cyano, 6-amino-5-cyano and 6-amino-5-(benzimidazol-2-yl)-3-methylpyrazolo [3,4-b]pyrazines 3, 5a and 5b , respectively. 5-Cyano-6-chloro derivative 6 obtained from 3 was converted to 3-aminopyrazolo[4′,3′:5,6]pyrazino[2,3-c]pyrazoles 8a and 8b by the treatment with hydrazin hydrate ( 7a ) and phenylhydrazine ( 7b ), respectively. Compound 5a was treated with formamide ( 9a ), urea ( 9b ) and thiourea ( 9c ) to give 4-aminopyrazolo[4′,3′:5,6]pyrazino[2′3′-d]pyrimidines 10a–10c. With refluxing acetic anhydride compounds 8a, 8b and 10a gave corresponding acetamido derivatives 8c, 8d and 10d. Compound 5a was treated with ethylorthoformate ( 11 ), acetic anhydride ( 12 ) or benzoylchloride ( 13 ) to give fused benzimidazopyrazolo[4′,3′:5,6]pyrazino[2′,3′-d]pyrimidines, viz., benzimidazol[1,2-c]pyrazolo[4,3-g]pteridines ( 14a–14c ). Some of the compounds 8, 10 and 14 were applied to polyester as disperse dyes and their fastness properties were studied.     

Lewis acid induced additions to unsaturated fatty compounds IV: Synthesis of cyclopentenones from Friedel- Crafts acylation products of unsaturated fatty compounds with α,β-unsaturated acyl chlorides

The ethylaluminium dichloride induced Friedel- Crafts acylation of unsaturated fatty compounds such as oleic acid ( 1a ), methyl oleate ( 1b ) and 10-undecenoic acid ( 9b ) and furthermore of 1-octene ( 9a ) with α,β-unsaturated acyl chlorides e.g. crotonic acid chloride ( 2a ) and acrylic acid chloride ( 2b ) gave the corresponding allyl vinyl ketones. Nazarov cyclizations of the acylation products 3a/4a, 3b/4b, 10a and 10b afforded the alkyl substituted 2-cyclopentenones 5a/6a, 5b/6b, 11a/12a and 11b/12b . Catalytic hydrogenation of 5b/6b and 11b/12b gave the respective saturated cyclic products 7b/8b and 13b/14b as diastereomeric mixtures.     

Counting and particle transmission efficiency of the aerodynamic particle sizer

The aerodynamic particle sizer (APS) measures the size distributions of particles with aerodynamic diameter between 0.5 and in real time. To provide accurate size distributions, the APS must measure both particle size and concentration correctly. The objective of this study was to characterize the counting efficiency of the APS as a function of particle size (0.8–), particle type (liquid or solid), and APS model number (3310 vs. 3321). For solid particles, counting efficiencies ranged between 85% and 99%. For liquid droplets, counting efficiencies progressively declined from 75% at 0.8-μm drops to 25% for 10-μm drops. Fluorometric wash tests indicated that transmission losses occur when larger droplets impact on the instrument's inner nozzle. However, transmission losses did not account entirely for the reduced droplet counting efficiencies, indicating that additional losses may have occurred downstream of the inner nozzle. Between instrument comparisons revealed that although multiple APSs report similar number concentrations, small deviations in particle sizing can produce substantial errors when number concentrations are converted to mass concentrations.     

Six- and seven-membered 1-oxa-4-aza-2-silacyclanes as possible correctors of adaptational mechanisms

The biological activity of eight 1-oxa-4-aza-2-silacyclanes with the OSiCH(2)N fragment including 6-membered 2-sila-5-morpholinones (1-3) and 4-acyl-2-silamorpholines (4-6)and previously unknown 7-membered derivatives of salicylic acid (7, 8) was studied. Compounds 1 and 3-6 show the certain antihypoxic action. Compounds 2 (40 mg/kg), 4 (20 mg/kg), 6 (40 mg/kg), 7 (20 mg/kg) and 8 (40 mg/kg) reduce the physical serviceability of intact animals. Compound 1 (20 mg/kg) influences the physical serviceability in a moderate-positive way on the background of chlorophos-poisoning. Compounds 5-8 displayed protective properties against chlorophos-poisoning at the LD(50) dose and compounds 2, 4, 5, 7 at the LD(100) dose. Influence of compounds 1 and 2 on the emotional-research behavior of mice was studied.     

NO reduction by H2 over perovskite-like mixed oxides

Perovskite-like mixed oxides

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(A′=Ce or Eu; B=Mn or Co) and La_0.8Sr_0.2BO_3+δ (B=Mn, Fe, Co or Ni) prepared by the amorphous citrate method were used as catalysts for NO reduction by hydrogen. XRD patterns showed a fully crystalline perovskitic structure only in the case of Ce- and Eu-substituted samples. The results suggest that the presence of structural defects is important for the activity of these catalysts, as shown by pretreatment under different atmospheres (He and O₂). La_0.9Ce_0.1CoO_3+δ was the most active of the mixed oxide catalysts investigated and its activity was influenced by the presence of both anion vacancies and Co²⁺ species. La_0.8Sr_0.2NiO_3+δ showed a particular catalytic behaviour, attributed to surface Ni reduction.