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A ring-cleaved sesquiterpene, named seco-laurokamurone, four laurane-type sesquiterpenes, laurepoxyene, 3β-hydroperoxyaplysin, 3α-hydroperoxy-3-epiaplysin, and 8,10-dibromoisoaplysin, one laurokamurane-type sesquiterpene, laurokamurene D, and one bisabolane-type sesquiterpene, (5S)-5-acetoxy-β-bisabolene, have been isolated from a re-collection of the red alga Laurencia okamurai Yamada, together with six other known sesquiterpenes. Their structures, including relative configuration, were elucidated by detailed analysis of spectroscopic data, and by comparison with data for related known compounds. In addition, on the basis of chemical conversions, degradation results, and biogenetic considerations, the absolute configurations of several of these compounds were also tentatively proposed. seco-Laurokamurone possesses an unprecedented carbon skeleton, formed from an oxidative cleavage of the laurokamurane skeleton, and laurokamurene D represents the fourth example of a laurokamurane-type sesquiterpene from a natural source. The in vitro antifungal activity of many of these compounds was evaluated against four fungi (Cryptococcus neoformans, Candida glabrata, Trichophyton rubrum, and Aspergillus fumigatus), as well as assessing cytotoxicity against HL-60 and A-549 human cancer cell lines. The compounds studied displayed moderate activities, relative to controls.

In this article, ultra-thin Al, Ag, Cu thin films with thickness d ~10nm are prepared by thermal evaporation, Ellipsometer and Spectrophotometer are used to measure Ψ, ∆, R and T of samples. Based on the characteristics of different metal materials, we choose proper physical model to analysis the dielectric function. Experimental results show that the method of Ellipsometer with transmittance data fitting can describe optical constants of ultra-thin metal films, and all the parameters of Ψ, ∆ and T show a good fitting result. Moreover, the reflection of samples simulated by MathCAD software using Fresnel coefficient equations also follows the measured reflectance data.

Nanoscale lead dioxide (nPbO

In this pilot study, a modified sampling protocol was evaluated for the detection of lead contamination and locating the source of lead release in a simulated premise plumbing system with one-, three- and seven-day stagnation for a total period of 475 days. Copper pipes, stainless steel taps and brass fittings were used to assemble the "lead-free" system. Sequential sampling using 100 mL was used to detect lead contamination while that using 50 mL was used to locate the lead source. Elevated lead levels, far exceeding the World Health Organization (WHO) guideline value of 10 µg · L(-1), persisted for as long as five months in the system. "Lead-free" brass fittings were identified as the source of lead contamination. Physical disturbances, such as renovation works, could cause short-term spikes in lead release. Orthophosphate was able to suppress total lead levels below 10 µg · L(-1), but caused "blue water" problems. When orthophosphate addition was ceased, total lead levels began to spike within one week, implying that a continuous supply of orthophosphate was required to control total lead levels. Occasional total lead spikes were observed in one-day stagnation samples throughout the course of the experiments.

Addition of orthophosphate has been commonly employed to suppress lead levels in drinking water. Its detailed mechanism and time required for it to become effective, however, have not been fully elucidated. In this study, we investigated the mechanistic role of orthophosphate as a corrosion inhibitor in controlling lead release from tetravalent lead corrosion product PbO(2) in chloraminated solutions, a system representing distribution networks experiencing disinfectant changeover from free chlorine to monochloramine. In all experiments with orthophosphate addition of at least 1 mg/L as P, peaking of soluble Pb(II) concentration within the first 24 h was observed before lead concentrations decreased and stabilized at levels lower than 15 μg/L. The variation of soluble Pb(II) concentration could be attributed to the dynamics between the rate of PbO(2) reductive dissolution, primarily induced by monochloramine decomposition, and that of chloropyromorphite (Pb(5)(PO(4))(3)Cl) precipitation, which did not occur until a critical supersaturation ratio of about 2.36 was reached in the solution. Our findings provide insights to how orthophosphate reduces lead levels under drinking water conditions and highlight the potential risk of short-term elevated lead concentrations. Intensive monitoring following the disinfectant changeover may be required to determine the overall lead exposure when using orthophosphate as a corrosion inhibitor.

Lead germanium telluride (Pb1-xGexTe), a pseudo-binary alloy of IV-VI narrow gap semiconductors PbTe and GeTe, is considered a potential mechanically robust high-index coating material. Pb1-xGexTe thin films were evaporated on silicon substrates from the ingots of single crystals using electron beam and resistance heating, respectively. The surface topographies and compositions of thin-films were characterized by using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX); the transmission spectra in a spectral range of 2.5~12 μm were also examined. Thin films demonstrated columnar microstructure; moreover, those evaporated using e-beam heating have much larger granular dimensions, in comparison with those using resistance heating. The measurement of transmittance reveals the advantage of perfect stoichiometry in e-beam evaporated thin films fails to improve optical properties. It can be deduced the scattering from the larger grains may impair the optical transparency. It can be concluded that electron beam evaporation is an optimum deposition choice.

A mechanically robust infrared high-index coating material is essential to the infrared interference coatings. Lead germanium telluride (Pb1-xGexTe) is a pseudo-binary alloy of IV-VI narrow gap semiconductors of PbTe and GeTe. In our investigation, the hardness and Young’s modulus of thin films of Pb1-xGexTe, which were deposited on silicon substrates using electron beam evaporation, were identified by means of nanoindentation measurement. It is demonstrated that layers of Pb1-xGexTe have greater hardness and Young’s modulus compared with those of PbTe. These mechanical behaviors of layers can be linked to a ferroelectric phase transition from a cubic paraelectric phase to a rhombohedral, ferroelectric phase. Moreover, the strength loss in the layers of Pb1-xGexTe can be also explained in light of strong localized elastic-strain fields in concentrated solid solutions.

The histamine H₄ receptor mediates several histamine-induced cellular functions of leukocytes, including cell migration and cytokine production. Recent studies suggest that histamine signaling through the histamine H₄ receptor can also have anti-pruritic and anti-nociceptive functions. 1-(7-(2-amino-6-(4-methylpiperazin-1-yl) pyrimidin-4-yl)-3, 4-dihdroisoquinolin-2(1H)-yl)-2-cyclopentylethanone (INCB38579) is a novel small molecule antagonist of the human and rodent histamine H₄ receptors with at least 80-fold selectivity over the human histamine H₁, H₂ and H₃ receptors, and has good pharmacokinetic properties in rats and mice. The compound is potent in inhibiting histamine binding to and signaling through the recombinant human, mouse and rat histamine H₄ receptors and blocks the histamine-induced migration of human and mouse dendritic cells, as well as the cell shape change and migration of human eosinophils. INCB38579 and histamine may have separate but overlapping binding sites on the human histamine H₄ receptor. This novel inhibitor is efficacious when evaluated in two previously established in vivo models for histamine H₄ receptor activity (histamine-induced itch in mice and carrageenan-induced acute inflammatory pain in rats). When examined in formalin-induced pain models, INCB38579 significantly reduces the sustained inflammatory pain experienced by rats and mice. A good correlation between the protein binding adjusted potency from in vitro studies and its analgesic effect in vivo was observed. These results suggest that INCB38579 can serve as a useful tool for pharmacologic characterization of the histamine H₄ receptor and further support the hypothesis that targeting the histamine H₄ receptor may provide new therapeutic agents for various chronic inflammatory diseases, including inflammatory pain.

laminated composites on silicon or magnesium oxide substrates. The magnetoelectric voltage coefficient is calculated as function of interface coupling factor k, volume ratio of piezoelectrics to piezomagnetic, and volume ratio of substrates to composite. It was found that the magnetoelectric voltage coefficient decreases as the interface coupling factor k weakens, while the volume ratio of piezoelectrics to piezomagnetic vmax shifts to lead-rich compositions. The magnetoelectric voltage coefficient of laminated composites decreases sharply with increasing substrates thickness ratio, which shows strong substrate clamping effect to the magnetoelectric composite.

A new polyacetylenic fatty acid, (8E,12Z,15Z)-10-hydroxy-8,12,15-octadecatrien-4,6-diynoic acid (1), together with five known metabolites, including two linear diterpenes (3 and 4) and three sterols (5–7), has been isolated from the Chinese green alga Caulerpa racemosa. Its structure was determined on the basis of extensive spectroscopic analysis. Compound 1 represents the first example of polyacetylenic lipids from marine algae up to now, while compound 4 is characterized for the first time in the Caulerpaceae. Furthermore, the chemotaxonomic significance of these compounds was also summarized.

The treatment of abdominal wall neoplasm continues to present a challenging problem because it is not easy to repair the giant defect which is resulted from extensive tumor excision. Some techniques and materials have been reported, but most report a certain technique or material for abdominal wall reconstruction. Therefore, we retrospectively reviewed the treatment of such patients in our department and assessed the reconstruction algorithm in such a situation. We studied 27 patients undergoing immediate abdominal wall reconstruction between 1999 and 2008 who sought care for major defects after extensive tumor excision of malignancy. We categorized the defects into three types: type I, defects involving only the loss of skin (15 cases); type II, myofascial defects with intact skin coverage (6 cases); and type III, myofascial defects without skin coverage (6 cases). Different techniques and materials were used. Postoperative morbidities, sign of herniation, and other follow-up data were recorded. The immediate abdominal wall reconstruction was successful in all patients. There was no severe morbidity after the operation. Only one patient developed hernia. Most type I defects can be corrected with primary suture. For type II defects, a prosthetic or biological mesh, or alternatively an autologous fascial substitute, may be used. For type III defects, the resulting full-thickness defect will require a myocutaneous flap, such as the tensor fascia lata flap, with or without a mesh for abdominal wall reconstruction. Human acellular dermal matrix, a biological mesh, is an ideal alternative for synthetic mesh, especially in situations of infection or contamination.

Barium molybdate (BaMoO 4 ) thin films with scheelite-structure were prepared on different substrates (ITO conducting glass; molybdenum; Au-coated Si) via electro-deposition technology in ethylene glycol at room temperature. Crystal structure of the prepared films was determined through X-ray diffraction (XRD) technique. Surface morphology of the as-deposited films was investigated by atomic force microscope (AFM). Experimental results reveal that the BaMoO4 thin film with scheelite-structure prepared under the optimal condition is compact and well-crystallized, and the grains present pyramid shape. The influence of current density and solution concentration on growth rate of BaMoO4 thin film was predominantly discussed.

CaWO 4 thin films were successfully prepared on glass and Si(100) substrates by chemical solution processing (CSP). The thin films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and atomic force microscopy (AFM), respectively. The results indicate that the CaWO 4 thin film crystallize from an inorganic amorphous phase directly at 350°C. The grain size and the surface roughness of the CaWO 4 thin film can be modulated by annealing processing. Microwave radiation method is helpful to improve the microstructure quality and the chemical homogeneity of the as-prepared thin films. The photoluminescence (PL) spectra of the thin film was positioned in a blue shifted region about 414 nm compared with emission at 440 nm of CaWO 4 crystals, which indicated the optical band gap widening phenomena induced by the quantum size effect.

To observe the clinical curative effect of Chinese herbal medicine combined with acitretin capsule in treating psoriasis of blood-heat syndrome (P-BH).Eighty patients of P-BH were randomly assigned to two groups, 39 in Group A and 41 in Group B. Both was treated with Chinese herbal medicines for clearing heat, cooling blood and removing toxic substance, and acitretin capsule was given to Group A additionally, with 8 weeks as one therapeutic course. The clinical curative effect was compared between groups, and the change of psoriasis activity severe index (PASI) scores before and after treatment was observed.The total effective rate in Group A was 84.2% and that in Group B 68.2%, also showing significance between groups (P0.01). PASI score lowered significantly after treatment in both groups, showing statistical significance (P0.01), but no significant difference between groups. Little adverse reaction was found in Group B, while in Group A, the adverse reaction was of even milder degree, which could be alleviated by adjusting the herbal medicine and symptomatic treatment administration.The effect of Chinese herbal medicine combined with acitretin capsule was superior to Chinese herbal medicine alone in treating P-BH, but the adverse reaction of acitretin capsule could be alleviated by adjusting the herbs used. However, the result is waiting to be verified further by larger samples.

Stoichiometric CaMoO4 thin film was successfully fabricated based on chemical solution processing. The thin films were deposited on Si(100) substrates by means of the spin-coating technique. X-ray diffraction reveals that the CaMoO4 thin film prepared are pure and well crystalline thin films. Atom Force Microscope photographs indicate that the film prepared possesses a homogeneous and dense surface morphology. The average grain size of the films was 40–50 nm, and the root-mean-square (RMS) of the surface roughness and the average surface roughness of the film measured were 2.161 nm and 1.726 nm respectively. The photoluminescent properties of calcium molybdate thin film under ultraviolet light excitation were systematically measured from 12 K to room temperature and a green emission band of the films were observed. The results of present work confirm that the chemical solution processing is a promising technology on the fabrication of CaMoO4 thin film.

Lead-free piezoelectric ceramics, Bi 0.5 (Na 1− x − y K x Ag y ) 0.5 TiO 3 , were prepared by a solid-state reaction process, and the dielectric property and phase structure of Bi 0.5 (Na 1− x − y K x Ag y ) 0.5 TiO 3 ceramics were investigated. XRD patterns show that the MPB of BNKAT( x /0.02) system ceramics lies in the composition range of 0.175 ≤ x ≤ 0.20. The relative permittivity ɛ r and loss tangent tan δ vary with the K + content and show a strong temperature- and frequency-dependent behavior in the temperature range measured. The K + content strongly influences the transition temperature from ferroelectric to anti-ferroelectric phase. In the high-temperature range, the thermal variation of the relative permittivity at various frequencies is well described by the law (1/ ɛ r ) − (1/ ɛ r,m ) = C( T − T m ) α . Such a relaxation behavior may be ascribed to the cations disorder of Na + , K + , Ag + , Bi 3+ at A-site.

Lanthanum-doped lead titanate [(Pb0.9,La0.1)TiO3, PLT10] ferroelectric thin films were grown on Si(100) and Pt/Ti/SiO2/Si(100) substrates by radio frequency (RF) magnetron sputtering. The crystalline properties of PLT10 films were studied by X-ray diffractometry (XRD). Photolithographic technique was applied to fabricate the interdigital electrodes on PLT10 thin films on Si(100) substrates. The dielectric properties of PLT10 thin films with different electrodes were measured. At room temperature and 1 kHz testing frequency, the dielectric constant of the PLT10 thin film with interdigital electrodes is 386. The dielectric constant of the PLT10 thin film fabricated under the same technological conditions with parallel plate electrodes structure is 365, while the dielectric constant and loss of the PLT10 thin film with interdigital electrodes are decreased faster than those of the film with parallel plate electrodes with increasing frequency. This is because more influences of interface state are introduced due to the interdigital electrode configuration.

Ba1−x Sr x TiO3 (BST) thin films were prepared on the substrate of Pt/Ti/SiO2/Si by using novel sol–gel process through carbonates. The surface morphology and domain contrast of the films were investigated by atomic force microscopy (AFM), and the domain structures of the BST film were observed when AFM were operated in piezoelectric force microscopic (PFM) analysis and in the friction mode (FFM). The ferroelectric properties of the films were also investigated. It is shown that BST films obtained by the new sol–gel process through carbonates exhibit good properties.

Magnesium oxalate hollow nanostructures and cobaltous hydroxide nanorods have been synthesized successfully by one-step solid-state chemical reaction at low-heating temperature. Magnesium oxalate hollow nanospheres were obtained via directly grinding magnesium acetate and oxalic acid. Cobaltous hydroxide nanorods were also fabricated by means of a suitable surfactant to modify the solid-state reaction. The as-prepared samples were characterized by X-ray diffraction, TEM, and SEM.

An efficient asymmetric synthesis of conformationally constrained (2S,3S)-piperidinedicarboxylic acid derivatives starting from L-aspartic acid β-tert-butyl ester and 3-chloro-2-(chloromethyl)-1-propene is described. The key steps involve N-alkylation of the aspartic acid ester followed by a stereoselective enolate intramolecular cyclization (>95:5 dr). Various synthetic strategies were explored to achieve the cyclopropanation of the resulting olefin, including the Simmons-Smith reaction and palladium-catalyzed cyclopropanation.

The design, synthesis, evaluation, and identification of a novel class of (6S,7S)-N-hydroxy-6-carboxamide-5-azaspiro[2.5]octane-7-carboxamides as the first potent and selective inhibitors of human epidermal growth factor receptor-2 (HER-2) sheddase is described. Several compounds were identified that possess excellent pharmacodynamic and pharmacokinetic properties and were shown to decrease tumor size, cleaved HER-2 extracellular domain plasma levels, and potentiate the effects of the humanized anti-HER-2 monoclonal antibody (trastuzumab) in vivo in a HER-2 overexpressing cancer murine xenograft model.

This study aimed to investigate the protective effects and the mechanisms underlying these effects of isoflurane preconditioning in the delayed phase of myocardial ischemia-reperfusion injury. We randomly divided 30 healthy male New Zealand white rabbits into three groups with 10 rabbits in each group as follows: sham operation group (C group), ischemia-reperfusion group (I/R group), and 2.0% isoflurane preconditioning group (S group). Rabbits in the C group received thoracotomy for 160 min. Rabbits in the I/R group underwent left coronary artery occlusion for 40 min and reperfusion for 120 min. Rabbits in the S group received inhalation of 2.0% isoflurane and 100% oxygen for 2 h; after 24 h, rabbits in this group received the same treatment as that administered to rabbits in the I/R group. We examined the tumor necrosis factor alpha (TNF-α) levels in each group 20 min before occlusion of the left coronary, 20 and 40 min after occlusion of the left coronary artery, and 1 and 2 h after myocardial reperfusion. After reperfusion, immunoblotting was used to measure the myocardial caspase-3 expression levels, and the infarct size was measured using Evans blue and tetrazolium chloride staining. The levels of TNF-α and caspase-3 were lower in the S group than in the I/R group, and the myocardial infarct size decreased in the S group. Thus, isoflurane preconditioning in the delayed phase exerted protective effects by decreasing the myocardial caspase-3 expression and TNF-α production in a rabbit model of ischemia-reperfusion injury.

A modified solid on solid (SOS) model for the simulation of epitaxial growth of ABO3 type thin films through cell-diffusion on the surface developed by using Monte Carlo (MC) method is presented in this paper. Two diffusion active energy parameters were assumed to be 0.6 eV, which is the diffusion potential barrier on the surface, and 0.8 eV, which is the diffusion potential barrier when a basic unit separates from other units. The results show that the ABO3 expitaxial thin films grow with layer by layer mode at the conditions of higher temperature and lower deposition rate. And with the conditions of lower temperature and higher deposition rate, it is the island mode; and even with same growth mode, the morphology pictures of thin films show that the growth process is different. The shape, size and number of islands are not only related to the growth temperature, but also related to the deposition rate. And the compact initial islands are more likely to develop into smooth thin films with layer-...

Overexpression and activating mutations of ErbB family members have been implicated in the development and progression of a variety of tumor types. Cleavage of the HER2 receptor by an as yet unidentified ectodomain sheddase has been shown to liberate the HER2 extracellular domain (ECD) leaving a fragment with constitutive kinase activity that can provide ligand-independent growth and survival signals to the cell. This process is clinically relevant since HER2 ECD serum levels in metastatic breast cancer patients are associated with a poorer prognosis. Thus, inhibition of the HER2 sheddase may provide a novel therapeutic approach for breast cancer. We describe the use of transcriptional profiling, pharmacological and in vitro approaches to identify the major source of HER2 sheddase activity. Real-time PCR was used to identify those ADAM family members which were expressed in HER2 shedding cell lines. siRNAs that selectively inhibited ADAM10 expression reduced HER2 shedding. In addition, we profiled over 1000 small molecules for in vitro inhibition of a panel of ADAM and MMP proteins; a positive correlation was observed only between ADAM10 inhibition and reduction of HER2 ECD shedding in a cell based assay. Finally, in vitro studies demonstrate that in combination with low doses of Herceptin, selective ADAM10 inhibitors decrease proliferation in HER2 overexpressing cell lines while inhibitors, that do not inhibit ADAM10, have no impact. These results are consistent with ADAM10 being a major determinant of HER2 shedding, the inhibition of which, may provide a novel therapeutic approach for treating a variety of cancers with active HER2 signaling.

A simple and facilitate method was reported to synthesize zinc oxide and lead oxide nanorods. Two metal oxides nanorods were directly obtained from grinding solid metallic salts and sodium hydroxide in agate mortar with the assistance of a suitable surfactant in only one step, which is different from the results of hydroxides in solution. The as-prepared products were characterized by XRD, TEM and SEM. An explanation describing possible mechanism for the rod-formation is given.

Phenoxathiin cation radical perchlorate (PO.+ClO4(-)) added stereospecifically to cyclopentene, cyclohexene, cycloheptene, and 1,5-cyclooctadiene to give 1,2-bis(5-phenoxathiiniumyl)cycloalkane diperchlorates (4-7) in good yield. The diaxial configuration of the PO+ groups was confirmed with X-ray crystallography. Unlike additions of thianthrene cation radical perchlorate (Th.+ClO4(-)) to these cycloalkenes, no evidence for formation of monoadducts was found in the reactions of PO.+ClO4(-). This difference is discussed. Addition of Th.+ClO4(-) to five trans alkenes (2-butene, 2-pentene, 4-methyl-2-pentene, 3-octene, 5-decene) and four cis alkenes (2-pentene, 2-hexene, 2-heptene, 5-decene) gave in each case a mixture of mono- and bisadducts in which the configuration of the alkene was retained. Thus, cis alkenes gave erythro monoadducts and threo bisadducts, whereas trans alkenes gave threo monoadducts and erythro bisadducts. In these additions to alkenes, cis alkenes gave predominantly bisadducts, while trans alkenes (except for trans-2-butene) gave predominantly monoadducts. This difference is explained. 1,2-Bis(5-phenoxathiiniumyl)cycloalkanes (4-7) and 1,2-bis(5-thianthreniumyl)cycloalkanes underwent fast elimination reactions on activated alumina forming, respectively, 1-(5-phenoxathiiniumyl)cycloalkenes (8-11) and 1-(5-thianthreniumyl)cycloalkenes (12-16). Among adducts of Th.+ClO4(-) and alkenes, monoadducts underwent fast ring opening on alumina to give (5-thianthreniumyl)alkenes, while bisadducts underwent fast eliminations of H+ and thianthrene (Th) to give (5-thianthreniumyl)alkenes also. Ring opening of monoadducts was a stereospecific reaction in which the configuration of the original alkene was retained. Thus, erythro monoadducts (from cis alkenes) gave (E)-(5-thianthreniumyl)alkenes and threo monoadducts (from trans alkenes) gave (Z)-(5-thianthreniumyl)alkenes. Among bisadducts, elimination of a proton and Th occurred and was more complex, giving both (E)- and (Z)-(5-thianthreniumyl)alkenes. These results are explained. Configurations of adducts and (5-thianthreniumyl)alkenes were deduced with the aid of X-ray crystallography and (1)H and (13)C NMR spectroscopy. In the NMR spectra of (E)- and (Z)-(5-thianthreniumyl)alkenes, the alkenyl proton of Z isomers always appeared at a lower field (0.8-1.0 ppm) than that of E isomers.

Reactions between 5-(aryl)thianthrenium bromides (1a–e) with aryl (Ar) groups phenyl (a), p-tolyl (b), p-anisyl (c), p-chlorophenyl (d) and p-bromophenyl (e) and sodium aryl oxides (7a–c, Ar′ONa, Ar′ = phenyl, p-tolyl and p-chlorophenyl) were carried out in acetonitrile at 80 °C. Results are compared with those of earlier reactions of 1a–e with corresponding sodium aryl thiolates (Ar′SNa). In contrast with the thiolate reactions, those with 7a–c were too slow at room temperature to be useful. Reactions of 1a–c at 80 °C gave small amounts of benzene and toluene from 1a and b, small amounts of diaryl ethers ArOAr′ (9) and thianthrene (Th) and large amounts (90–97%) of 2-(ArS)-2′-(Ar′O)diphenyl sulfide (10). Compared with reactions of 1a–c, those of 1d and e gave larger amounts (10–17%) of 9, lesser amounts (25–30%) of 10 and substantial amounts (42–55%) of 2-[4-(Ar′O)-ArS]-2′-(Ar′O)diphenyl sulfide (12). Small amounts of 1,4-di(Ar′O)benzene (11) were also obtained from reactions of 1d and e. Formation of 11 and 12 is preceded by replacement of halogen by Ar′O−. Structures of products 10 and 12 were deduced by comparison with earlier products from thiolate reactions, elemental analyses, mass spectrometry molecular masses and, in the case of 10, the crystal structure of 10d. It is proposed that products 9–12 are formed by nucleophilic reactions of Ar′O− at ipso positions in 1. Copyright © 2003 John Wiley & Sons, Ltd.