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A diverse array of 3,4-dihydro-2-pyridones 13 were produced utilizing the unique properties of solid-supported reactions to both drive the reactions to completion and isolate the desired products. The pyridones were synthesized in high purity by a simple sequence of novel steps commencing from an acetophenone-functionalized resin. The para-substituted acetophenone 9 could be anchored to the resin through either a sulfonamide or a carboxamide linkage. The sulfonamide resin 9a, which gave the best results, was treated with several aryl aldehydes and ethoxide to give a variety of chalcones 10a-k in excellent yield (82-99%) upon TFA cleavage. Addition of either methyl or allyl malonate and DBU to 10a-k afforded smoothly the Michael adducts 11a-j (70-99%) which were subsequently cyclized in one step employing acetic acid as a catalyst and several diverse amines to give pure 3,4-dihydro-2-pyridones 13a-p in moderate to excellent yields (30-98%).  相似文献   
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A red fluorescent dye of the oxonol class, bis-[1-(carboxymethyl)barbituric acid-(5)]-pentamethinoxonol, has been synthesized and, in the form of the succinimidyl active ester, has been applied to antibody labeling for application to flow cytometry and to imaging of tissue sections. The new dye, named CMOX (for carboxymethyloxonol), shows maximum excitation at 583 nm and emission at 611 nm, with a quantum yield of 0.2 in aqueous buffer and methanol. Antibodies labeled with the new dye show favorable brightness, photostability, and low levels of nonspecific binding.  相似文献   
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We consider a question of T. Jech and K. Prikry that asks if the existence of a precipitous filter implies the existence of a normal precipitous filter. The aim of this paper is to improve a result of Gitik (Israel J Math, 175:191?C219, 2010) and to show that measurable cardinals of a higher order rather than just measurable cardinals are necessary in order to have a model with a precipitous filter but without a normal one.  相似文献   
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We study the following game: each agent i chooses a lottery over nonnegative numbers whose expectation is equal to his budget b i . The agent with the highest realized outcome wins (and agents only care about winning). This game is motivated by various real-world settings where agents each choose a gamble and the primary goal is to come out ahead. Such settings include patent races, stock market competitions, and R&D tournaments. We show that there is a unique symmetric equilibrium when budgets are equal. We proceed to study and solve extensions, including settings where agents choose their budgets (at a cost) and where budgets are private information.  相似文献   
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In open, anonymous settings such as the Internet, agents can participate in a mechanism multiple times under different identities. A mechanism is false-name-proof if no agent ever benefits from participating more than once. Unfortunately, the design of false-name-proof mechanisms has been hindered by a variety of negative results. In this paper, we show how some of these negative results can be circumvented by making the realistic assumption that obtaining additional identities comes at a (potentially small) cost. We consider arbitrary such costs and apply our results within the context of a voting model with two alternatives.  相似文献   
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