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41.
We report herein a simple and efficient two-step synthetic approach to new 2-trichloromethylquinazolines possessing a variously substituted sulfonamide group at position 4 used to prepare new quinazolines with antiparasitic properties. Thus, an original series of 20 derivatives was synthesized, which proved to be less-toxic than previously synthesized hits on the human HepG2 cell line, but did not display significant antiplasmodial activity. A brief Structure-Activity Relationship (SAR) evaluation shows that a more restricted conformational freedom is probably necessary for providing antiplasmodial activity.  相似文献   
42.
The stilbene derivative 1,2,3‐trimethoxy‐4‐[(E)‐2‐phenylvinyl]benzene, C17H18O3, (I), and its homocoupling co‐product (E,E)‐1,4‐bis(2,3,4‐trimethoxyphenyl)buta‐1,3‐diene, C22H26O6, (II), both have double bonds in trans conformations in their conjugated linkages. In the structure of stilbene (I), the aromatic rings deviate significantly from coplanarity, in contrast with coproduct (II), the core of which is rigorously planar. The deviation in stilbene (I) seems to be driven by intermolecular electrostatic interactions. Diene (II) sits on a crystallographic inversion centre, which bisects the conjugated linkage.  相似文献   
43.
A one-pot synthesis of novel poly-substituted phenanthrenes is described in this article through a Suzuki-Miyaura cross-coupling followed by a Dieckmann-Thorpe ring closure under microwave irradiation. The selection of the appropriate starting materials allowed us to introduce diversity on various positions of the phenanthrene ring system.  相似文献   
44.
A microencapsulated flame retardant with a melamine‐formaldehyde shell was prepared by in situ polymerization, then incorporated into an iPP matrix with a coupling agent to manufacture multifilament yarns by melt spinning. The influence of the post‐treatment on the resulted microcapsules with an alcoholic solution was also studied. The spinnability of these formulations based on the interface characterization from contact angle measurements, tensile test and thermal characterizations was explored to determine the maximum draw ratio (DR) to apply. Finally, knitted fabrics were processed from multifilaments, and their flame‐retardant properties were evaluated by performing fire tests according to the FMVSS 302 and Din 4102 part B experiments. The different mechanical and thermal behaviors were discussed in terms of the influence of the DR and the post‐treatment applied on fibers during the spinning process and during the recovery of the microcapsules, respectively. The results showed that it was possible to obtain multifilament yarns with a DR of 4, but the best properties were obtained with a DR of 3 and for un‐treated microcapsules. Furthermore, the samples containing un‐treated microcapsules reach a B rating at the FMVSS test with a fast flame progression and a very low duration of burning. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
45.
It is shown that by low frequency measurements in hydrophilic polymers only one state of water is observed. Water behave as a classical plasticizer and ice melting in polymer is similar to ice melting in binary simple mixture. The non crystallizable water in these systems is explained by the Tg regulation effect. In oriented swollen polymers, only one state of water is observed in the time scale ∼ 1/ωq = 10−5 s by deuterium NMR. This technique gives information on the mean orientation of D2O molecules in the oriented polymer and on the fraction of mobile water molecules. The concept of bound and unbound water is not relevant for explaining the DSC and D-NMR results.  相似文献   
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The present study discusses the well-known 5-HT7/5-HT1A selectivity issue through a new series of phenylpyrrole derivatives. The first hits emerged from a virtual screening performed on a chemolibrary. Further study led to an optimization of a preliminary 5-HT7 pharmacophore model. The importance of each pharmacophoric feature is confirmed, but these characteristics have to be coupled to geometric constraints in order to achieve a 5-HT7 selectivity. Indeed, 5-HT1A affinity probably arises from extended conformations, whereas a bent one appears to be best suited for 5-HT7 selectivity.  相似文献   
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The crystal structure of 7‐nitro‐1H‐indazole, C7H5N3O2, an inhibitor of nitric oxide synthase, shows the existence of an intramolecular hydrogen bond between an O atom of the nitro group and the NH group of the indazole ring. The crystal packing consists of intermolecular hydrogen bonding and indazole?indazole interactions.  相似文献   
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