A novel indomethacin ester prodrug, 2-[N-[3-(3-(piperidinomethyl)phenoxy)propyl]carbamoylmethylthio ]ethyl 1-(p-chlorobenzoyl)-5-methoxy-2-methylindole-3-acetate (1) was prepared from a new histamine H2-receptor antagonist, N-[3-(3-(piperidinomethyl)phenoxy)propyl]-2-(2-hydroxyethylthio )acetamide (2) and indomethacin (3). The compound 1 was shown to be essentially similar to 3 in its antiinflammatory action and to almost completely inhibit carrageenin-induced hind-paw edema in the rat at a very high dose of 230 mg/kg (280 mumol/kg), which is comparable to that of 100 mg/kg (280 mumol/kg) of 3, without producing gastric lesions. On a molar basis, the acute gastric lesioning properties of 1 were near one-hundred times less than those of 3, resulting in over a twenty-fold improvement in the ratio of antiedema activity to ulcerogenicity. The effect of the co-administration of histamine H2-receptor antagonists on antiedema activity and ulcerogenicity caused by 3 is also discussed. 相似文献
Expeditious synthesis of (R)-bicalutamide (1), a synthetic antiandrogen, from enantiopure 2-methylpropane-1,2,3-triol monobenzyl ether (4) was achieved. An engineered Bacillus subtilis epoxide hydrolase worked enantioselectively on the racemic epoxide (7) to provide the above starting material in highly enantiomerically enriched state. 相似文献
The directional properties of bottlenose dolphin clicks, burst-pulse, and whistle signals were measured using a five element array, at horizontal angles of 0°, 45°, 90°, 135°, and 180° relative to a dolphin stationed on an underwater biteplate. Clicks and burst-pulse signals were highly directional with directivity indices of ~11 dB for both signal types. Higher frequencies and higher amplitudes dominated the forward, on-axis sound field. A similar result was found with whistles, where higher frequency harmonics had greater directivity indices than lower frequency harmonics. The results suggest the directional properties of these signals not only provide enhanced information to the sound producer (as in echolocation) but can provide valuable information to conspecific listeners during group coordination and socialization. 相似文献
A macroporous silica-based supramolecular recognition absorbent (Calix[4]?+?Dodecanol)/SiO2?CP, was prepared by successive impregnation and fixing the 1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-Calix[4]arene (Calix[4]arene-R14) and its molecule modifier 1-Dodecanol onto SiO2 silica-based polymer support. The characterization of (Calix[4]?+?Dodecanol)/SiO2?CP was examined by thermal gravimetry and differential thermal analysis and electron probe microanalysis. Relatively large separation factors of Cs and other metal ions (??Cs/Mn+) above 60 were obtained in the presence of 3?M HNO3. The adsorption data of Cs(I) fitted well with Langmuir isotherm and the maximum adsorption capacity was estimated to be 0.19?mmol?g?1. The Cs(I) in 3?M HNO3 were also effectively adsorption on (Calix[4]?+?Dodecanol)/SiO2?CP in the column operation, and the loaded Cs(I) was successfully eluted with an eluent of H2O. The column packed with (Calix[4]?+?Dodecanol)/SiO2?CP had excellent reusability after three cycles. 相似文献
Small-angle x-ray scattering measurements using a brilliant x-ray source revealed nanometer sized liquid droplets in a mist formed by ultrasonic atomization. Ultrasonic atomization of ethanol-water mixtures produced a combination of water-rich droplets of micrometer order and ethanol-rich droplets as small as 1 nm, which is 10(-3) times smaller than the predicted size. These sizes were also obtained for mists generated from the pure liquids. These results will help to clarify the mechanism of "ultrasonic ethanol separation," which has the potential to become an alternative to distillation. 相似文献
Cyclic isothioureas 1, 2, 3, and 4 were synthesized through a four-step procedure from the corresponding ortho-bromoanilines 10 via Pd- or Cu-catalyzed cyclization–benzothiazole formation. Nonbenzo analogues 7, 8, and 9 were synthesized by a condensation reaction of cyclic thioureas 15 and α-bromoacetophenones 14. Investigations of the acylation reactions of 1-phenylethanol with acid anhydrides in the presence of these cyclic isothiourea catalysts revealed their structure–activity relationships. Remarkable electronic effects resulting from substituent(s) on a benzo or phenyl moiety and the influence of the size of the annulating ring were observed. Introduction of an electron-donating substituent(s) enhanced the reaction rate. A few substitution effects on chiral catalysts of type 3 and 7 were also studied. 相似文献
Development of artificial tissues providing the proper geometrical, mechanical, and environmental cues for cells is highly coveted in the field of tissue engineering. Recently, microfabrication strategies in combination with other chemistries have been utilized to capture the architectural complexity of intricate organs, such as the liver, in in vitro platforms. Here it is shown that a biofunctionalized poly (ethylene glycol) (PEG) hydrogel scaffold, fabricated using a sphere‐template, facilitates hepatic sheet formation that follows the microscale patterns of the scaffold surface. The design takes advantage of the excellent diffusion properties of porous, uniform 3D hydrogel platforms, and the enhanced‐cell–extracellular matrix interaction with the display of conjugated collagen type I, which in turn elicits favorable Huh‐7.5 response. Collectively, the experimental findings and corresponding simulations demonstrate the importance of biofunctionalized porous scaffolds and indicate that the microscaffold shows promise in liver tissue engineering applications and provides distinct advantages over current cell sheet and hepatocyte spheroid technologies.