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Synthesis of some dibenzodiazepinone derivatives as potent and m2-selective antimuscarinic compounds
Victor I. Cohen Biyun Jin Miriam S. Gitler Rosanna A. La De Cruz Waclaw J. Rzeszotarski Barry R. Zeeberg Jesse Baumgold Richard C. Reba 《Journal of heterocyclic chemistry》1994,31(4):787-791
Two series of 5-[[4-[4-(dialkylamino)butyl]-l-cyclohexyl]acetyl], and 5-[(dialkylamino)acyl]-10,11-dihydro-5H- dibenzo[b,e][1,4]diazepin-11-ones were synthesized as potential m2-selective ligands 1,2. Their affinity and selectivity for the muscarinic cholinergic receptor m-AChR subtypes were determined. Replacing a nitrogen with CH in the piperidine ring of 5-[[4-[4-(dialkylamino)butyl]-l-piperidinyl]acetyl]-10,11-dihydro-5H-dibenzo-[b,e][1,4]diazepin-11-ones 3 significantly altered the affinity and selectivity to the muscarinic receptor subtypes. 相似文献
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The role of different H-bonds in phases II, III, IV, and V of triammonium hydrogen disulfate, (NH(4)(+))(3)H(+)(SO(4)(2)(-))(2), has been studied by X-ray diffraction and (1)H solid-state MAS NMR. The proper space group for phase II is C2/c, for phases III and IV is P2/n, and for phase V is P onemacr;. The structures of phases III and IV seem to be the same. The hydrogen atom participating in the O(-)-H(+).O(-) H-bond in phase II of (NH(4)(+))(3)H(+)(SO(4)(2)(-))(2) at room temperature is split at two positions around the center of the crucial O(-)-H(+).O(-) H-bonding, joining two SO(4)(2)(-) tetrahedra. With decreasing temperature, it becomes localized at one of the oxygen atoms. Further cooling causes additional differentiation of possibly equivalent sulfate dimers. The NH(4)(+) ions participate mainly in bifurcated H-bonds with two oxygen atoms from sulfate anions. On cooling, the major contribution of the bifurcated H-bond becomes stronger, whereas the minor one becomes weaker. This is coupled with rotation of sulfate ions. In all the phases of (NH(4)(+))(3)H(+)(SO(4)(2)(-))(2), some additional, weak but significant, reflections are observed. They are located between the layers of the reciprocal lattice, suggesting possible modulation of the host (NH(4)(+))(3)H(+)(SO(4)(2)(-))(2) structure(s). According to (1)H MAS NMR obtained for phases II and III, the nature of the acidic proton disorder is dynamic, and localization of the proton takes place in a broader range of temperatures, as can be expected from the X-ray diffraction data. 相似文献
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Temperature and pressure sensitivities of the highly birefringent photonic crystal fiber with core asymmetry 总被引:2,自引:0,他引:2
T. Nasilowski T. Martynkien G. Statkiewicz M. Szpulak J. Olszewski G. Golojuch W. Urbanczyk J. Wojcik P. Mergo M. Makara F. Berghmans H. Thienpont 《Applied physics. B, Lasers and optics》2005,81(2-3):325-331
We investigated a particular design of a highly birefringent PCF with attractive features for pressure sensing applications. A plane-wave method together with the finite element method were used to numerically calculate phase and group modal birefringence, pressure and temperature sensitivities of our fiber. The simulation results together with the experiments demonstrate a considerable difference between a very high phase birefringence (B ∼ 10−3) and a very low negative group birefringence (G −10−3). Our fiber exhibits a low and positive temperature sensitivity (KT < 0.1 rad/(K⋅m)), and relatively high and negative mechanical (pressure) sensitivity (Kp ≤ −10 rad/(MPa⋅m)), which supports its possible use as a mechanical sensor that does not require any temperature compensation. 相似文献
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CP/MAS NMR spectra of solid trans-β-carotene were assigned, compared with crystallographic data and discussed in terms of molecular motion. 相似文献
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Two-, three- and four-arm, star-shaped poly(epsilon-caprolactone) and poly(D,L-lactide) homopolymers, and copolymers of epsilon-caprolactone with D,L-lactide were synthesized via ring-opening polymerization of cyclic esters in the presence of glycerol, penthaerythritol and poly(ethylene glycol) as initiators and stannous octoate as a catalyst. Thus obtained oligomers were successfully used in the synthesis of novel macromolecular prodrugs of norfloxacin. The structures of the polymers and prodrugs were elucidated by means of MALDI-TOF MS, NMR and IR studies. 相似文献
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T. Martynkien A. Anuszkiewicz G. Statkiewicz-Barabach J. Olszewski G. Golojuch M. Szczurowski W. Urbanczyk J. Wojcik P. Mergo M. Makara T. Nasilowski F. Berghmans H. Thienpont 《Applied physics. B, Lasers and optics》2009,94(4):635-640
We designed, fabricated, and characterized birefringent holey fibers with zero polarimetric sensitivity to temperature. The
sensitivity measurements were carried out in a wide spectral range of 0.68–1.55 μm in fibers with different hole and pitch
values and with birefringence induced by a pair of large holes adjacent to the core. Our results show that zero sensitivity
to temperature can be obtained at certain wavelengths for the bare fibers with properly adjusted geometrical parameters. Moreover,
the spectral measurements of the sensitivity to temperature are in good agreement with the modeling results for all the investigated
fibers. 相似文献
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J.P. Carvalho A. Anuszkiewicz G. Statkiewicz-Barabach J.M. Baptista O. Frazão P. Mergo J.L. Santos W. Urbanczyk 《Optics Communications》2012,285(3):264-268
In this work, we demonstrate the possibility of fabricating short-length long-period gratings and rocking filters in highly birefringent Photonic Crystal Fiber using a CO2 laser. In our experiments both kinds of gratings were made in the same Boron doped highly birefringent PCF using similar exposure parameters. We also present the sensing capabilities of both fabricated gratings to temperature, strain and hydrostatic pressure by interrogation of the wavelength shifts at different resonances. 相似文献
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The problem of critical load of an axially compressed open sandwich cylindrical shell with two straightlinear edges free is presented. Large angle of the shell sector, geometrical and physical symmetry of the facings are assumed. The simply formula for calculation critical stress in the shell is presented. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献