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101.
Chang JC Tomlinson ID Warnement MR Iwamoto H DeFelice LJ Blakely RD Rosenthal SJ 《Journal of the American Chemical Society》2011,133(44):17528-17531
The serotonin (5-hydroxytryptamine, 5-HT) transporter (SERT) protein plays a central role in terminating 5-HT neurotransmission and is the most important therapeutic target for the treatment of major depression and anxiety disorders. We report an innovative, versatile, and target-selective quantum dot (QD) labeling approach for SERT in single Xenopus oocytes that can be adopted as a drug-screening platform. Our labeling approach employs a custom-made, QD-tagged indoleamine derivative ligand, IDT318, that is structurally similar to 5-HT and accesses the primary binding site with enhanced human SERT selectivity. Incubating QD-labeled oocytes with paroxetine (Paxil), a high-affinity SERT-specific inhibitor, showed a concentration- and time-dependent decrease in QD fluorescence, demonstrating the utility of our approach for the identification of SERT modulators. Furthermore, with the development of ligands aimed at other pharmacologically relevant targets, our approach may potentially form the basis for a multitarget drug discovery platform. 相似文献
102.
An online citrate and Ca(2+) sensing system based on sequential injection analysis (SIA) is developed as a safety module for hemodialysis. Host 1 displays high affinity towards citrate, and was selected for this study owing to its unique structural features. The o-aminomethylphenylboronic moiety can effectively interact with the α-hydroxycarboxylate moiety of citrate and the remaining two guanidiniums may further stabilize the complex via hydrogen bonds. Fura-2 chelates to Ca(2+) with a high selectivity and affinity and was utilized in this study for Ca(2+) measurements. The citrate sensing chemistry via an indicator displacement assay is orthogonal to the Ca(2+) sensing chemistry, and the use of sophisticated chemometrics is not required for data analysis. The citrate and Ca(2+) concentrations in dialysate samples are measured with the developed SIA system. The obtained citrate concentrations were verified via a commercially available enzymatic assay and an NMR method, respectively, while the Ca(2+) concentrations were verified via atomic absorption. 相似文献
103.
Chan J Burke BJ Baucom K Hansen K Bio MM DiVirgilio E Faul M Murry J 《The Journal of organic chemistry》2011,76(6):1767-1774
Two new, reliable syntheses of a pyrido[2,3-d]-pyrimidine inhibitor of the CXCR3 receptor are described. A nine-step synthesis of the CXCR3 inhibitor (1) from 2-aminonicotinic acid was demonstrated on a multikilogram scale and incorporates a classic resolution to deliver the enantioenriched active pharmaceutical ingredient (API). A second synthesis of the CXCR3 inhibitor starts from (+)-(D)-Boc alanine and 2-chloronicotinic acid and utilizes a Goldberg coupling. This second synthesis, performed on a gram scale, intersects the former route at a common intermediate thereby completing a formal synthesis of the enantioenriched API in higher overall yield without the need for a resolution. 相似文献
104.
Kumari H Kline SR Schuster NJ Atwood JL 《Chemical communications (Cambridge, England)》2011,47(45):12298-12300
The stability of copper-seamed C-alkylpyrogallol[4]arene hexamers with varying chain lengths in solution has been studied using small-angle neutron scattering (SANS). The progression in diameter of spherical capsules with increasing alkyl chain lengths of copper-seamed hexamers in solution suggests both robustness as well as a close correlation between the solid phase and solution phase structures. 相似文献
105.
Tian J Ma S Thallapally PK Fowler D McGrail BP Atwood JL 《Chemical communications (Cambridge, England)》2011,47(27):7626-7628
Cucurbit[7]uril (CB[7]), in its amorphous solid state, shows one of the highest CO(2) sorption capacities among known organic porous materials at 298 K and 0.1 and 1 bar. In addition to the highest CO(2) capacity, CB[7] also shows remarkable selectivity of CO(2) over N(2) and CH(4). These properties, along with the existence of readily available precursors, indicate amorphous CB[7] might find applications in recycling CO(2) particularly considering the easy synthesis and potentially low manufacturing costs. 相似文献
106.
Tian J Thallapally P Liu J Exarhos GJ Atwood JL 《Chemical communications (Cambridge, England)》2011,47(2):701-703
A well-known organic host, tris-o-phenylenedioxycyclotriphosphazene, exists in two polymorphic guest-free forms: the thermodynamic nonporous high-density phase and the kinetic nanoporous low-density phase. Simple pressurization of the high density phase with CO(2) brings a solid-state transformation to the low density phase, resulting in significant expansion of the crystal volume by 23%. 相似文献
107.
Martin AD Boulos RA Iyer KS Sobolev AN Bond CS Atwood JL Dalgarno SJ Raston CL 《Chemical communications (Cambridge, England)》2011,47(35):9882-9884
Hirshfeld surface analysis of the 'ordered' inner phase of the molecular capsule complex, [(chloroform)(6)@C-n-butylpyrogallol[4]arene)(6)], provides insight into the intermolecular contacts and orientation of the solvent molecules. Molecular simulations show that adding two or three hydrogen molecules to the six solvent molecules is energetically favoured, and this correlates with NMR studies. 相似文献
108.
Keld Lars Bak Jerry Boatz Jack Simons 《International journal of quantum chemistry》1991,40(3):361-378
The first-order geometrical response equations for a state-averaged multiconfigurational self-consistent field (SA -MCSCF ) calculation are derived. This derivation is carried through from first principles to final working equations suited for computer implementation. The final equations are expressed such that the energies and wave functions must be known only for the internal SA -MCSCF states. In the derivation, the special but important case where two or more internal states have equal weighting factors is treated in a manner fully consistent with all other cases. Except for introducing extra equations that are straightforward to solve, the case where two or more internal states have equal weighting factors introduces no new complications. 相似文献
109.
110.
Jerry S. Kelly Wulf Gaertner Prasanta J. Pattanaik Maurice Salles 《Journal of Elasticity》1989,21(1):v-v
Editorial announcement 相似文献