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91.
Watanuki S Matsuura K Tomura Y Okada M Okazaki T Ohta M Tsukamoto S 《Chemical & pharmaceutical bulletin》2011,59(8):1029-1037
A series of 1-isopropyl-1,2,3,4-tetrahydroisoquinoline derivatives were synthesized and their bradycardic activities were evaluated in isolated guinea pig right atria. Structure-activity relationship studies revealed that the introduction of an appropriate substituent and its position on the 1,2,3,4-tetrahydroisoquinoline ring are essential for potent in vitro activity. Furthermore, the tether between the piperidyl moiety and the terminal aromatic ring is important for potent antihypertensive activity. Oral administration of 6-fluoro-1-isopropyl-2-{[1-(2-phenylethyl)piperidin-4-yl]carbonyl}-1,2,3,4-tetrahydroisoquinoline (3b) to spontaneously hypertensive rats (SHR) elicited antihypertensive effects without inducing reflex tachycardia, which is often caused by traditional L-type Ca2? channel blockers. 相似文献
92.
Watanuki S Matsuura K Tomura Y Okada M Okazaki T Ohta M Tsukamoto S 《Chemical & pharmaceutical bulletin》2011,59(11):1376-1385
We synthesized and evaluated inhibitory activity against T-type Ca(2+) channels for a series of 1-alkyl-N-[(1R)-1-(4-fluorophenyl)-2-methylpropyl]piperidine-4-carboxamide derivatives. Structure-activity relationship studies have revealed that the isopropyl substituent at the benzylic position plays an important role in exerting potent inhibitory activity, and the absolute configuration of the benzylic position was found to be opposite that of mibefradil, which was first launched as a new class of T-type Ca(2+) channel blocker. Oral administration of N-[(1R)-1-(4-fluorophenyl)-2-methylpropyl]-1-[2-(3-methoxyphenyl)ethyl]piperidine-4-carboxamide (17f) lowered blood pressure in spontaneously hypertensive rats without inducing reflex tachycardia, an adverse effect often caused by traditional L-type Ca(2+) channel blockers. 相似文献
93.
94.
Iwayama Y Ando H Tanaka HN Ishida H Kiso M 《Chemical communications (Cambridge, England)》2011,47(34):9726-9728
The glycan moiety of ganglioside HPG-7, isolated from the sea cucumber (Holothuria pervicax), was synthesized for the first time. The characteristic substructure, a trisialic acid sequence embedded in the glycan, was deliberately constructed by utilizing suitably differentiated sialyl units for various synthetic purposes. Finally, a pentasaccharide was successfully delivered as the hexyl glycoside. 相似文献
95.
Kazunori Masuko Chiharu Kumano Ryo Sugawara Kazuhiro Nakabayashi Hideharu Mori 《Journal of polymer science. Part A, Polymer chemistry》2021,59(15):1664-1677
A series of amino-acid-based amphiphilic diblock copolymer nano-objects having different morphologies were developed by reversible addition–fragmentation chain-transfer (RAFT) dispersion polymerization of styrene (St) in methanol. This was mediated by six different hydrophilic poly(N-acryloyl amino acid) macro-chain transfer agents (CTAs), including three carboxylic-acid-containing ones, poly(N-acryloyl-l -proline) (PAProOH), poly(N-acryloyl-4-trans-hydroxy-l -proline) (PAHypOH), and poly(N-acryloyl-l -threonine) (PAThrOH) prepared by RAFT polymerization, and their methyl ester forms, PAProOMe, PAHypOMe, and PAThrOMe. The effects of polymerization conditions on RAFT dispersion polymerization of St using a dithiocarbamate-terminated PAProOH was investigated. A systematic study of the effects of monomer conversion and concentration afforded the formation of various morphologies (i.e., spheres, worms, and vesicles). The effects of hydrogen-bonding and ionic interactions of the macro-CTAs on the assembled structures of the nano-objects were evaluated using six different macro-CTAs. Transforming the products from methanol to water via dialysis produced amino-acid-based block copolymer nano-objects, exhibiting pH-responsive morphological change, in aqueous solution. 相似文献
96.
Mitsuru Izumi Toshiki Nakayama Kunimitsu Uchinokura Ryozo Yoshizaki Etsuyuki Matsuura 《Molecular Crystals and Liquid Crystals》2013,570(1-4):79-82
Metallic phase of NbS3 was synthesized by heating the crystal of semiconducting NbS3. Metallic NbS3 undergoes superconducting transition around 2 K. The analysis of the angular dependence of the upper critical magnetic field suggests that the effect of filmy or fibrous morphology plays an important role in the superconducting properties. 相似文献
97.
Kentaro Kimura Hideharu Sato Atsushi Kameyama Tadatomi Nishikubo 《Journal of polymer science. Part A, Polymer chemistry》2000,38(18):3399-3404
The polycondensation of bis(4‐mercaptophenyl) sulfide (BMPS) with bis(4‐chloro‐3‐nitrophenyl) sulfone (BCNPS) was examined using various organic or inorganic bases in mixed solvents of N‐methyl‐2‐pyrrolidone (NMP) with water or in plain water. The reaction of BMPS with BCNPS proceeded smoothly to give the corresponding polysulfide in mixed solvents of NMP with water at 60 °C using 1,8‐diazabicyclo[5.4.0]undecene‐7 as a base, although the rate of the reaction decreased gradually as the water in the solvent increased. Polysulfide can also be obtained by reaction in plain water using appropriate organic bases such as tripropylamine (TPA) or quinoline. The polysulfide with a number‐average molecular weight of 45,100 was synthesized in 62% yield when the reaction of BMPS with BCNPS was performed using TPA as a base at 60 °C for 48 h in plain water. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3399–3404, 2000 相似文献
98.
Low-loss and rugged distal tips for CO2 laser have been proposed and fabricated based on a commercially available stainless steel (St) pipe. A method of smoothening the inner surface of the St pipe with a rough inner surface is put forward. Fabrication parameters, transmission properties, and mechanical strength of the cyclic olefin polymer-coated silver hollow St distal tip are experimentally discussed. 相似文献
99.
Kazuhiko Hashimoto Sirinat Wibullucksanakul Mitsuyasu Matsuura Masahiko Okada 《Journal of polymer science. Part A, Polymer chemistry》1993,31(12):3141-3149
Ring-opening polyaddition of a saccharic acid dilactone prepared from D-glucose, D-glucaro-1,4 : 6,3-dilactone, with several alkylenediamines proceeded at room temperature with no catalyst. The resulting new polyamides carrying many pendant hydroxyl groups, poly(alkylene D-glucaramide)s, were more amorphous and hydrophilic than the corresponding nylons having no hydroxyl groups, and were hydrolyzed more easily than the latter in an acidic condition. The ring-opening ability of D-mannaro-1,4:6,3-dilactone, which was another saccharic acid dilactone obtained from D-mannitol, was found to be lower than that of the D-glucaric analogue. © 1993 John Wiley & Sons, Inc. 相似文献
100.