Results 161 to 170 of about 121,691 (212)

Iodocyclization of 1,4-dihydropyridines

Tetrahedron Letters, 1998
Abstract Iodine (or related species) addition to 1,4-dihydropyridines, with properly attached substituents at the nitrogen atom, leads to the corresponding 3-iodotetrahydropyridinium ions, which undergo an internal nucleophilic attack to furnish regio- and stereoselectively iodobi(poly)lteterocyclic ring systems in good yields.
Rodolfo Lavilla, Oscar Coll, Marta Nicolàs, Joan Bosch   +3 more
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The oxidation of 1,4-dihydropyridines

Chemistry of Heterocyclic Compounds, 1970
The olefinic bond of methenylbisindan-1,3-dione, 2-benzylideneindan-1, 3-dione, and its derivatives is easily reduced by many 1, 4-dihydropyridines. Under the conditions described, other functional groups are untouched. These Β-dicarbonyl compounds are utilized to compare the effects of substituents in 1,4-dihydropyridines on their reactivity in the ...
G. Ya. Dubur, Ya. R. Uldrikis
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The photochemistry of 3,5-disubstituted 1,4-dihydropyridines

Tetrahedron, 1970
Abstract On irradiation, 1,4-dihydropyridines have been shown to undergo three types of reaction: disproportionation, isomerization and dimerization. The presence of 2,6-substituents inhibits these reactions except in the case of 3a which undergoes disproportionation.
U, Eisner, J R, Williams, B W, Matthews, H, Ziffer   +3 more
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Synthesis of Bis‐1,4‐dihydropyridine Derivatives.

ChemInform, 2005
Abstract A series of bis‐1,4‐dihydropyridine derivatives were synthesized by the reaction of p‐phenylenedialdehyde or m‐phenylenedialdehyde and active methylene compounds.
Songlei Zhu, Shujang Tu, Yuan Gao, Chunbao Miao, Tuanjie Li, Xiaojing Zhang, Fang Fang, Daqing Shi   +7 more
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Aromatization of 1,4‐Dihydropyridines with Selenium Dioxide.

ChemInform, 2005
AbstractFor Abstract see ChemInform Abstract in Full Text.
Xiao-hua Cai, Hai-jun Yang, Guo-lin Zhang   +2 more
openaire   +1 more source

Photoprotection of 1,4-dihydropyridine derivatives by dyes

International Journal of Pharmaceutics, 2005
The possibility of increasing the photochemical stability of nisoldipine by using indigotine and azorubine as photoprotectors has been studied. The course of the photodegradation was monitored by means of UV-vis spectrophotometry and HPLC. Quantitative assessments of the nisoldipine photodegradation included evaluation of the quantum yields and kinetic
Jadwiga, Mielcarek, Włodzimierz, Augustyniak, Paweł, Grobelny, Grazyna, Nowacka   +3 more
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The 1,4-Dihydropyridine Receptor

Journal of Cardiovascular Pharmacology, 1984
Evidence that nitrendipine (2,6-dimethyl-3-carbomethoxy-5-carbomethoxy-4-(3-nitrophenyl)1,4- dihydropyridine) and other 1,4-dihydropyridines interact at a specific site to antagonize Ca2+ channel function is reviewed. This evidence derives from electrophysiologic and pharmacologic studies and is confirmed by [3H]radioligand binding to excitable tissues.
D J, Triggle, R A, Janis
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1,4-Dihydropyridines bearing a pharmacophoric fragment of lidoflazine

Bioorganic & Medicinal Chemistry, 1996
A series of 1,4-dihydropyridines bearing a pharmacophoric fragment of lidoflazine was synthesized. The compounds were evaluated for inotropic, chronotropic, and calcium antagonist activities. All compounds behave as inotropic and chronotropic agents, except for compounds 4b, 5a, and 5b, which exhibit a rather weak calcium antagonism in vascular smooth ...
Chiarini A., Rampa A., Budriesi R., Bisi A., Fabbri G., Valenti P.   +5 more
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A new synthesis of 1,4-dihydropyridines

Journal of the Chemical Society, Perkin Transactions 1, 1975
The synthesis of 1,4-dihydropyridines unsubstituted in the 1-, 2-, and 6-positions from methyl propiolate, aromatic aldehydes, and ammonium acetate in acetic acid is described. The products were oxidised to the corresponding pyridines. Certain features of their n.m.r. spectra are discussed.
Tomy Chennat, Ulli Eisner
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Construction of 1,4-Dihydropyridines: The Evolution of C4 Source

Topics in Current Chemistry, 2023
The field of cascade cyclization for the construction of 1,4-dihydropyridines (1,4-DHPs) has been continuously expanding during the last decades because of their broad-spectrum biological and synthetic importance. To date, many methods have been developed, mainly including the Hantzsch reaction, Hantzsch-like reaction and newly developed cascade ...
Siyu, Song, Yongchao, Wang, Fuchao, Yu
openaire   +2 more sources