Results 191 to 200 of about 235,743 (243)

1,4-Dihydropyridines containing sulfur (review)

Chemistry of Heterocyclic Compounds, 1995
The literature on the synthesis and reactions of monocyclic and polycyclic 1, 4-dihydropyridines containing sulfur in substituents or in the ring is reviewed.
Ya. Ozols, B. Vigante, G. Duburs
openaire   +1 more source

Enhanced mechanofluorochromic properties of 1,4-dihydropyridine-based fluorescent molecules caused by the introduction of halogen atoms

CrysteEngComm, 2019
Halogen-substituted 1,4-dihydropyridine derivatives exhibit higher contrast mechanofluorochromic properties than the derivative without a halogen atom because of more twisted conformations and looser stacking arrangements.
Yating Chen, Yibin Zhou, Zhiqiang Wang, Mengzhu Wang, Wenxia Gao, Yunbing Zhou, Miao-chang Liu, Xiaobo Huang, Hua-yue Wu   +8 more
semanticscholar   +1 more source

Vicinal diamination of 1,4-dihydropyridines

Chemical Communications, 1998
Electrophilic interaction of iodine with N-alkyl-1,4-dihydropyridines 1 in the presence of secondary amines stereoselectively leads to the corresponding trans-2,3-diamino-1,2,3,4-tetrahydropyridines 2 in satisfactory yields (79–94%); the method allows the synthesis of piperidine, pyrrolidine, morpholine and piperazine derivatives.
Rodolfo Lavilla, Rakesh Kumar, Oscar Coll, Carme Masdeu, Joan Bosch   +4 more
openaire   +1 more source

Reactions of 1,4-dihydropyridines (review)

Chemistry of Heterocyclic Compounds, 1993
The literature published over the period 1986–1990 on the chemical properties (oxidation, addition, substitution, reactions of the functional groups, etc.) of 1,4-dihydropyridines is correlated.
A. Sausin'sh, G. Dubur
openaire   +1 more source

V 2 O 5 /ZrO 2 as an efficient reusable catalyst for the facile, green, one-pot synthesis of novel functionalized 1,4-dihydropyridine derivatives

Catalysis Today, 2017
A practical method is designated for the one-pot, multicomponent synthesis of 1,4-dihydropyridine derivatives by cyclo-condensation of aromatic aldehydes, 5,5-dimethyl-1,3-cyclohexanedione, acetoacetanilide and ammonium acetate.
S. V. Bhaskaruni, S. Maddila, W. E. Zyl, S. Jonnalagadda   +3 more
semanticscholar   +1 more source

One-Pot Assembly for Synthesis of 1,4-Dihydropyridine Scaffold and Their Biological Applications

Polycyclic aromatic compounds (Print), 2019
A one-pot procedure for the preparation of functionalized 1,4-dihydropyridines by three-component reaction using substituted heterocyclic aldehydes, ammonium acetate, and substituted β-ketoesters catalyzed by L-proline was described.
Mayank G. Sharma, J. Pandya, D. M. Patel, Ruturajsinh M. Vala, V. Ramkumar, R. Subramanian, V. Gupta, Ramesh L Gardas, Anuradha Dhanasekaran, H. Patel   +9 more
semanticscholar   +1 more source

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
openaire   +1 more source

MIL-101-SO3H metal–organic framework as a Brønsted acid catalyst in Hantzsch reaction: an efficient and sustainable methodology for one-pot synthesis of 1,4-dihydropyridine

New Journal of Chemistry, 2019
A straightforward and efficient methodology for the synthesis of the medicinally important 1,4-dihydropyridines has been demonstrated using MIL-101-SO3H metal–organic framework as a sustainable Brønsted acid catalyst.
Nainamalai Devarajan, P. Suresh
semanticscholar   +1 more source

Metalation of 1,4-dihydropyridine esters

Tetrahedron Letters, 1989
Abstract 4-Aryl-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarboxylic esters are metalated at the NH and the C-2 methyl positions via tretament with two equivalents of n-butyl lithium. The resulting dilithio species can be treated with a variety of electrophiles to furnish C-2 methyl functionalized dihydropyridine esters.
Graham S. Poindexter, Michael A. Foley, Joseph F. Licause   +2 more
openaire   +1 more source

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
openaire   +2 more sources