Synthesis of 3,5-dicyano-4-phenyl-2,6-bis(4-p-terphenylyl)-1,4-dihydropyridine. An attempt at extending the Hantzsch synthesis

1985 ◽  
Vol 50 (9) ◽  
pp. 1962-1970 ◽  
Author(s):  
Štefan Marchalín ◽  
Josef Kuthan

The 3-oxopropanenitrile IIIc, prepared from 4-acetyl-p-terphenyl (IV) by the sequence IV → V → VI → IIIc, reacts with benzaldehyde and ammonium acetate in acetic acid to give the Hantzsch 1,4-dihydropyridine VIIc and the corresponding pyridine derivative VIIIc. The alternative cyclocondensation of benzylidene derivative IIc and 3-oxopropanenitrile IIIc in the presence of ammonium acetate exclusively gives the pyridine derivative VIIIc. Rate of thermal and oxidative aromatizations of the 1,4-dihydropyridine derivatives, VIIa → VIIc → VIIIa → VIIIc, decreases in the order VIIc > VIIb > VIIa. Mechanism of these transformations and spectral characteristics of compounds VIIc and VIIIc are discussed with regard to their molecular structure.

2020 ◽  
Vol 34 (2) ◽  
pp. 385-405
Author(s):  
R. M. Mohareb ◽  
M. M. Kamel ◽  
Y. R. Milad

The reaction of the 3-oxo-N,3-diphenylpropan-amide (3) with either malononitrile or ethyl cyanoacetate in ammonium acetate gave the 1,2-dihydropyridine derivatives 6a or 6b, respectively. On the other hand, carrying the same reaction in the presence of triethylamine gave the 1,6-dihydropyridine derivatives 7a and 7b, respectively. Moreover, compound 3 reacted with 2-aminoprop-1-ene-1,1,3-tricarbonitrile to give the pyridine derivative 9. Compound 7b reacted with the active methylene derivatives 10a,b and 4a,b to give the naphthyridine derivatives 11a,b and 12a,b; respectively. Compound 3 was also used for the synthesis of thiophene derivatives 13a,b and 16a,b. In addition, the reaction of ethyl benzoylacetate (1) with o-phenylene diamine gave the benzimidazole derivative 18. The reactivity of the latter product towards different reagents was studied to give different products. The cytotoxicity of the newly synthesized products was studied towards some cancer and normal cell lines, in addition toxicity of compounds was measured and docking of the most active compounds was done. Compounds 6b, 7b, 9, 13a, 13b, 16a, 20b, 20c, 24b, 25 and 26b exhibited optimal cytotoxic effect against cancer tested cell lines. These active compounds were evaluated against c-Met kinase using foretinib as the reference drug where all compounds expressed higher activity than the reference drug.                     KEY WORDS: Ethyl benzoylacetate, Pyridine, Benzimidazole, Cytotoxicity   Bull. Chem. Soc. Ethiop. 2020, 34(2), 385-405 DOI: https://dx.doi.org/10.4314/bcse.v34i2.15


2019 ◽  
Vol 16 (8) ◽  
pp. 676-682
Author(s):  
Ankusab Noorahmadsab Nadaf ◽  
Kalegowda Shivashankar

The polycyclic dihydropyridine nucleus represents the heterocyclic system of invaluable core motifs with wide applications in chemical, biological and physical properties. Although this kind of compounds have been extensively synthesized by other groups, the synthesis of these compounds under CFL light intensity were not explored. The synthesis of polycyclic dihydropyridine derivatives were achieved through the reaction of 4-hydroxycoumarin, aromatic aldehydes and ammonium acetate under CFL light irradiation conditions. A series of polycyclic dihydropyridine derivatives were prepared under CFL light irradiation conditions with high yield, short reaction time, ambient condition and without the use of catalyst. The results displayed an efficient method for the synthesis of polycyclic dihydropyridine derivatives. Clean profile, short reaction time, low cost and use of CFL light intensity instead of catalyst making it a genuinely green protocol.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Viktoriia Savchenko ◽  
Iulia Emilia Brumboiu ◽  
Victor Kimberg ◽  
Michael Odelius ◽  
Pavel Krasnov ◽  
...  

AbstractQuenching of vibrational excitations in resonant inelastic X-ray scattering (RIXS) spectra of liquid acetic acid is observed. At the oxygen core resonance associated with localized excitations at the O–H bond, the spectra lack the typical progression of vibrational excitations observed in RIXS spectra of comparable systems. We interpret this phenomenon as due to strong rehybridization of the unoccupied molecular orbitals as a result of hydrogen bonding, which however cannot be observed in x-ray absorption but only by means of RIXS. This allows us to address the molecular structure of the liquid, and to determine a lower limit for the average molecular chain length.


1983 ◽  
Vol 24 (3) ◽  
pp. 400-407
Author(s):  
A. E. Obodovskaya ◽  
L. M. Shkol'nikova ◽  
L. O. Atovmyan ◽  
I. A. Seliverstova ◽  
V. G. Yashunskii ◽  
...  

1980 ◽  
Vol 33 (6) ◽  
pp. 1323 ◽  
Author(s):  
JB Bremner ◽  
EJ Browne ◽  
PE Davies ◽  
CLWAH Raston

The heterocyclic derivatives, 8,9-dimethoxy-3-methyl-1-phenyl-3,4,5,6- tetrahydro-1H-2,3-benzoxazocine(3a) and 9,10-dimethoxy-3-methyl-1- phenyl-1,3,4,5,6,7-hexahydro-2,3-benzoxazonine (3b),examples of two new ring systems, have been prepared by Meisenheimer rearrangement of the corresponding 2-benzazepine and 2-benzazocine N-oxide derivatives (2a) and (2b). The Bischler-Napieralski-type cyclization reaction was used in the preparation of the tertiary amine precursors of these N-oxides reaction conditions for the cyclization were critical and phosphorus oxychloride in refluxing butanenitrile was found to give the best yields of the seven- or eight-membered cyclic imine intermediates. Reductive cleavage of the benzoxazocine derivative (3a) with zinc in acetic acid followed by N-methylation gave the expected product, [2-{3- (dimethylamino)propyl}-4,5-di-methoxyphenyl]phenylmethanol (12). The crystal and molecular structure of (3a) has been determined by X-ray crystallographic analysis.


1995 ◽  
Vol 6 (6) ◽  
pp. 525-531
Author(s):  
Michal W. Wieczorek ◽  
Wieslaw Majzner ◽  
Magdalena Sikora ◽  
J�zef Kula

2020 ◽  
Author(s):  
Viktoriia Savchenko ◽  
Iulia-Emilia Brumboiu ◽  
Victor Kimberg ◽  
Michael Odelius ◽  
Pavel Krasnov ◽  
...  

Abstract Quenching of vibrational excitations in resonant inelastic X-ray scattering (RIXS) spectra of liquid acetic acid is observed. At the oxygen core resonance associated with localized excitations at the O-H bond, the spectra lack the typical progressionof vibrational excitations observed in RIXS spectra of comparable systems. We interpret this phenomenon as due to strong rehybridization of the unoccupied molecular orbitals as a result of hydrogen bonding. This allows us to address the molecular structure of the liquid, and to determine a lower limit for the average molecular chain length.


2020 ◽  
Vol 168 (4) ◽  
pp. 453-456
Author(s):  
N. V. Kudryashov ◽  
E. A. Ivanova ◽  
T. S. Kalinina ◽  
A. A. Shimshirt ◽  
A. A. Kurshin ◽  
...  

2019 ◽  
Vol 1195 ◽  
pp. 815-826 ◽  
Author(s):  
Seema S. Khemalapure ◽  
Vinay S. Katti ◽  
Chidanandayya S. Hiremath ◽  
Mahantesha Basanagouda ◽  
Sudhir M. Hiremath ◽  
...  

1974 ◽  
Vol 29 (7-8) ◽  
pp. 552-555 ◽  
Author(s):  
Purshottam S. Kendurkar ◽  
Ram S. Tewari

Reactions of N-pyridinium phenancylides with different a, β-unsaturated ketones give 2,4,6-triarylsubstituted pyridines, 2,6-diphenyl-4-(2-pyridyl) pyridines, 2-benzylidene-4,6-diphenyl pyridines and 2,4,6-triphenyl-3-bromopyridine. Ammonium acetate in acetic acid was used as cyclization agent. The structure of the products are supported by IR and NMR spectra.


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