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11.
Ahmed F. A. Shalaby Mohamed M. Abdulla Abd El Galil E. Amr Azza A. Hussain 《Monatshefte für Chemie / Chemical Monthly》2007,138(10):1019-1027
Summary. A series of substituted heterocyclic systems were prepared from N1-[4-(4-fluorocinnamoyl)phenyl]-5-chloro-2-methoxybenzamide, which was prepared from the corresponding 5-chloroanisic acid
(2-methoxy-4-chlorobenzoic acid) as starting material. Treating of the cinnamoyl derivative with hydrazine hydrate in dioxane
afforded a pyrazoline, which was reacted with morpholine and paraformaldehyde to give the N-substituted pyrazoline. Acylation of pyrazoline with acetyl chloride in dioxane afforded the N-acetyl analogue. Also, the cinamoyl derivative was reacted with methylhydrazine, phenylhydrazine, or ethyl cyanoacetate to
yield the corresponding N-methyl-, N-phenylpyrazoline, pyrane, and pyridone derivatives. Condensation of the cinnamoyl derivative with cyanothioacetamide gave
the pyridinethione derivative, which was treated with ethyl chloroacetate affording the ethyl carboxylate derivative. Also,
it was reacted with malononitrile or ethyl acetoacetae to give the cyano amino analougues and ethyl carboxylate, which was
reacted with methylhydrazine to give the (indazolyl)phenyl derivative. On the other hand, reaction of cinnamoyl derivative
with acetyl acetone afforded the cyclohexenyl derivative, which was reacted with hydrazine hydrate to give the [methylindazolyl]phenyl
derivative. Condensation of the cinnamoyl derivative with guanidine hydrochloride or thiourea afforded the aminopyrimidine
derivative and thioxopyrimidine. The latter was condensed with chloroacetic acid to yield a thiazolopyrimidine, which was
condensed with 2-thiophenealdehyde to yield the arylmethylene derivative, however, it was also prepared directly from thiopyrimidine
by the action of chloroacetic acid, 2-thiophenealdehyde, and anhydrous sodium acetate. The pharmacological screening showed
that many of these compounds have good anti-arrhythmic activity and low toxicity. 相似文献
12.
A new sono-electrochemical method for enhanced detoxification of hydrophilic chloroorganic pollutants in water 总被引:8,自引:0,他引:8
Yasman Y Bulatov V Gridin VV Agur S Galil N Armon R Schechter I 《Ultrasonics sonochemistry》2004,11(6):649-372
A new method for detoxification of hydrophilic chloroorganic pollutants in effluent water was developed, using a combination of ultrasound waves, electrochemistry and Fenton's reagent. The advantages of the method are exemplified using two target compounds: the common herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) and its derivative 2,4-dichlorophenol (2,4-DCP). The high degradation power of this process is due to the large production of oxidizing hydroxyl radicals and high mass transfer due to sonication. Application of this sono-electrochemical Fenton process (SEF) treatment (at 20 kHz) with quite a small current density, accomplished almost 50% oxidation of 2,4-D solution (300 ppm, 1.2 mM) in just 60 s. Similar treatments ran for 600 s resulted in practically full degradation of the herbicide; sizable oxidation of 2,4-DCP also occurs. The main intermediate compounds produced in the SEF process were identified. Their kinetic profile was measured and a chemical reaction scheme was suggested. The efficiency of the SEF process is tentatively much higher than the reference degradation methods and the time required for full degradation is considerably shorter. The SEF process maintains high performance up to concentrations which are higher than reference methods. The optimum concentration of Fe2+ ions required for this process was found to be of about 2 mM, which is lower than that in reference techniques. These findings indicate that SEF process may be an effective method for detoxification of environmental water. 相似文献
13.
Moustafa A. Gouda Moged A. Berghot Ghada E. Abd El‐Ghani Abd El‐Galil M. Khalil 《Journal of heterocyclic chemistry》2016,53(4):1241-1250
One‐pot condensation of malononitrile 1 , furan‐2‐carbaldehyde 2 , butan‐2‐one 3 , and ammonium acetate in ethanol, followed by cyanoacetylation of the formed nicotinonitrile 4 with 3‐(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)‐3‐oxopropanenitrile 5 afforded the cyanoacetamide 6 . Compound 6 was used as a key intermediate for synthesis of nicotinonitriles via reaction with different reagents. 相似文献
14.
Moustafa A. Gouda Ghada E. Abd El‐Ggani Moged A. Berghot Abd El‐Galil M. Khalil 《Journal of heterocyclic chemistry》2019,56(7):2036-2045
As a part of ongoing studies in developing new potent antioxidant agents, 2‐amino‐4‐(furan‐2‐yl)‐5,6‐dimethylnicotinonitrile 4 was utilized as a key intermediate for the synthesis of some new pyrimidines 5 and 11 , form (acet)amide 6 , 7 , urea and thiourea 9 , 10 , 1,8‐naphthyridines 12 , 13 , and 14 . Moreover, condensation of 4 with 5,5‐dimethyl‐1,3‐cyclohexanedione and cyclohexanone in ethanol furnished the pyridine derivatives 16 and 17 , respectively. Furthermore, refluxing of 4 with ethylenediamine in carbon disulfide afforded the 4,5‐dihydro‐1H‐imidazol‐2‐yl pyridine derivative 19 . In addition, refluxing of 4 with carbon disulfide and concentrated sulfuric acid furnished the pyridine derivatives 20 and 21 , respectively. The reaction of 4 with phenacyl chloride and ethyl chloroacetate in dimethylformamide in the presence of catalytic amount of triethylamine afforded the pyridine derivatives 22 and 23 , respectively. Finally, heating of 4 with 1‐phenyl‐3‐(piperidin‐1‐yl)propan‐1‐one hydrochloride in glacial acetic acid afforded phenylpropylamino pyridine derivative 24 . The structures of the newly synthesized compounds were confirmed by elemental analysis, IR, 1H‐NMR, and mass spectral data. Representative compounds of the synthesized products were evaluated as antioxidant agents. Compounds 8 , 19 , and 22 are promising compounds. 相似文献
15.
OK Yoon WG Hwang JC Choe MS Kim 《Rapid communications in mass spectrometry : RCM》1999,13(14):1515-1521
A technique to investigate photodissociation kinetics on a nanosecond time scale has been devised for molecular ions generated by multiphoton ionization (MPI) using mass-analyzed ion kinetic energy spectrometry. The branching ratio or rate constant has been determined for the photodissociation of the n-butylbenzene, bromobenzene, iodobenzene, and aniline molecular ions generated by MPI at 266 nm. The ion internal energies have been estimated by comparing the measured kinetic data with the previous energy dependence data. The analysis has shown that only those molecular ions generated by two-photon ionization contribute to the photodissociation signals. Around half of the available energy has been found to remain as molecular ion internal energy in the two-photon ionization process. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
16.
Doria S. Badawy Noha M. Awad Ebrahim Abdel‐Galil 《Journal of heterocyclic chemistry》2013,50(6):1351-1356
New approaches for the synthesis of some heterocyclic compounds, such as the pyridopyrimidodiazepine derivative 3 , pyrazolopyrido[1,2‐a]pyrimidine derivative 4 , tetrazolo[1.5‐a][1,8]naphthyridine derivative 9 , pyrazolylpyrido[1,2‐a]pyrimidine derivatives 10a , 10b , 12 , pyrrolopyrido[1,2‐a]pyrimidine derivatives 14a , 14b , 14c , 14d , and 16a , 16b , starting from 2‐chloro‐4H‐4‐oxo‐pyrido[1,2‐a]pyrimidine ( 1 ), are described. 相似文献
17.
First, the basic concept of the vector derivative in geometric algebra is introduced. Second, beginning with the Fourier transform
on a scalar function we generalize to a real Fourier transform on Clifford multivector-valued functions
Third, we show a set of important properties of the Clifford Fourier transform on Cl3,0 such as differentiation properties, and the Plancherel theorem. Finally, we apply the Clifford Fourier transform properties
for proving an uncertainty principle for Cl3,0 multivector functions. 相似文献
18.
19.
20.
For an integers letl
s
(n), thes-iterated logarithm function, be defined inductively:l
0
(n)=n,l
s+1
(n)=log2 (l
2
(n)) fors0. We show that for every fixeds and alln large enough, there is ann-vertex 3-pushdown graph whose smallest separator contains at least(n/l
s
(n)) vertices.The work of the first author was supported in part by NSF Grants MCS-83-03139, DCR-85-11713 and CCR-86-05353.The work of the second author was supported in part by NSF Grants MCS-84-16190. 相似文献