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1.
The corresponding 2-phenyl-3-(2-furyl)- and 2-phenyl-3-[-(2-furyl)vinyl]-1,2-dihydronaphtho-[1,2-d]-1,2,4-triazines were obtained by heating Schiff bases [prepared by reaction of 1-(phenyl-azo)-2-aminonaphthalene with furfural, -(2-furyl)acrolein, and their 5-bromo and 5-nitro derivatives] in glacial acetic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 158–160, February, 1973.  相似文献   

2.
A reaction of 3-allyl- and 3-phenylthiohydantoins with 1,5-diphenyl- and 1-phenyl-substituted 3-formyl-2-pyrazolines was used to obtain a series of 5-(pyrazolin-3-ylmethylidene)-2-thioxotetrahydro-4H-imidazol-4-ones, the subsequent alkylation of which with methyl iodide or ethyl chloroacetate gave the corresponding 2-alkylthio-5-(pyrazolin-3-ylmethylidene)-3,5-dihydro-4H-imidazol-4-ones in the yields from 30 to 77%. The oxidation of (5Z)-3-phenyl-5-[(1,5-diphenylpyrazolin-3-yl)methylidene]-2-methylsulfanyl-4,5-dihydroimidazol-4-one with lead tetraacetate led to the corresponding pyrazole in 48% yield.  相似文献   

3.
Summary. Ab initio calculations at the HF/6-31G* level of theory for geometry optimization and MP2/6-31G*//HF/6-31G* for a single point total energy calculation are reported for the important energy-minimum conformations and transition-state geometries of (Z,Z)-, (E,Z)-, and (E,E)-cyclonona-1,5-dienes. The C2 symmetric chair conformation of (Z,Z)-cyclonona-1,5-diene is calculated to be the most stable form; the calculated energy barrier for ring inversion of the chair conformation via the Cs symmetric boat-chair geometry is 58.3kJmol–1. Interconversion between chair and twist-boat-chair (C1) conformations takes place via the twist (C1) as intermediate. The unsymmetrical twist conformation of (E,Z)-cyclonona-1,5-diene is the most stable form. Ring inversion of this conformation takes place via the unsymmetrical chair and boat-chair geometries. The calculated strain energy for this process is 63.5kJmol–1. The interconversion between twist and the boat-chair conformations can take place by swiveling of the trans double bond with respect to the cis double bond and requires 115.6kJmol–1. The most stable conformation of (E,E)-cyclonona-1,5-diene is the C2 symmetric twist-boat conformation of the crossed family, which is 5.3kJmol–1 more stable than the Cs symmetric chair–chair geometry of the parallel family. Interconversion of the crossed and parallel families can take place by swiveling of one of the double bonds and requires 142.0kJmol–1.  相似文献   

4.
Ab initio calculations at the HF/6-31G* level of theory for geometry optimization and MP2/6-31G*//HF/6-31G* for a single point total energy calculation are reported for the important energy-minimum conformations and transition-state geometries of (Z,Z)-, (E,Z)-, and (E,E)-cyclonona-1,5-dienes. The C2 symmetric chair conformation of (Z,Z)-cyclonona-1,5-diene is calculated to be the most stable form; the calculated energy barrier for ring inversion of the chair conformation via the Cs symmetric boat-chair geometry is 58.3kJmol–1. Interconversion between chair and twist-boat-chair (C1) conformations takes place via the twist (C1) as intermediate. The unsymmetrical twist conformation of (E,Z)-cyclonona-1,5-diene is the most stable form. Ring inversion of this conformation takes place via the unsymmetrical chair and boat-chair geometries. The calculated strain energy for this process is 63.5kJmol–1. The interconversion between twist and the boat-chair conformations can take place by swiveling of the trans double bond with respect to the cis double bond and requires 115.6kJmol–1. The most stable conformation of (E,E)-cyclonona-1,5-diene is the C2 symmetric twist-boat conformation of the crossed family, which is 5.3kJmol–1 more stable than the Cs symmetric chair–chair geometry of the parallel family. Interconversion of the crossed and parallel families can take place by swiveling of one of the double bonds and requires 142.0kJmol–1.  相似文献   

5.
Summary The title compounds (5) were prepared by addition of 2-phenyl-1,3-dithiane anion (2-lithiated10) to adequately substituted N-alkyl-3,4-dihydroisoquinolinium salts (7a–7g). Cleavage of compounds5 with HgO/BF3 affords S-benzoyl-1,3-propanedithiol (4a) and the corresponding disulfide4c, benzaldehyde, and Hg(I) ions. In contrast to the title compounds, 2-(-dialkylaminobenzyl)-2-phenyl-1,3-dithianes (6) yield benzil under these conditions.In commemoration of the late Prof. Dr. Dr. h.c. mult.Horst Böhme, Marburg/Germany, an outstanding representative of Pharmaceutical Chemistry  相似文献   

6.
Uroš Urši? 《Tetrahedron》2010,66(24):4346-1445
(2E,3Z)-2-(1-Methyl-2,5-dioxoimidazolidin-4-ylidene)-3-[(arylamino- or heteroarylamino)methylene]succinate 5 obtained by [2+2] cycloaddition of (5Z)-5-[(dimethylamino)methylene]-3-methylimidazolidine-2,4-dione (1) and dimethyl acetylenedicarboxylate (2) followed by substitution of the dimethylamino group with aromatic or heteroaromatic amines, afforded by heating in ethanol in the presence of potassium hydroxide, potassium salts 6. Acidification of 6 with hydrochloric acid afforded mixtures of (E)- and (Z)-isomers of methyl 4-(2-hydroxy-1-methyl-5-oxo-1H-imidazol-4(5H)-ylidene)-5-oxo-1-phenyl-4,5-dihydro-1H-pyrrole-3-carboxylates. On the other hand, alkylation of compounds 6 with methyl iodide or benzyl bromide produced the corresponding methyl (E)-4-(2-methoxy- or 2-benzyloxy-1-methyl-5-oxo-1H-imidazol-4(5H)-ylidene)-5-oxo-1-phenyl-4,5-dihydro-1H-pyrrole-3-carboxylates 9, derivatives of a new triazafulvalene system.  相似文献   

7.
The UV spectra of 2-phenyl-4-azaindan-1, 3-dione (I), 2-phenyl-5-azaindan-1, 3-dione (II), and their N-methylbetaines are investigated. 2×10–5 M aqueous alcoholic solutions of 2-phenyl-4-azaindan-1, 3-dione (I) contain the anionic form (IA), and in solutions of 2-phenyl-5-azaindan-1, 3-dione (II) the betaine form (IIB) is also in equilibrium with the anion (IIA). Solutions of I and II in 0.1 M sulfuric acid are characterized by a wide and rather intense absorption band at about 500 m, indicating the presence of a betaine form (IB and IIB). In 2M hydrochloric acid solution 2-phenylazaindan-1, 3-diones and their N-methylbetaines (III and IV) are protonated at the oxygen atom, giving the enol forms of the N-protonated or corresponding N-methylated 2-phenylazaindandiones.  相似文献   

8.

Abstract  

An efficient synthesis method for the preparation of a series of new (Z)- and (E)-3(5)-(2-hydroxyphenyl)-4-styrylpyrazoles was developed. The reaction of (Z)- and (E)-3-styrylchromones with hydrazine hydrate afforded the corresponding (Z)- and (E)-3(5)-(2-hydroxyphenyl)-4-styrylpyrazoles, except for nitro derivatives, where both (Z)- and (E)-4′-nitro-3-styrylchromones afforded (E)-3(5)-(2-hydroxyphenyl)-4-(4-nitrostyryl)pyrazoles. The reaction mechanism for these transformations is discussed and the stereochemistries of all products were established by NMR experiments.  相似文献   

9.
Proton–ligand dissociation constants of 4-sulfamethazineazo-3-methyl-1-phenyl-2- pyrazolin-5-one (SMP) and metal–ligand stability constants of its complexes with bivalent metal ions (Mn2+, Co2+, Ni2+ , Cu2+, and Zn2+) have been determined potentiometrically in 0.1 M KCl, and a 40% (v/v) ethanol–water mixture. The order of the stability constants of the complexes was found to be Mn2+ < Co < Ni < Cu < Zn. The dissociation constants, pK H, of SMP and the stability constants, log K, of its complexes were determined at different temperatures and the corresponding thermodynamic parameters ( G, H, and S) were derived and discussed. The dissociation process is nonspontaneous, endothermic, and entropically unfavorable. The formation of the complexes were found to be spontaneous, endothermic, and entropically favorable.  相似文献   

10.
A reaction of the sodium salt of 3-phenyl-5(Z)-(pyridin-2-ylmethylidene)-2-selenoxoimidazolidin-4-one (NaL) with CoCl2·6 H2O in MeCN gave rise to the complex CoL2 in 56% yield. Cyclic voltammetry showed that the coordination compound formed was reversibly reduced “at the metal”. According to the CVA data, the product of its reduction, in contrast to the earlier synthesized sulfur-containing analog, undergoes alkylation with n-butyl iodide at the organic ligand fragment.  相似文献   

11.
The reaction of 1-phenyl-3-(3,4-dimethoxyphenyl)-3-(2-oxocyclohexyl)-1-propanone with hydrogen sulfide and acids gives an intramolecular rearrangement product, 2-phenyl-2,4-ortho-(14,15-dimethoxybenzo)-cis-1-thiadecalin in addition to the usual products of disproportionation of intermediate 2-phenyl-4-(3,4-dimethoxyphenyl)-5,6-tetramethylene-4H-thiopyran, namely, 5,6-tetramethylenethiopyrilium salts and 2-phenyl-4-(3,4-dimethoxyphenyl)-cis-1-thiadecalin. The configurational and conformational assignments for the sulfides, their sulfoxides, and sulfones were made by 13C NMR spectroscopy.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 199–205, February, 1986.  相似文献   

12.
The condensation of (2E)-N-hydroxy-2-hydroxyimino-2-phenylethanamine with 3,4,5-trimethoxyphenylglyoxal afforded (1-hydroxy-5-phenyl-1H-imidazol-2-yl)phenylmethanone which reacted with trimethyl phosphite or chloroacetone to give 2-(3,4,5-trimethoxybenzoyl)-4(5)-phenyl-1H-imidazole.  相似文献   

13.
Reaction of phenyl acetylene with 3-(1-aryl-2-mercapto-4-imidazolyl)-2H-1-benzopyran-2-ones (4) in the presence of sodium hydroxide in absolute ethanol led to the formation of 3-(1-phenyl-2-(Z-styrylthio)-1H-imidazol-4-yl)-2H-chromen-2-ones (6) in excellent yields. These, on further oxidation with H2O2/AcOH, gave the corresponding sulfones (7) with retention of stereochemistry.

Additional information

ACKNOWLEDGMENT

We are grateful for financial support from the Council of Scientific and Industrial Research (CSIR), New Delhi, Project No. 01 (2062) 06/EMR-II.  相似文献   

14.
Summary N-Cyano-S-methyl-isothio-ureases (1) react with -halogen ketones (2) by ring closure yielding the (3H-oxazol-2-yliden)-cyanamides3. by ring transformation, 2-Alkoxy-5-amino-1-phenyl-3H-imidazol-4-yl)-ketones (4) are formed. Primary and secondary amines react with3 to give 2-N-alkylated (2,5-Diamino-1-phenyl-3H-imidazol-4-yl)-ketones.
  相似文献   

15.
Two crystal modifications (m-1 and m-2) of the mixed-ligand complex ZnPhen(i-PrOCS2)2 have been isolated. Their crystal structures were solved using X-ray diffraction data (CAD-4 diffractometer, MoK radiation, 3141 and 3532 Fhkl, R = 0.0363 and 0.0304). For both modifications, the crystals are monoclinic with unit cell parameters a = 10.543(2), b = 13.494(3), c = 16.875(3) , = 102.08(3)°, V = 2347.6(8) 3, Z = 4, space group P21/n (m-1) and a = 10.931(2), b = 12.996(3), c = 16.288(3) , = 92.69(3)°, V = 2311.3(8) 3, Z = 4, space group P21/n (m-2). The structures basically consist of discrete monomer molecules in which the Zn atom has a tetragonal pyramidal (m-1: ZnN2S3, c.n. 5, bidentate and monodentate i-PrOCS 2 - ligands) or distorted octahedral (m-2: ZnN2S4, c.n. 6, bidentate i-PrOCS 2 - ligands) environment. Molecular packings and their interactions in the structures are discussed.  相似文献   

16.
The configurational and conformational features of the trans and cis isomers of 3-methyl-2-phenyl-5-(3-methyl-2-phenyl-3,4-dehydropiperid-6-yl)pyridine, formed as by-products in the phenylation of -picoline by phenyllithium, were established. The revealed stereospecificity of the 5JHH and 1JCH SSCCs may be utilized as an independent criterion in the conformational analysis of piperideine systems.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 71–74, January, 1993.  相似文献   

17.
2-(2-Aminophenyl)-4-hydroxy-3-phenyl-1-isoquinolone was unexpectedly obtained in the reaction of 3-(-bromobenzyl)-3-bromophthalide with o-phenylenediamine. The isoquinolone in chloroform undergoes autooxidation by air oxygen to give 2-(2-aminophenyl)-3-hydroperoxy-3-phenyl-1,4-dioxo-1,2,3,4-tetrahydroisoquinoline, which is subsequently converted to N-(2-benzamidophenyl)phthalimide. A mechanism is proposed for the rearrangement of the hydroperoxide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 83–87, January, 1982.  相似文献   

18.
5-Amino-3-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-7-phenyl-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile was synthesized via the reaction of 4-(2-aminothiazol-4-yl)-3-methyl-1-phenyl-2-pyrazolin-5-one with benzylidene malononitrile and was then transformed to related fused heterocyclic systems. The antifungal and antibacterial studies revealed in some cases excellent biocidal properties.  相似文献   

19.
The bromination of 2-styrylchromones, bearing electron neutral substituents, with two molar equivalents of piridinium tribromide gave 2-(2-aryl-1,2-dibromoethyl)chromones and 3-bromo-2-(2-aryl-1,2-dibromoethyl)chromones. The presence of electron-donating substituents on their B ring led to a mixture of compounds due to the higher reactivity of their C(2)=C(3) and C=C double bonds, whereas the strongly electron-withdrawing group hindered the bromination. The dehydrobromination of 2-(2-aryl-1,2-dibromoethyl)chromones with triethylamine gave a diastereomeric mixture of (E)- and (Z)-2-(-bromostyryl)chromones. Some novel 4(5)-aryl-5(4)-(2-chromonyl)-1,2,3-triazoles have been obtained from the reactions of 2-(2-aryl-1,2-dibromoethyl)chromones, 2-(-bromostyryl)chromones, and 2-styrylchromones with sodium azide. The reactions of 2-styrylchromones with sodium azide are more efficient, general, and constitute a one-pot synthetic method of 4(5)-aryl-5(4)-(2-chromonyl)-1,2,3-triazoles allowing the preparation of 1,2,3-triazoles bearing either electron-donating or electron-withdrawing substituents in their aryl ring. The structure of all new compounds was established by extensive NMR spectroscopic studies.  相似文献   

20.
2-Polyfluoroalkylchromones reacted with diethylenetriamine at 20 °C to form the corresponding 1,4,8-triazabicyclo[5.3.0]dec-4-ene derivatives. The crystal structures of 5-(2-hydroxyphenyl)-7-trifluoromethyl-1,4,8-triazabicyclo[5.3.0]dec-4-ene and 1-(2-aminoethyl)-7-(2-hydroxy-5-methoxyphenyl)-5-(1,1,2,2-tetrafluoroethyl)-2,3-dihydro-1H-1,4-diazepine were established by X-ray diffraction analysis.  相似文献   

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