Synthesis and properties of azoles and their derivatives. 35. Synthesis of certain azoles containing sterically hindered phenol residues

The condensation of hydrochlorides of ethyl iminoesters of 4-hydroxy-3,5-di-tert-butylbenzoic and -(4-hydroxy-3,5-di-tert-butylphenyl) propionic acids with monoethanolamine, o-aminophenol, and o-phenylenediamine was studied. As a result, ²-oxazolines, benzoxazoles, and benzimidazoles containing sterically hindered phenol residues in the 2-position were synthesized.For Communication 34, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 889–892, July, 1984.     

Synthesis of porphyrins with reactive groups on phenyl rings. 8. Azo dyes on tetraphenylporphyrins

Porphynns having covalently attached residues of azo dyes on the periphery of the molecule have been synthesized by the diazotization of tetraaminophenylporphynns and subsequent azo coupling of the diazonium salts with phenol, and with - and -naphthols. The possibility of - electron interaction of the two chromophoric systems has been studied.Ivanovo State Institute of Chemical Technology, Ivanovo Center, 153460.Translated from Khimiya Geterotsklicheskikh Soedinenii, No. 8, pp. 1045–1049, August, 1996. Original article submitted July 2, 1996.     

Synthesis of 3-halobenzyl-4-hydroxycoumarins and their hydrolysis

The thermal condensation of halobenzylmalonic esters with phenol has given a series of 3-halobenzyl derivatives of 4-hydroxycoumarin. Alkaline hydrolysis, with simultaneous decarboxylation, gives the corresponding o-hydroxy--halophenylpropiophenones.     

Synthesis, Metal Complexation and Spectroscopic Characterization of Three New Azo Compounds

The synthesis of azo compounds [4-(N'-2-thiazol-2-ylsulfanyl)-4'-hydroxyazo benzene (1), 4-(N'-2-thiazol-2-ylsulfanyl)-2'-hydroxy-5-tert-butylazobenzene (2), 7-[4-(N'-2-thiazol-2-ylsulfanyl)phenylazo-8-hydroxy quinoline (3)] have been carried out by reacting phenol, 4-tert-butyl phenol and 8-hydroxy quinoline with N'-2-thiazol-2-ylsulfanylamide as coupling component. The resulting ligands (2 and 3) were treated with two transition metal salts (e.g., CuCl₂2H₂O andNiCl₂6H₂O). Cu(II) and Ni(II) complexes of the azo derivative ofphenol were obtained and characterised by IR, UV-Vis, ¹H NMR, spectroscopic and elemental analysis techniques. All the complexes have a metal : ligand ratio of 1 : 2 and are square-planar.     

Fulleropyrrolidine-containing sterically hindered phenol. Synthesis,structure, and properties

Fulleropyrrolidine containing a sterically hindered phenolic fragment was synthesized by the reaction of fullerene C₆₀ with N-methylglycine and 3,5-di-tert-butyl-4-hydroxybenzaldehyde. Electrochemical reduction of fulleropyrrolidine-containing phenol 1 and the corresponding phenoxide ion proceeded stepwise to form stable radical anions, dianions, and trianions. The radical anion (g = 2.0000) and the phenoxyl radical (g = 2.0045) obtained by chemical oxidation with lead dioxide were identified by ESR spectroscopy. The electron affinity of fulleropyrrolidine was estimated at 2.58 eV. For the phenoxide ion, the electrochemical gap was determined (E = E _I ^ox – E _I ^red = 0.47 V). The heats of formation and the energies of the frontier orbitals of fulleropyrrolidine and its transformation products were evaluated by the PM3 method.     

Synthesis and proton-acceptor capacities of 5-aryl-2-acetylthiophenes and 1-(5-aryl-2-thienyl)-1propenones

A number of 5-aryl-2-acetylthiophenes and 1-(5-aryl-2-thienyl)-3-phenyl-1-propenones were synthesized, and it was shown by means of their IR spectra that the 1-propenones are trans isomers with respect to the orientation of the substituents attached to the double bond and have an s-cis conformation. According to the data from the IR spectra of the H complexes of the investigated compounds with phenol, 5-aryl-2-acetylthiophenes have higher proton-acceptor capacities than acetophenones, 2-acetylthiophenes, and 4-acetyldiphenyl; a similar picture is also noted in a number of 1-propenones and 3-propenones. The transmission factors () obtained by Hammett correlation of the _Oh values for 1,4-phenylene, 2,5-thienylene, and vinylene groupings are identical and are equal to 0.8. It is shown on the basis of a correlation with respect to an equation of the Yukawa-Zuno type that the thiophene ring transmits polar conjugation better than the benzene ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1196–1202, September, 1976.     

Analogs of pyrimidine nucleosides. 15. Synthesis of 3′-hydroxy- and 4′-hydroxyftorafur

A method for the synthesis of ftorafur metabolites, viz., 3-hydroxy- and 4-hydroxyftorafur, from 3-benzoxytetrahydrofuran, which is chlorinated in the presence of UV irradiation, was developed. The resulting mixture of -chloro ethers is alkylated by 2,4-bis(trimethylsilyl)-5-fluorouracil. The alkylation products are separated by fractional crystallization and column chromatography on silica gel, and the benzoyl protective group is removed, cis-4-Hydroxyftorafut, trans-3-hydroxyftorafur, and cis-3-hydroxyftorafur, which were identified from the PMR spectra and by comparison with the literature data, were obtained.See [1] for Communication 14.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1094–1096, August, 1981.     

Synthesis of 2-hydrazino- and 2-amino-1,3,4-thiadiazines containing polyhydric phenol residues in the 5 position

2-Hydrazino-1,3,4-thiadiazines containing polyhydric phenol residues in the 5 position were obtained by reaction of 3,4-dihydroxy-, 2,5-dihydroxy-, and 2,3,4-trihydroxyphenacyl -halides with thiocarbohydrazide. 2-Amino-1,3,4-thiadiazines were obtained by reaction of 3,4-dihydroxy-and 2,5-dihydroxyphenacyl -halides with thiosemicarbazide in acidic and alcoholic media. In contrast to the dihydroxy derivatives, 2,3,4-trihydroxyphenacyl halide forms a 2-amino derivative only in strongly acidic media, whereas the isomeric thiazole compound with a hydrazine group in the 2 position of the thiazole ring is formed in alcoholic media.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1051–1055, August, 1976.     

Synthesis and properties of azoles and their derivatives. 10. Synthesis of 3,5-diaryl-4-nitroisoxazoles

A method was proposed for the synthesis of 3,5-diaryl-4-nitroisoxazoles entailing the brominatian of potassium salts of the corresponding 3,5-diaryl-²-isoxazolinyl-4-nitronic acids. The method may be used for the conversions of both the trans and cis isomers of 3,5-disubstituted 4-nitro-²-isoxazolines.Communication 9, See [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 189–192, February, 1985.     

Quinazolines X. Synthesis of 6,6'-methylenebisdeoxyvasicinone and its homologs

Summary 6,6-Methylenebisdeoxyvacisinone and its homologs have been synthesized by the reaction of methylenebisanthranilic acid with lactams (-butyrolactam, -valerolactam, -caprolactam, and -chloro- and ,-dichloro--caprolactams). The condensation of anthranilic acid and its derivatives (4-nitro-, 5-bromo-, 5-iodo-, and 5-nitroanthranilic acids) with ,-dichloro--caprolactam has given seven-membered analogs of deoxyvasicinone containing two chlorine atoms in the polymethylene ring.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 544–547, July–August, 1977.     

Synthesis of C5-substituted imidazolines

5-(Hydroxymethyl)-3-(t-butyloxycarbonyl)imidazoline 2 was prepared in four steps from 2,3-diaminopropionic acid in 72% overall yield. Mitsunobu reaction with a series of phenol derivatives gave the corresponding 5-(aryloxymethyl)-3-(t-butyloxycarbonyl)imidazolines 8a-l. Phthalimide and N-benzyl trifluoroacetamide also reacted.     

Interaction of acyl derivatives of the Fischer base with meta-substituted phenols. Synthesis of 2H- and 4H-spirochromenes of the indoline series

Acyl derivatives of the Fischer base react in the presence of phosphorus oxychloride with m-diethylaminophenol or resorcinol, forming spiro (indoline-2,2-[2H]chromenes) and spiro(indoline-2,4-[4H]chromenes). The ratio of the isomers depends on the solvent and the substituent in the phenol. The structure of the compounds obtained was established on the basis of the data of the ¹H and ¹³C NMR spectra.Translated from Khimiya Geterosiklicheskikh Soedinenii, No. 8, pp. 1101–1104, August, 1984.     

Furylcyclohexenones. 1. Synthesis and properties of 3- and 5-furyl-6-ethoxycarbonylcyclohexenones

3- and 5-Furylcyclohexenones were obtained by the Michael reaction of furan chalcones with acetoacetic ester. Intermediate -cycloketols were isolated in many cases. It was found that transformations of -cycloketols by HClO₄ and TrClO₄ were a function of the nature of the substituent in position5 of the alicycle. 5-Arylketols undergo dehydration, while 5-furyl derivatives split both water and the furan fragment, resulting in aromatization of the alicycle. The structure of the synthesized compounds was confirmed by the IR and PMR spectra.Kuban State Technological University, Krasnodar 350072. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 639–647, May, 1996. Original article submitted February 21, 1996.     

Halogen-containing Pyridines. 8. Synthesis of 3,5-Dichloropyridines Containing Pyrazole and Pyrazoline Residues in Position 2

The interaction of 3,5-dichloro-2-pyridylhydrazine with ,-unsaturated carbonyl compounds leads to 1-(3,5-dichloro-2-pyridyl)-3,5-disubstituted ²-pyrazolines. It was shown that N-(3,5-dichloro-2-pyridyl)hydrazones of the corresponding aldehydes and ketones are formed as intermediates. Condensation of the hydrazine mentioned above with ,-diketones gives 1,3,5-trisubstituted pyrazoles, but with acetoacetic ester a 1,3-disubstituted pyrazol-5-one containing a 3,5-dichloropyridyl residue is obtained.     

Pinched-cone Calix[6]arene: New Synthesis of p- (1,1,3,3-tetramethylbutyl)calix[6]arene. Structure of its 1 : 3 Complex with Chloroform

A new method is described for the synthesis of p-(1,1,3,3-tetramethylbutyl)calix[6]arene isolated ina 30 % yield. For the first time the crystal structure isgiven. The crystals are monoclinic, space group C2/c,a = 24.144(5) Å, b = 14.093(3) Å,c = 26.972(5) Å, = 93.36(3)^circ, V = 9162(3) ų, Z = 4. The macrocycle with C2symmetry presents the pinched-cone conformation. It crystallizes with three chloroform molecules, two of them are positioned in the cones shaped by the phenol moieties; the third chloroform is located in the cavity near the hydroxyl groups; this solvent molecule is disordered around the 2 axis. The packing of the complex is described.     

Transformed steroids. 133. Synthesis of 20-deoxysteroids with a tetrahydropyran ring E

The synthesis of 20-deoxy compounds — the precursors of the steroid pyranols and pyranones synthesized by the authors previously — has been effected from a steroid 20-ketotetrahydropyran by the hydrogenolysis of the corresponding ethylene dithioketal with Raney nickel. The¹H and¹³C NMR spectra have been studied in detail. Transformations of rings A and B via the epoxide or the 3,5-cyclosteroid have led to 3-acetoxy-16,23-epoxy-5H-21,24-dinorchol-5-en-6-one and 3-acetoxy-5-hydroxy-16,23-epoxy-21,24-dinorchol-5-en-6-one.N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 732–735, November–December, 1983.     

m-Aminophenylarsonic Acid as a Reagent for the Extraction Preconcentration of Phenol

The azocoupling reaction of phenol with the diazonium salt of m-aminophenylarsonic acid was used for the determination of phenol in water at a level of maximum permissible concentrations. The resulting compound is stable in a wide pH range, which made it possible to develop a procedure for the determination of phenol with the preconcentration of the azo compound by extraction to isobutanol at pH 2 and subsequent back extraction to the aqueous phase at pH 10. The high concentration coefficient of phenol (65) provides for determination of phenol down to 0.9 g/L.     

Linear free energy relationships for peroxy radical-phenol reactions. Influence of the para-substituent,the ortho-di-tert-butyl groups and the peroxy radical

Calculations were carried out on several data sets to study the mechanism of hydrogen abstraction from phenols by peroxy radicals: (1) Rate constants, k values, were collected for the reactions of cumyl-, 1-phenylethyl- and tert-butyl-peroxy radicals with ortho-para-substituted phenol inhibitors. The rate constants were recalculated for the same temperature. Solvent effects were neglected because the solvents used were similar in nature. The phenol ortho substituents were characterized by an indicator variable I_tBu accounting for the presence or absence of di-tert-butyl groups. The phenol para substituents were characterized by Charton's σ_I, σ_R, and σ substituent constants. The dependence of log k values on I_tbu, σ_I, σ_R, σ was investigated using stepwise linear regression analysis. The combined data set of 32 reactions gives: and The results suggest that hydrogen abstraction from phenols by peroxy radicals proceeds by an electrophilic mechanism, and that neither the peroxy-radical nor the ortho-di-tert-butyl groups have considerable effect on the rate of reaction (1).     

Alkylation of aromatics. Kinetics of phenol alkylation with methanol

A kinetic study of phenol alkylation with methanol in the presence of -Al₂O₃ has been carried out. A mechanism involving the reaction of phenol and methanol adsorbed on acid-base pair sites is proposed.     

Indole derivatives CI. Synthesis and biological activity of some tryptamines

The cyclization of hydrazones obtained by coupling of diazonium salts with ethyl-acetyl--phthalimidovalerate gives ethyl 5-substituted-3-(2-phthalimidoethyl)indole-2-carboxylates, the successive hydrolysis and decarboxylation of which make it possible to obtain 5-substituted tryptamines. The synthesized hydroxyethyl ester of serotonin was found to have pronounced antiradiation action.See [1] for communication C.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1496–1501, November, 1974.