The formation of 1,2,4-triazolylimidazolidine-2,4-diones in reactions of 3-aryl-1,2,4-triazin-5(2H)-ones with alkylureas

Recyclization of the addition products of alkylureas to 3-aryl-1,2,4-triazin-5(2H)-ones affording 1,2,4-triazole derivatives was found to occur in Ac₂O.     

Direct diastereoselective introduction of l-menthol residue into 1,2,4-triazin-5(4H)-one

The reaction of 3-phenyl-1,2,4-triazin-5(4H)-one (1) with l-menthol in the presence of aliphatic acid anhydrides results in (6S)- and (6R)-1-acyl-6-(l-menth-3-yl)-1,6-dyhydro-3-phenyl-1,2,4-triazin-5(4H)-ones. The reaction is diastereoselective with predominant formation of (6S)-isomers. The reaction diastereoselectivity increases with enhancement of the steric hindrance in the vicinity of the reaction center of the azine.     

Synthesis of mono meso-pyridyl 21,23-dithiaporphyrins and unsymmetrical non-covalent porphyrin dimers

A new method has been developed to synthesize 21,23-dithiaporphyrins having one pyridyl group at the meso position. The method required easily available unknown precursors and the condensation resulted in mono meso-pyridyl 21,23-dithiaporphyrins as single products in 8-11% yield. Two of the three mono meso-pyridyl N₂S₂ porphyrins were used to synthesize non-covalent unsymmetrical porphyrin dimers containing one N₂S₂ and one N₄ porphyrin cores.     

1,2,4-Triazine in Organic Synthesis. 16. Reactivity of 3-Substituted 6-Phenyl-1,2,4-triazines towards Phenylacetonitrile Anion in Polar Aprotic Solvents

The reactions of 3-X-6-phenyl-1,2,4-triazines (X = SMe, SPh, SO2Ph) with phenylacetonitrile anion in DMF were studied. In these reactions the ring transformation product 3-amino-4,6-diphenylpyridazine, the covalent addition product 3-X-5-(-cyanobenzyl)-6-phenyl-2,5-dihydro-1,2,4-triazine, and the ipso-substitution product 3-(1-cyano-1-phenylmethyl)-6-phenyl-1,2,4-triazine were obtained. Analogous reactions carried out in DMA gave only the addition products in excellent yields as diastereomeric mixtures of the corresponding 2,5-dihydro-1,2,4-triazines.     

Synthesis of meso-furyl porphyrins with N4, N3S, N2S2 and N3O porphyrin cores

A series of meso-furyl porphyrins with four different porphyrin cores (N₄, N₃S, N₂S₂ and N₃O) were synthesized and characterized. The comparison of NMR, optical and fluorescence properties of meso-furyl porphyrins with porphyrins with six-membered aryl groups indicates that electronic properties of porphyrins were changed drastically on the introduction of furyl groups at meso positions. The maximum shifts in spectral bands were observed for meso-furyl porphyrins with N₂S₂ core. On protonation, the absorption bands of meso-furyl porphyrins were further red shifted. All these changes were ascribed to the possibility of more planarity of the meso-furyl porphyrins due to the small size of the furyl groups which results in extending the π-delocalisation of the porphyrin ring in to the furyl groups.     

Azolo[5,1-<Emphasis Type="Italic">c</Emphasis>]-1,2,4-triazines as a new class of antiviral compounds

Synthetic methods, reactivity, and the properties of a new class of antiviral compounds, pyrazolo-, imidazo-, 1,2,4-triazolo[5,1-c]-1,2,4-triazinones, tetrazolo[5,1-b]-1,2,4-triazinones, and azoloannulated amino-1,2,4-triazines having structural similarity with biogenic purines and capable of mimicking them in metabolic processes are considered. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 967–995, May, 2008.     

Femtosecond dynamics of relaxation of photoexcited meso-tetraferrocenylporphyrin in the nonprotonated and diprotonated forms (Fc4PH2 and Fc4PH42+)

The relaxation of the Q¹(—*) excited state of the nonprotonated Fc₄PH₂ and diprotonated Fc₄PH₄ ²⁺ forms of meso-tetraferrocenylporphyrin was studied by femtosecond laser absorption spectroscopy. Transition from the Q¹(—*) state to the charge-transfer state was shown to occur within 208±10 fs for Fc₄PH₂ and 9±3 ps for Fc₄PH₄ ²⁺. A fast vibrational relaxation with a characteristic time of 120—140 fs was found for both forms. The relaxation time of Fc⁺—P^– charge-transfer state for Fc₄PH₂ was 17±4 ps.     

meso-四(对烷氧基苯基)卟啉锌配合物的合成、表征及热力学性质

合成得到系列meso-四(对烷氧基苯基)卟啉及其锌配合物的晶体，其结构经 ¹H NMR，UV-Vis和元素分析确证。研究了配合物与吲哚客体的轴向配位热力学性质。结果表明:主体与客体的配位数均为1;不同主体的平衡常数与电子效应和空间效应有关。研究了温度对平衡常数的影响，发现平衡常数随温度升高而降低。根据平衡常数计算了配合过程的热力学参数Δ_rH_m^?，Δ_rS_m^?和Δ_rG_m^?，结果表明反应为放热、熵减过程。     

Synthesis of heterocyclic systems with a carbohydrate fragment

Levoglucosenone, the ,ß-unsaturated ketone obtained by the pyrolysis of cellulose, reacts with NH-azoles in the presence of bases. In this process not only normal Michael adducts are formed, but in some cases their hydrates (gem-diols) are also formed. In all cases the addition proceeds stereospecifically and with good yields. 3-Nitro-s-triazole, 3-nitro- and 4-nitropyrazoles, 3-methyl-4-nitropyrazole, 5-nitrotetrazole, 4,5-dicarbomethoxy-v-triazole, 3,4-dinitropyrazole, 3(5)-methylpyrazole, pyrazole, and imidazole have been studied in this reaction. All of the adducts are characterized by NMR- and IR-spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1135–1140, June, 1994.     

中位-四(对烷氧苯基 )卟啉 Co2+、Cu2+、Zn2+、Pb2+配合物的合成与表征

Synthesis of fourteen new complexes of meso-tetrakis(4-alkoxyphenyl) porphyrins with Co²⁺, Cu²⁺, Zn²⁺, Pb²⁺ were presented in this paper.Meso-tetrakis (4-alkoxyphenyl) porphyrins were prepared by condensation of 4-alkoxybenzaldehydes with pyrrole, then treated with corresponding metallic acetate to produce mentioned complexes, IR, UV, ¹H NMR, MS and elementary analysis were explored to confirm the structures of all theses new complexes.Characteristic spectrometric data of IR, UV, ¹H NMR related to these complexes have been systematically summarized.Ten of the fourteen complexes were found to exhibit liquid crystal properties.     

Synthesis of N-trinitroethyl derivatives of linear and heterocyclic nitrogen-containing compounds

Earlier unknown N-trinitroethyl derivatives of acetylhydrazine, 4-amino-1,2,4-triazole, and 2,4,6-triamino-1,3,5-triazine, which are potential components for gas-generating formulations, were synthesized. Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1306–1309, May, 2005.     

Porphyrins. 37. Synthesis of heterodimers of porphyrins and chlorins containing pyrrolyl-methyl bridges

We have obtained various adducts, including homodimers and heterodimers of ethanebisporphyrins and ethanebischlorins containing pyrrole and dipyrrylmethane insertions, by reaction of mesodimethylaminomethylporphyrins and chlorins with -unsubstituted pyrrole derivatives in the presence of methyl iodide.For Communication 36, see [1].Dedicated to Professor M. A. Yurovskaya on her Jubilee.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 336–341, March, 2000.     

Nucleophilic substitution of hydrogen in the reaction of 1,2,4-triazin-4-oxides with cyanamide

It was shown that cyanamide can successfully be used in reactions of nucleophilic substitution of hydrogen with 1,2,4-triazin-4-oxides in the presence of a base to give 5-cyanoimino-1,2,4-triazines. It was found by¹³C NMR spectroscopy that these compounds and their alkylation products at the cyclic nitrogen atom exist in the form of 5-cyanoimino-2,5-dihydro-1,2,4-triazines. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1128–1130, June, 2000.     

Porphotetramethenes with 1,3-alternate conformation of pyrrole rings from oxidative N-alkylation of porphyrin tetraphenols

Tetrapyrrole macrocycles, of which the pyrroles are connected by sp2 centers, were readily obtained from porphyrin tetraphenols by air oxidation under basic conditions, followed by N-alkylation. The degree of N-alkylation could be controlled and either di- or tetraalkylated derivatives are obtained in high yields.     

<Emphasis Type="Italic">meso</Emphasis>-Aryltetrabenzoporphyrins. Synthesis and properties

The most considerable achievements in the synthesis and investigations of meso-aryltetrabenzoporphyrins and their metal complexes are reviewed. The choice of the route to, and the properties of, these compounds depends on the nature and number of meso-aryl substituents. The reviewed synthetic methods are compared. Selected physicochemical and spectroscopic properties of meso-aryltetrabenzoporphyrins are analyzed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1565–1580, August, 2008.     

Study of complex formation between lead(II) acetate andmeso-tetraphenylporphin

The reaction of Pb(OAc)₂ withmeso-tetraphenylporphin in boiling pyridine orN,N-dimethylformamide gave complexes of Pb^II with tetraphenylchlorin or Pb^IV with tetraphenylporphin. The scheme of redox reactions occurring during the complex formation involving Pb²⁺ as the reducing agent was suggested. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2052–2055, October, 1998.     

Functionalization of benzo[b][1,6]naphthyridine derivatives

Two routes to consecutive functionalization of 3-chloro-4-cyanobenzo[b][1,6]naphthyridine (1a) at positions 3 and 10 were developed. Oxidation of compound 1a with m-chloroperbenzoic acid in acetone leads to 3-chloro-4-cyano-10-oxobenzo[b][1,6]naphthyridine, while in acetic acid, the reaction gives 3-chloro-4-cyano-10-(3-chlorobenzoyloxy)-5-hydroxy-5,10-dihydrobenzo[b][1,6]naphthyridine. The reactions of 1a with some C-nucleophiles give -adducts at position 10. The reactions of N,N-dimethylamide acetals with chloride 1a leads to 4-cyano-3-dimethylaminobenzo[b][1,6]naphthyridine.