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1-Substituted benzimidazoles are readily annelated regio- and stereoselectively with α,β-acetylenic γ-hydroxyacidnitriles under mild conditions (20–25 °C, no catalyst, no solvent) to form new polyfunctional condensed systems, 4-cyanomethylene-1,3-oxazolobenzimidazoles (30–88 % yield). Unexpectedly, the latter, when chromatographed on neutral Al2O3 at room temperature, undergo a complex multi-position hydrolytic rearrangement involving the cleavage of the imidazole ring to aminophenyl N-substituted formamides with an aminodihydrofuran moiety in the aminophenylsubstituent, N-(2-{[5-amino-2,2-dialkyl-3(2H)-furanylidene]amino}phenyl)-N-substituted formamides, a novel class of highly functionalized pharmacophoric compounds. The results contribute to the basic benzimidazole chemistry and provide for prospective families of drug candidates.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Metal complexes (I) show high indices of metastasis inhibition of B16 melanoma and Lewis lung carcinoma experimental tumors.

Ethanolysis of cycloadducts (I) results in formation of bicycloheptadienones (III) and dihydrofuranones as minor products in case of (IVa-d).

The O-(arylcarbamoyl)butyrhydroximoyl chlorides were synthesized, and the x-ray structural analysis (XSA) of one of them — O-(o-tolylcarbamoyl)butyrhydroximoyl chloride — was performed. It was established from the data of the XSA and the PMR spectra that all synthesized compounds are the Z isomers.

1-X-1-Oxo-1,2-dihydro-4H-3,1-benzoxaphosphorins (X = CH2Cl, Ph, and OH) were obtained by reacting ortho-(butoxymethoxymethyl)phenylmagnesium bromide with derivatives of chloromethylphosphonic and chloromethylphosphinic acids, followed by intramolecular alkylation. X-Ray diffraction was used to study the molecular and crystalline structure of one of these compounds (with X = OH).

Synthesis of titled representatives of alkenylsulfenylchlorides by the reaction of SCl2 with allenes 1 and 2 is described and their AdE reactions with some model olefins are discussed.

6,7-Dialkynyl-1,3-dimethylpteridine-2,4(1H,3H)-diones and 2,3-dialkynylquinoxalines have been shown to react with sodium azide in DMF at room temperature giving rise 9,11-dimethyl-[1,2,3]triazolo[1′,5′;1,2]pyrido[4,3-g]pteridine-8,10(9H,11H)-diones and [1,2,3]triazolo[1′,5′;1,2]pyrido[3,4-b]quinoxalines. A novel tandem cyclization involves 1,3-dipolar cycloaddition of an azide ion to the carbon–carbon triple bond followed by intramolecular nucleophilic addition of the intermediate 1,2,3-triazole N-anion to another C C bond.

The one-pot reaction of natural amino acids (glycine, β-alanine, γ-aminobutyric and ɛ-aminocapronic acids, d , l -valine, d , l -leucine, anthranilic acid) with bielectrophilic acylacetylenes proceeds chemo-, regio- and stereospecifically in the presence of NaOH (45–50 °C, 4 h, EtOH–H2O) to give (after treatment of the reaction mixture with aqueous HCl) Z-isomers of N-acylvinyl derivatives of amino acids in 87–94% yield.

2-Aminobenzoic acid 1 reacts with α,β-acetylenic γ-hydroxy nitriles 4 and 5 to afford 2-[(5-iminio-2,2-dialkyl-2,5-dihydro-3-furanyl)amino]benzenecarboxylates 7 and 8 (yield 73–74%), a new class of unnatural amino acids in a peculiar zwitterionic form, having the positive charge transferred to the remote imino group of the dihydrofuranyl substituent. 3- and 4-Aminobenzoic acids 2 and 3 with α,β-acetylenic γ-hydroxy nitriles 4–6 undergo entirely different transformations to deliver the esters of cyanomethylhydroxyalkyl ketones 9–12, which result from the unusually facile esterification of the hydroxyl function and simultaneous hydration of the triple bond. 4-Aminobenzoic acid 3 is found to be an active organic catalyst for the one-pot conversion of α,β-acetylenic γ-hydroxy nitrile 4 to 5-amino-2,2-dimethyl-3(2H)-furanone 13, in 80% yield.

A new procedure was developed for the synthesis of 6-phenyltetrazolo[1,5-b]triazin-7-one. Aza analogs of uracil and isocytosine were prepared by the tetrazole ring cleavage. It was demonstrated that these transformations can be used in the synthesis of anomalous nucleosides.

Tri-and tetracyclic compounds were synthesized by the cyclization of 6-alkoxy-2,3-dicyano-5-nitromethyl-1,4,5,6-tetrahydropyrazines with 1,2,3-triazinium and quinoxalinium cations.

A simple procedure for the synthesis of N,N,N′-trialkyl-1,8-diaminonaphthalenes is described. It consists in partial demethylation (dealkylation) of commercially available proton sponge [1,8-bis(dimethylamino)naphthalene] and some of its derivatives at heating with HBr–KI–DMF system. Limitation, scope and a possible mechanistic pathway for the reaction are discussed. For isomeric 8-dimethylamino-1-methylamino- and 1-dimethylamino-8-methylamino-4-nitronaphthalenes, X-ray measurements have been conducted. The first examples of complete realkylation reactions in the naphthalene proton sponges are reported.

1-Difluoronitroacetyl-4-arylpiperazines were synthesized. The molecular structure of 1-difluoronitroacetyl-4-(p-fluorophenyl)piperazine was established by x-ray diffraction structural analysis.