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It was found that oligo(hexamethylene guanidine) (OHMG) reacted very slowly with unactivated high-molecular-mass alkyl halides (dodecyl chloride), possibly due to steric hindrance and the low nucleophilicity of the guanidine moiety. Therefore, this alkyl halide could not be used to modify OHMG under conventional conditions. Ethylation of OHMG was much more facile. However, the substitution in the derivatives was broadly scattered (under ordinary conditions and reagent ratios). It was shown simultaneously that the antibacterial activity of the alkylated derivatives was less than that of the starting OHMG hydrochloride. Benzyl chloride reacted readily with OHMG to produce derivatives with the desired degree of substitution. It was found that benzyl derivatives with 0.2 degree of substitution were more active against mycobacteria than the starting hydrochloride with the activity gradually diminishing if the degree of substitution was increased further. The increased activity may have been related to the optimum increase of OHMG hydrophobicity and/or steric structure. The rather high antibacterial activities of the benzyl derivatives against Mycobacterium smegmatis strain ATCC 607 made them promising for further development and studies of the properties of alkylated OHMG derivatives to discover more active derivatives, including against M. smegmatis. The most obvious candidates could become the methylcarboxy-substituted OHMG derivatives.

A procedure has been proposed for the synthesis of pyridines from 1,2,4-triazine derivatives and bicyclo[2.2.1]hepta-2,5-diene under high pressure in the presence of lithium perchlorate as catalyst.

Acylation of indole and 2,5-dimethylthiophene with 2-(3-indolyl)-2-oxoacetyl chloride afforded the corresponding diketones. 1-(2,5-Dimethyl-3-thienyl)-2-(3-indolyl)ethanedione reacted with thiosemicarbazide under atmosperic and elevated pressure to give 6-(2,5-dimethyl-3-thienyl)-5-(3-indolyl)-2,3-dihydro-1,2,4-triazine-3-thione whose structure was studied in detail by the X-ray diffraction method. Reactions of 6-(2,5-dimethyl-3-thienyl)-5-(3-indolyl)-2,3-dihydro-1,2,4-triazine-3-thione with amines and hydrazine resulted in formation of fused triazolo- and tetrazolotriazines.

N,N-Disubstituted 2-aminooxazoles in acetic acid at 20°C undergo addition of maleinimide, converting to alkylidene succinimides or 1,2-oxazine derivatives.

N,N-Disubstituted 2-aminooxazoles react with maleimide in two directions: heterodiene synthesis with the formation of imides of 2-aminopyridine-3,4-dicarboxylic acids and/or 1,3-cycloaddition, forming imides of 2-amino-5-acyl-Δ1-pyrrolidine-3,4-dicarboxylic acids.

Substituted dihydropyrroles were characterized by13C and1H NMR spectra. The spectral patterns of these compounds and reversible hydrogen—deuterium exchange are discussed.

Reactions of haloarenes with urotropine in CF3COOH at elevated temperatures and high pressures give the corresponding aromatic aldehydes and/orN-(haloarylmethyl)trifluoroacetamides. The yeilds of the products and their ratio depend on electronic properties of substituents in the aromatic ring. The reaction carried out in a mixture of CF3COOH and (CF3CO)2O affords only amides.

N,N-Disubstituted 2-aminooxazoles react with maleimide in two directions: heterodiene synthesis with the formation of imides of 2-aminopyridine-3,4-dicarboxylic acids and/or 1,3-cycloaddition, forming imides of 2-amino-5-acyl-Δ1-pyrrolidine-3,4-dicarboxylic acids.

The hitherto inaccessible nitroolefin (VII), which is the most convenient intermediate for the synthesis of the psychotropic amine (VIII), has been obtained by the direct condensation at high pressures (up to 1500 MPa) of piperonal (V) with 1-nitropropane (VI). The structure of (VII) was confirmed by direct synthesis from pyrocatechol (X). The amine (VIII) was obtained in three steps from (VII). This synthesis of (VIII) is shorter than that previously reported.

A procedure was proposed for regioselective acylation of methyl 2-methyl-4H-thieno[3,2-b]-pyrrole-5-carboxylate with 2-(3-indolyl)-2-oxoacetyl chloride. Reactions of the resulting methyl 6-[2-(3-indolyl)-1,2-dioxoethyl]-2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylate with aromatic aldehydes and ammonium acetate in acetic acid afforded the corresponding methyl 6-[2-aryl-4-(3-indolyl)imidazol-5-yl]-2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylates. The structure of methyl 6-[2-(4-chlorophenyl)-4-(3-indolyl)imidazol-5-yl]-2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylate was studied by X-ray analysis.

N,N-Disubstituted 2-aminooxazoles in acetic acid at 20°C undergo addition of maleinimide, converting to alkylidene succinimides or 1,2-oxazine derivatives.