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This paper addresses the modification of epoxy-amine systems with new reactive compounds, oligohexamethyleneguanidine salts. Using commercial hydrochloride of oligohexamethyleneguanidine, its hydrosalicylate, hydro-5-sulfosalicylate, and hydro-4-aminosalicylate are isolated and characterized. During salt preparation, the main macromolecular chain of oligohexamethyleneguanidine remains almost intact. The scheme advanced for the covalent introduction of a modifier in an epoxy-amine network involves the preliminary synthesis of the adduct of an epoxy oligomer and oligohexamethyleneguanidine salt followed by its cure with oligoamine. Conditions for formation of uncured viscous-flow adducts well miscible with the epoxy oligomer and the curing agent are determined. Using these adducts, the cured elastic films are obtained, among which samples modified with oligohexamethylene-guanidine hydro-4-aminosalicylate demonstrate the most pronounced activity against model microorganisms Mycobacterium smegmatis. These materials show promise as a basis for the development of biocidal coatings.

Using commercial oligohexamethyleneguanidine hydrochloride, oligohexamethyleneguanidine hydrosalicylate having a higher solubility in epoxy resins is synthesized. On its basis, covalent adducts with epoxy resins are obtained in the medium of dimethyl sulfoxide. The kinetics of synthesis of these adducts and the stoichiometric ratio of oligohexamethyleneguanidine and an epoxy oligomer are studied by refractometry. Adducts are cured using oligomeric amine with allowance for the real content of epoxy groups. As a result, free elastic films having the glass transition temperature below room temperature are obtained. The activity of the modified films against gram-positive and gram-negative microorganisms is revealed. This indicates that the studied composites show promise for creating bactericidal coverings.

Condensed pregnano[17,16-d]triazolines were produced in 1,3-dipolar cycloaddition of 16-dehydropregnenolone acetate with organic azides at 10 kbar. The structure of the synthesized compounds was determined by using two-dimensional NMR spectroscopy (1H—1H COSY, NOESY, HSQC, and HMBC).

Approaches to creating complexes based on branched oligohexamethyleneguanidine hydrochloride are addressed. Novel combinations of bactericidal agents were obtained, methods for the synthesis of a series of p-aminosalicylic acid derivatives were selected, the solubilities of their complexes with oligohexamethyleneguanidine were determined, and the bactericidal activities of the resulting complexes against Mycobacterium smegmatis were assessed. The minimum inhibitory concentrations of all complexes were in the range 0.1 – 1 μg/ml of culture medium. Thus, these complexes may be useful for creating a bactericidal formulation with powerful and long-lasting biocidal action, highly reproducible properties, and low toxicity.

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.

Oligo(hexamethyleneguanidine) (OHMG) hydrochloride samples with various molecular weights that were synthesized from hexamethylenediamine and guanidine hydrochloride were characterized by 13C NMR, ultracentrifugation, and capillary viscosimetry techniques. It was found that OHMG hydrochloride has 0.16 – 1.08 branching points per molecule. Number-average molecular weights M n and weight-average molecular weights M w were calculated from 13C NMR and ultracentrifugation data. A comparative analysis of these characteristics shows that the synthesized oligomers have a wide molecular-weight distribution (M w /M n = 5.4 – 9.3).

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.

The reaction of fluorobenzene with urotropine in trifluoroacetic acid (TFAA) at high pressures and temperatures affords predominantly fluorobenzaldehydes andN-(fluorophenylmethyl)trifluoroacetamides. The yields of these products depend considerably on the reaction conditions. The rates of their formation have the maximum values at the momemt of the phase transition (PT) of TFAA. A new efficient cyclic (dynamic) regime is proposed for the synthesis at high pressures. The regime involves periodically occurring PT of the solvent. The change in the relative rate of product formation with the degree of fluorobenzene conversion is wave-like.

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.

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.

Condensation of aromatic aldehydes (I)-(XX) with EtNO2 and n-PrNO2 in AcOH in the presence of AcONH4 or i-BuNH2 gives primarilyω-nitrostyrenes (Ia, b)-(XXa, b) and small quantities of nitriles (Ic)-(XXc), oximes (Id)-(XXd), and ketones (Ie, f)-(XXe, f). The yields of (Ia, b)-(XXa, b) at P=1 atm are higher for acceptor substituents on the aromatic ring whereas at P=10 kbar, they are higher for donor substituents. High pressures suppress the formation of (Ic-f)-(XXc-f) and the Z-isomers of (Ia, b)-(XXa, b). The high pressure technique is especially useful in the preparation of donor-substituted (Ia, b)-(XXa, b) which are intermediates in the synthesis of the psychotropic β-phenylethylamines.

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.

The interaction of thiazolo[4,5-e][1,2,4]triazines with bicyclo[2.2.1]heptadiene at a high pressure (up to 15 kbar) results in the corresponding thiazolo[4,5-b]pyridines, and this is the key step of a new approach to fused pyridines based on the tandem S N H − S N H reactions on the 1,2,4-triazine ring.