New pyrazoles; 1,2,4-triazoles; β- and γ-glycols; amidrazones; and amines of the adamantane series have been synthesized. Their activity with respect to smallpox vaccine virus has been studied. High anti-smallpox activity was observed for ethyl-3-(1-adamantyl)-5-(4-methylphenyl)-1H-pyrazole-4-carboxylate (VI) and 1,4-bis(1-adamantyl)-1,4-butanediol (XII).

The antiviral activity of 2-substituted and 2,6-disubstituted quinoline-4-carboxylic acids and their derivatives has been studied against orthopoxviruses on Vero and MK-2 cell cultures. High activity has been found for 2-(1,1′-biphenyl-4-yl)quinoline-4-carboxylic acid.

Изучена противовирусная активность некоторых 2- и 2,6-дизамещенных 4-хинолинкарбоновых кислот и их производных в отношении ортопоксвирусов на культуре клеток Vero и MK-2. Высокая противовирусная активность выявлена для 2-(1,1'-бифенил-4-ил)-4-хинолинкарбоновой кислоты.

New pyrazoles, 1,2,4-triazoles, β- and γ-glycols, amidrazones, and amines of adamantine series have been synthesized and their activity with respect to smallpox vaccine virus has been studied. High anti-smallpox activity was observed for ethyl-3-(1-adamantyl)-5-(4-mathylphenyl)-1H-pyrazole-4-caarboxylate и 1,4-bis(1-adamantyl)-1,4-butanediol.

In this study we examine the possibility that TiO2 nanoparticles and their conjugates can penetrate into cultivated cells without any special transfection procedures. Oligonucleotides and their derivates were conjugated with the TiO2 nanoparticles, which were obtained as colloidal solutions at a concentration of TiO2 0.3M by TiCl4 hydrolysis. The electronic microscopy of various cell cultures (KCT, Vero, and MDCK) treated with nanoparticle solutions (20 µg/µl) showed that nanoparticles could enter the cells and accumulate in the vacuoles and phagosomes and form inclusions in cytoplasm. Thus, we demonstrated the penetration of TiO2 nanoparticles and their oligonucleotide conjugates into intracellular space without any auxiliary operations. Most other researches used electroporation techniques for similar purposes [1, 2, 5].

New synthetic approaches to fluorinated 3-phenyl-1,2,4-benzotriazines for biological testing have been elaborated. 1-(3,4-Difluorophenyl)-3,5-diphenylformazan (IVa) was synthesized via dinitriding of 3,4-difluoroaniline, followed by azo-addition of the resulting azobenzenediazonium chloride with acetaldehyde phenylhydrazone. 6,7-Difluoro-3-phenyl-1,2,4-benzotriazine (Va) was obtained via intramolecular cyclization of formazan IVa in the presence of BF3/AcOH complex. Monofluoro-substituted 6-R-7-fluoro-3-phenyl-1,2,4-benzotriazine derivatives (Vb-Vq) were prepared by substituting fluorine atom with alkoxides in 3,4-difluoronitrobenzene. Conditions for nucleophilic substitution of the second fluorine atom in benzotriazines V have been established. Fluorinated 3-phenyl-1,2,4-benzotriazines have been tested for antiviral and cytotoxic activity on Vero cell cultures and proved to be active against severe diseases caused by smallpox and some other pathogenic viruses.

A new synthetic approaches to fluorinated 3-phenyl-1,2,4-benzotriazines for biological testing has been elaborated. 1-(3,4-Difluorophenyl)-3,5-diphenylformazan (IVa) was synthesized via dinitriding of 3,4-difluoroaniline, followed by azo-addition of the resulting azobenzenediazonium chloride with benzaldehyde phenylhydrazone. 6,7-Difluoro-3-phenyl-1,2,4-benzotriazine was obtained via intramolecular cyclization of formazan IVa in the presence of BF3/AcOH. Monofluoro-substituted 6-R-7-fluoro-3-phenyl-1,2,4-benzotriazine derivatives (V) were prepared by substituting fluorine atom with sodium alkoxides in 3,4-difluoronitrobenzene. Conditions for nucleophilic substitution of the second fluorine atom in benzotriazines V have been found. Fluorinated 3-phenyl-1,2,4-benzotriazines have been tested for antiviral and cytotoxic activity on Vero cell cultures and proved to be active against severe diseases caused by smallpox and some other pathogenic viruses.

Methods for the synthesis of fluorinated pyrido[l,2-a]benzimidazoles have been developed, and a series of such compounds have been obtained and studied for biological activity. In particular, 5,6-difluoro-2-cyanobenzimidazole (II) was synthesized for the first time using the reaction of l,2-diamino-4,5-difluorobenzole (I) with cyanoacetic ether. Pyrido[l,2-a]benzimidazoles (III, IV) were obtained via condensation of benzimidazole II with diethylethoxymethylene malonate and ethyl acetoacetate. The synthesized pyrido[l,2-a]benzimidazoles (III - XIII) were subjected to screening on a culture of Vero cells for antiviral activity and cytotoxicity with respect to ortho -poxviruses that are pathogenic for humans.

Methods for the synthesis of fluorinated pyrido[1,2-a]benzimidazoles have been developed, and a series of such compounds has been obtained and studied for biological activity. In particular, 5,6-difluoro-2-cyanobenzimidazole (II) was synthesized for the first time using the reaction of 1,2-diamino-4,5-difluorobenzole (I) with cyanoacetic ether. Pyrido[1,2-a]benzimidazoles (III, IV) were obtained via condensation of benzimidazole II with diethylethoxymethylene malonate and ethyl acetoacetate. The synthesized pyrido[1,2-a]benzimidazoles (III–XIII) were subjected to screening on a culture of Vero cells for antiviral activity and cytotoxicity with respect to ortho-poxviruses that are pathogenic for humans.

Collase, an enzymatic preparation made from crab hepatopancreas, was used as a dissociative reagent in preparation of primary cell cultures and for detachment of continuous cells from the substrate during reinoculation. Collase was found to increase viable cell harvest by 2 to 2.5 times in comparison with trypsin and had a less detrimental effect on the cells which retained their proliferative activity, morphology, productivity, and sensitivity to viruses.