Assessment of the <i>in vitro</i> broad‐spectrum antiviral activity of some selected antitumor organotin complexes

Abstract Eleven antitumor‐active octahedral organotin complexes of the type R 2 SnX 2 L 2 , where R = methyl, ethyl or phenyl, X = chloride or bromide, and L 2 = o ‐phenantholine ((phen), 2‐)2‐(pyridyl)‐benzimidazole (PBI) or two dimethylsulfoxides (2DMSO), were examined for their broad‐spectrum in vitro antiviral activity against a number of DNA and RNA viruses. The DNA viruses included in this study were herpes simplex virus type 1 and type 2, a TK–(thymidine kinase deficient) strain of herpes simplex virus type 1, and vaccinia virus. The RNA viruses were vesicular stomatitis virus, Coxsackie virus type B4, Sindbis virus, Semliki forest virus, parainfluenza virus type 3, and human immunodeficiency virus (HIV). Overall, the complexes showed weak antiviral activity and low selectivity. With the exception of (CH 3 ) 2 SnBr 2 ·PBI and (C 6 H 5 ) 2 SnCl 2 ·2DMSO, all of the complexes were active against one or more of the three strains of herpes simplex viruses. On the other hand, only three complexes, (CH 3 ) 2 SnBr 2 ·PBI, (CH 3 ) 2 SnBr 2 ·phen, and (C 6 H 5 ) 5 SnBr 2 ·PBI, exhibited marginal activity against some of the RNA viruses. None of the complexes was active against vesicular stomatitis or parainfluenza virus. Similarly, there was no inhibitory activity towards HIV‐1‐associated reverse transcriptase or HIV‐1‐induced cytopathogenicity in human T‐lymphocyte MT4 cell cultures at subtoxic concentrations.