Multiside inhibitors

The majority of fungicidal structures published for material-protection in the last years belong to the group of multiside-inhibitors. Most of them are electrophilically active agents. 

The fungicidal and antibacterial activity is the result of a reaction with nucleophilic components in the microbial cell. The nucleophilic partners are thio-, amino- and amido-groups of amino acids in proteins. A reaction with the nucleophilic group leads to an unspecific enzyme inhibition which results in cell death. See chapter 2. 

The biocidal spectrum of these compounds is generally broader compared to compounds with a specific mechanism. The unspecific action leads in general to a significant decrease in possible resistance (except resistance caused by reduced uptake and detoxification). The selectivity toward different organisms of these intrinsically unspecific compounds results from different transport-mechanisms and differences in the metabolism. The disadvantage is sometimes a higher toxicity toward warm-blooded animals and an increase in the possibility of other toxic effects like sensitization. 

The reactive principle of most multiside-inhibitors found in the last years are activated C-C or C-N-double-bonds, reactive S-N-groups or aldehyde units. 

The class of benzothiophene-2-carboxamid-S,S-dioxides came to the attention of the Bayer research because of their in vitro antifungal activity against a broad range of agro- and material-protection relevant fungi (Elbe et al., 1992 Elbe et al., 1996). 

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