Carboxin, structure

Dihydro-2-methyl-l,4-oxathiin-3-carboxanilide (92), known as Carboxin (a fungicide), rearranges to the enamine (93) when refluxed in toluene with / -toluenesulfonic acid. The structural assignment of (93) are made on the basis of crystal x-ray diffraction analysis <84MI 609-02>. 

Extensive studies of structural-activity relationships of carboxamides have been made, particularly in regard to the molecular designs that inhibit carboxin resistant mutants of Ustilago maydis ( l5 These Investigations have shown that... 

On the other hand, G. A. White, etal., showed the existence of negative correlation between carboxin and other carboxin analogs [5], Diethofencarb and benzimidazole are the most famous example of a negatively correlated crossresistance relationship, but those structures are very different. Table 4 shows a 50% inhibitory concentration of succinate-2,6-dichlorophenol reductase activity... 

At that time about ten compounds of this structural class were developmental candidates or had been introduced into the market. Of these carboxin (1) and oxy-carboxin (2) (Table 13.3.1 below) are well known examples that are still used today [2],... 

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