Determination of stereoselective interaction between enantiomers of chiral gamma-aryl-1H-1,2,4-triazole derivatives and Penicillium digitatum.

A series of chiral gamma-aryl-1H-1,2,4-triazole derivatives has been synthesized and the respective analogues have been tested for their inhibitory activities against Penicillium digitatum (P. digitatum). In vitro experiments were indicative of a strong inhibitory effect of all of the compounds on P. digitatum, and seven of the compounds 5 exhibited better inhibition than the commercial fungicides triadimefon and triadimenol. The respective pairs of enantiomers showed significantly different inhibitory activities, most notably in the case of 5g-R and 5g-S, for which a 230-fold difference was observed. These observations suggest that P. digitatum discriminates the enantiomers and that the R enantiomer better fits the active site of cytochrome P450.