Synthesis of New Peptidyl Imidazodithi(and -thiadi)azoles as Potential Fungicides

Article abstract of DOI:10.1021/jf00057a038

(4-Oxo-3-phenyl-2-thioxoimidazolidin-5-yl)N-aryldithiocarbamates IVa,b obtained by the reaction of 5-bromo-3-phenyl-2-thiohydantoin (II) and ammonium N-aryldithiocarbamates IIIa,b underwent chemoselective intramolecular heterocylizations with iodine and SOCl2 to yield 2-(arylimino)-6-phenyl-5-thioxoperhydroimidazo<1,5-d><1,3,4>dithiazole-7-thiones Va,b and 3,6-diaryl-2,5-dithiox-operhydroimidazo<5,1-b><1,3,4>thiadiazol-7-ones VIa,b, respectively.Compounds Va,b and VIa,b were converted into the corresponding 2- and 3-peptidyl derivatives IXa-d and Xa-d.Representative copmpounds IXa,b and Xa,b on dethio-oxygenation furnished the corresponding diones XIa,b and triones XIIa,b.Fungitoxicities of compounds IV-VII and IX-XII were evaluated in vitro against Alternaria solani and Fusarium oxysporum.Some of the compounds displayed activities comparable with that of the commercial fungicide Dithane M-45.Structure-activity relationships for the tested compounds are discussed.Keywords: Imidazodithi- and -thiadiazoles; peptidyl heterocycles; fungicides