Abstract
Condensation of 4-unsubstituted and substituted thiosemicarbazines with α-alkylacetoacetic esters and with amides gave the corresponding thiosemicarbazones and their cyclized products, 3, 4-disubstituted 1-thiocarbamoyl-2H-pyrazolin-5-ones. These products were tested for their preventive and curative activities against rice blast, and 4-hexyl-3-methyl-1-(N-methylthiocarbamoyl)pyrazolin-5-one was found most effective for controlling rice blast.
