Synthesis and Acaricidal Activity of N-(1,3,4-Thiadiazol-2-yl)cyclopropanecarboxamides

「INTRODUCTION」 In our previous paper, we reported the structure-activity relationships of acaricidal N-(1,3,4-thiadiazol-2-yl)carboxamides. 1) In the course of our study, a series of N-(1,3,4-thiadiazol-2-yl)cyclopropanecarboxamides were synthesized and their acaricidal activities were examined. 2) This paper describes the structure-activity relationships of acaricidal N-(1,3,4-thiadiazol-2-yl)cyclopropanecarboxamides. MATERIALS AND METHODS 1. Synthesis of Compounds Melting points were uncorrected. The structures of compounds were confirmed by 1H NMR spectra. 1H NMR spectra were measured on a Varian UNITY 300 spectrometer at 300 MHz using tetramethylsilane as an internal standard. N-(1,3,4-Thiadiazol-2-yl)cyclopropanecarboxamides were synthesized from cyclopropanecarboxylic acids and 2-amino-1,3,4-thiadiazoles (Fig. 1). 2-Amino-5-substituted-1,3,4-thiadiazoles were purchased from commercial sources or synthesized according to the reported procedure. 3, 4) Cyclopropanecarboxylic acids were purchased from commercial sources or synthesized according to the reported procedure. 5, 6)