Synthesis and Herbicidal Activity of 1,3-Dimethyl-4-Acyl-Pyrazol-5-yl Carbamates

1,3-Dimethyl-4-Acyl-Pyrazol-5-yl Carbamates의 합성과 제초활성

1,3-Dimethyl-4-acyl-5-hydroxypyrazoles were treated with methyl isocyanate to give corresponding carbamates. They were 1,3-dimethyl-4-benzoyl-pyrazol-5-yl N-methylcarbamate(V), 1, 3-dimethyl-4-(2-chlorobenzoyl)-pyrazol-5-y1 N-methyl-carbamate(VI), and 1, 3-dimethyl-4-(2,4-dichlorobenzoy1)-pyrazol-5-yl N-methyl-carbamate(VII). The structures of the compounds were fully identified by UV, IR, $^{1}H-NMR$ and $^{13}C-NMR$. The synthesized carbamate compounds were tested for the phytotoxicity on the seed germination and the seedling growth of rice, radish, green-pea and turf grass. At 50ppm concentraction, the germination of seeds was not significantly affected. At higher concentraction, however, phytotoxic tendency on the seed germination and seedling growth was observed. In addition, these compounds were less phytotoxic to rice and turf seedlings as compared with radish and green pea seedlings.

1,3-Dimethyl-4-acyl-5-hydroxypyrazoles와 methylisocyanate로 부터 제초활성이 있는 1,3-dimethyl-4-acy1-pyrazol-5-yl-N-methylcarbamate 유도체를 합성하였다. 이 화합물들의 구조가 IR, UV, $^{1}H-NMR$, $^{13}C-NMR$ 등의 기기분석에 의해 1,3-dimethyl-4-be-nzoyl-pyrazol-5-yl-N-methylcarbamate(V), 1, 3-dimethyl-4-(2-chlorobenzoyl)-pyrazo1-5-yl-N-methylcarbamate(VI) 그리고 1,3-dimethyl-4-(2,4-dichlorobenzoy1)-pyrazo1-5-yl-N-methylcarbamate(VII) 임이 확인되었다. 이 합성 화합물들의 처리에 의한 벼, 무우, 녹두 및 물잔디 종자의 발아 및 생육에 미치는 phytotoxicity를 조사한 결과는 다음과 같다. 일반적으로 4-acyl-pyrazol-5-yl-N-methylcarbamate 화합물들의 저농도(50ppm)에서는 식물종자의 발아에 큰 영향을 주지 않았으며, 농도가 증가할수록 종자의 발아와 생육을 억제하는 경향이었다. 그들은 벼와 물잔디의 줄기의 생육에는 크게 영향을 주지 않았으며, 녹두와 무우의 생육에는 강하게 억제하는 현상을 나타내었다.