Syntheses of Pyrrolo[2,1-b]thiazole Carboxanilides and Their Selective Antifungal Activities against Rice Blast and Wheat Leaf Rust

Pyrrolo[2,1-b]thiazole 카르복스아닐라이드 유도체의 합성 및 그들의 벼 도열병균과 밀 붉은녹병균에 대한 선택적인 항균활성

  • Hahn, Hoh-Gyu (Organic Chemistry Lab, Korea Institute of Science and Technology) ;
  • Nam, Kee-Dal (Organic Chemistry Lab, Korea Institute of Science and Technology) ;
  • Yang, Bum-Seung (Organic Chemistry Lab, Korea Institute of Science and Technology) ;
  • Choe, Gyeong-Ja (Screening Division, Korea Research Institute of Chemical Technology) ;
  • Cho, Kwang-Yun (Screening Division, Korea Research Institute of Chemical Technology) ;
  • Lee, Seon-Woo (Screening Division, Korea Research Institute of Chemical Technology)
  • 한호규 (한국과학기술연구원, 생체과학연구부) ;
  • 남기달 (한국과학기술연구원, 생체과학연구부) ;
  • 양범승 (한국과학기술연구원, 생체과학연구부) ;
  • 최경자 (한국화학연구원 농약스크리닝팀) ;
  • 조광연 (한국화학연구원 농약스크리닝팀) ;
  • Published : 2005.06.30


For development of new agrochemical fungicide, syntheses of pyrrolo[2,1-b]thiazole carboxanilide derivatives 9 and antifungal screening against 6 kinds of plant pathogens were carried out. Functionalization of carboxylic acid on C-2 into carboxanilide in the pyrrolo[2,1-b]thiazole resulted in new 20 candidates, in which are ${\alpha},{\beta}$-unsaturated carboxanilide and methyl groups that are in cis relationship. Treatment of acetoxy-1,4-thiazin with magnesium in refluxing methanol gave pyrrolo[2,1-b]thiazole ethyl ester 4 in higher yield than that of the previous report. Hydrolysis of this compound afforded the corresponding acid 5, which reacted with aniline derivatives in the presence of coupling reagent, DIC to give pyrrolo[2,1-b]thiazole carboxanilides 9. As the result of in vivo antifungal assay of 9 against rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew, some compounds showed selectively antifungal activities against the rice blast and wheat leaf rust.


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