Synthesis of New 2,4-Diimino-1,3-thiazoles and the Structure Determination

For the purpose of developing new agrochemical fungicides, compound 2 possessing 1,3-thiazole scaffold as well as urea moiety in the structure was designed through molecular modification of lead compound, 2-imino-1,3-thiazoline based on isosterism. The reaction of N-methylthiouea 5 and bromoacetonitrile in ethanol gave 2,4-diimino-1,3-thiazole 4 regioselectively, which was treated with phenyl isocyanates to give the corresponding 7 which is tautomer of 2. The structural assignment of 7 was confirmed by various spectra($^1H$ NMR, $^{13}C$ NMR, FT-IR, HRMS), and X-ray crystallographic data. Compound 8 which is a structural isomer of 7 was formed through thermodynamically unstable intermediate 2,4-diimino-1,3-thiazole 6.

새로운 2,4-Diimino-1,3-thiazoles 유도체의 합성과 구조 결정

신농약 개발을 목적으로 isosterism 이론을 근거로 하여 선도화합물, 2-imino-1,3-thiazoline의 분자 수정을 통하여 분자내에 1,3-thiazole과 urea기가 포함된 새로운 화합물 2를 디자인하였다. N-Methylthiourea 5와 bromoacetonitrile을 에탄올 용액 중에서 반응시켜 위치 선택적으로 생성된 2,4-diimino-1,3-thiazole 4를 phenylisocyanate 유도체와 반응하여 화합물 2의 tautomer인 7을 얻었고 이것의 구조를 여러 가지 스펙트럼($^1H$ NMR, $^{13}C$ NMR, FT-IR, HRMS)과 X-ray 결정 데이터로부터 확인하였다. 화합물 7의 구조이성질체 8은 열역학적으로 불안정한 중간체 2,4-diimino-1,3-thiazole 6을 통하여 생성되었다.