| abstract |
The present invention relates to taking 4-bromo-1-aminonaphthalene (2) as starting material, and CS2 generation aminolysis and hydrazinolysis, obtain 4-bromo-naphthalene-1-yl-thiosemicarbazide (3); 3 in N , under the effect of N-dimethylformamide dimethyl acetal, obtain 4-(4-bromo-naphthalene-1-yl)-4H-1,2,4-triazole-3-thiol (4) ; 4 under the action of methyl chloroacetate, obtain 2-[4-(4-bromo-naphthalene-1-yl)-4H-1,2,4-triazole-3-ylthio]methyl acetate (5 ); 5 is coupled with cyclopropylboronic acid to give 2-[4-(4-cyclopropyl-naphthalen-1-yl)-4H-1,2,4-triazol-3-ylthio]acetic acid The methyl ester (6); 6 was hydrolyzed with NBS bromide and lithium hydroxide to obtain the final compound Lesnida (1). The preparation method is simple and easy, has high yield and good quality, and is convenient for industrialized production. |