Synthesis and bioactivity of N-cyclopropanecarboxyl-N′-pyridin-2-yl thiourea derivatives and related fused ring compounds

Abstract Cyclopropanecarboxylic acid or 2,2-dimethyl cyclopropanecarboxylic acid was used as a leading compound for its biological activity. Six new N -(substituted) cyclopropanecarboxyl- N ′-pyridin-2-yl thioureas were prepared. Compound 5 was obtained by oxidizing cyclization of compound 4 in the presence of bromine in chloroform solution. The structures of 4 and 5 were confirmed by 1 H NMR and elemental analysis. The preliminary biological tests indicate that compound 4b and 4e have excellent herbicidal activity, and compound 4c and 4f have excellent fungicidal activity.