Synthesis and biological activity of 3‐[(6‐chloropyridin‐3‐yl)methyl]‐6‐substituted‐6,7‐dihydro‐3 H ‐1,2,3‐triazolo[4,5‐ d ]‐pyrimidin‐7‐imines

A series of 3‐[(6‐chloropyridin‐3‐yl)methyl]‐6‐substituted‐6,7‐dihydro‐3 H ‐1,2,3‐triazolo[4,5‐ d ]pyrimidin‐7‐imines were designed and synthesized via a multi‐step sequence using 2‐chloro‐5‐(chloromethyl)‐pyridine as the starting material. Various primary aliphatic amines, hydrazine and hydrazide reacted with 3 to obtain the cyclization products 4 . Their structures were confirmed by 1 H NMR and elemental analyses, some of them were also confirmed by IR, 13 C NMR, MS and single crystal X‐ray diffraction. The preliminary bioassay indicated that some of the target compounds 4 displayed moderate to weak fungicidal activity and insecticidal activity.