| 摘要 |
Title cpds. of formula:- (I) (where R1 and R2 are H, halogen NO2, alkoxy, alkyl, or aryl or R1 and R2 together with the adjacent C-atoms stand for a ring system which can be aromatic or cycloaliphatic, can carry further substitis. or can be fused with further ring systems and opt. also contains hetero atoms; R3 is an opt. substd. aromatic residue which can also contain bridge members; and each X is H or two X's together form a bond), which are plant-protection agents, are prepd. by reacting R3(OCN)2 with 2 mol. of corresp. anhydride at 0-250 degrees C. |
