| 摘要 |
Compounds are disclosed of formula <CHEM> Where R<1> is halogen, C1-4 alkyl, C1-4 alkoxy, hydroxyl, cyano, nitro and -NR<3>R<4> where R<3> and R<4> is each a hydrogen atom or C1-4 alkyl, and R<2> is hydrogen or a substituent as defined for R<1>. Process for the preparation of the compounds are described. |
