| 中文名称 | 英文名称 | CAS号 | 化学式 | 分子量 |
|---|---|---|---|---|
| 4-(2-羟基-5-甲氧基-苯基)-丁酸 | 4-(2-hydroxy-5-methoxy-phenyl)-butyric acid | 55953-85-0 | C11H14O4 | 210.23 |
| —— | 7-Methoxy-4,5-dihydro-1-benzoxepine | 1428941-12-1 | C11H12O2 | 176.215 |
The scope of acid-promoted Fries rearrangements of benzannulated lactones has been examined. The reaction is applicable to seven-membered lactones possessing a sufficiently activated aromatic ring but not to six-membered lactones, and it proceeds in higher yield for diterpenoid lactones than for lower molecular weight lactones. The structures of the 2,6-methano-bridged benzoxocin side products (23), (24), and (25) from rearrangement of the diterpenoid lactone (11) have been assigned.