| Number | Date | Country | Kind | 
|---|---|---|---|
| 2-081762 | Mar 1990 | JPX | 
| Number | Name | Date | Kind | 
|---|---|---|---|
| 4235773 | Huhne et al. | Nov 1980 | |
| 4591634 | Herd et al. | May 1986 | |
| 4624708 | Solodar | Nov 1986 | 
| Number | Date | Country | 
|---|---|---|
| 2255652 | May 1973 | DEX | 
| 2401594 | Sep 1974 | DEX | 
| 2201978 | Sep 1987 | JPX | 
| 1327914 | Jun 1971 | GBX | 
| 1417428 | Nov 1972 | GBX | 
| Entry | 
|---|
| Chem. Abs. vol. 95, 188627y (1981). | 
| Chem Abs. vol. 106, 19949v (1987)*(=JP 61 51064 as cited above). |