| Number | Date | Country | Kind |
|---|---|---|---|
| 3711268 | Apr 1987 | DEX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4048327 | Karrer | Sep 1977 | |
| 4080470 | Karrer | Mar 1978 | |
| 4125139 | Fischer et al. | Jul 1980 | |
| 4166735 | Pilgram et al. | Sep 1979 | |
| 4309433 | Hirai et al. | Jan 1982 | |
| 4859706 | Buerstinghaus et al. | Aug 1989 |
| Number | Date | Country |
|---|---|---|
| 0004334 | Mar 1979 | EPX |
| 0169169 | Jan 1986 | EPX |
| 2633069 | Feb 1977 | DEX |
| 2637395 | Feb 1977 | DEX |
| 3211988 | Oct 1982 | DEX |
| Entry |
|---|
| Chemical Abstracts; 109: 376176, Aug. 1, 1988. |
| European Search Report. |