| Number | Name | Date | Kind |
|---|---|---|---|
| 2197846 | Wolff et al. | Apr 1940 | |
| 3883529 | Austin | Dec 1972 | |
| 3956300 | Austin | Aug 1972 | |
| 4237281 | Long | Dec 1980 | |
| 4264507 | Borror | Apr 1981 | |
| 4290950 | Cournoyer et al. | Sep 1981 | |
| 4290951 | Foley et al. | Sep 1981 |
| Number | Date | Country |
|---|---|---|
| 2907437 | Aug 1978 | DEX |
| 5050244 | Oct 1978 | JPX |
| 1423346 | Feb 1972 | GBX |
| 2016631 | Sep 1979 | GBX |
| Entry |
|---|
| Ramanouskas et al., Chem. Abst. vol. 88, Abst. #192734d. |