| Number | Date | Country | Kind |
|---|---|---|---|
| 9022790 | Oct 1990 | GBX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4921958 | Abou-Gharbia et al. | May 1990 | |
| 4988814 | Abou-Gharbia et al. | Jan 1991 | |
| 5169845 | Cliffe et al. | Dec 1992 |
| Number | Date | Country |
|---|---|---|
| 2227018 | Apr 1989 | GBX |
| Entry |
|---|
| March, Advanced Organic Chemistry (New York, McGraw-Hill Books, 1987) pp. 879-880. |