| Number | Date | Country | Kind |
|---|---|---|---|
| 75.04912 | Feb 1975 | FR |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2130989 | Schimmelschmidt | Dec 1935 | |
| 2654778 | Burtner | May 1950 | |
| 3182061 | Goldschmidt | May 1965 | |
| 3754021 | Shen et al. | Aug 1973 |
| Number | Date | Country |
|---|---|---|
| 2,047,806 | Apr 1972 | DT |
| Entry |
|---|
| Fateen et al., J. of Chem. of United Arab Republic, vol. 10, No. 3, pp. 331-338, (1967). |
| Helmut et al., Chem. Abstracts, vol. 78, 3969u, (1973). |