| Number | Name | Date | Kind |
|---|---|---|---|
| 3137705 | Prelog et al. | Jun 1964 | |
| 3184510 | Levy | May 1965 |
| Number | Date | Country |
|---|---|---|
| 1517774 | Feb 1968 | FRX |
| 2115812 | Sep 1983 | GBX |
| Entry |
|---|
| Kumar, Yatendra et al., Acta Pharm. Suec., vol. 20, (1983), pp. 349-364. |
| Conant, James Bryant et al., The Chemistry of Organic Compounds, 4th Ed. (1955), MacMillan, publ. p. 335. |