| Number | Date | Country | Kind | 
|---|---|---|---|
| 6163/89 | Nov 1989 | HUX | 
| Number | Name | Date | Kind | 
|---|---|---|---|
| 2352944 | D'Alello | Jul 1944 | |
| 4421753 | Tomcufcik et al. | Dec 1983 | 
| Number | Date | Country | 
|---|---|---|
| 949170 | Feb 1964 | GBX | 
| Entry | 
|---|
| T. Hirata et al., `5-Azapurines and the Structures of Sym-Triazole Intermediates`, Journal of Heterocyclic Chemistry, Feb. 1972; Bd. 9, Nr. 1, Provoh US, pp. 99-106. | 
| Reiter et al., "On Triazoles, XII, etc.", J. Heterocyclic Chem., 24, 1685-1695 (1987). |