The salt is quite insoluble in H2O but can be converted to the free base which is recrystallised from H2O and converted to the sulfate by addition of the required amount of H2SO4. The hydrochloride has m 300-305o(dec) and can be used to prepare the sulfate by addition of H2SO4; it is more soluble than the sulfate. The perchlorate has m 252-254o. The free base has max at 260nm (log 4.24) in 0.1M HCl. [Bogert & Davidson J Am Chem Soc 86 1668 1933, Bredereck et al. Chem Ber 86 850 1953, Sherman & Taylor Org Synth Coll Vol IV 247 1963, Barlin & Pfleiderer J Chem Soc (B) 1425 1971, Beilstein 25 II 382.]