This yellow solid is purified by passage through a silica gel column, eluting with *C6H6/Me6CO, evaporating and crystallising the residue from EtOH. The sulfoxide [65373-82-2] has m 133-135o, and the sulfone [22810-82-2] has m 136.5-137o (from EtOH). The dimethylhydrazone has m 111-113o (from BuOH). It forms easily hydrolysable salts. [Nakazumi et al. J Heterocycl Chem 21 193 1984, Chen et al. J Org Chem 51 3282 1986, Van Allen & Reynolds J Heterocycl Chem 8 807 1971, Beilstein 17 I 204, 17 III/IV 5420, 17/10 V 560.]
