The aldehyde crystallises as light yellow plates from ethyl acetate. The UV has max 227 and 327.5nm in cyclohexane. The acetyl derivative has m 122o (from EtOH) and the oxime has m 195o (yellow-brown plates from EtOH). [Beilstein 14 H 28, 14 I 359, 14 II 21, 14 III 53, 14 IV 46.]