1150 Journal of Medicinal Chemistry, 1974. Vol. 17. No 1 1 Albrecht, et al obtained as described for the dialkylamino aldehydes. The crude aldehyde was purified by column chromatography on 50 g of silica gel (SilicAR cc-7, Mallinckrodt), using EtOAc as eluent, and then characterized by ir (appearance of C= O, 1708 cm-. I). nmr (loss of CH3, 6 3.18; appearance of singlet, 6 10.33. 1 H. CHO), and derivatization.