Minor Alkaloids of Corydalis bulbosa, Structure of Bulbodione

Abstract

As a result of the reinvestigation of the alkaloid content of Corydalis bulbosa (L.) DC. (Papaveraceae), growing in Bulgaria, a new 8,11-dioxoaporphine alkaloid, named bulbodione, together with dihydrosanguinarine, dehydroglaucine, (±)-sinactine, glaucinone and bicucullinine were isolated. These six alkaloids had not been detected in our initial study of the plant. The structure of buldodione was elucidated on the basis of spectral data and confirmed by synthesis of the alkaloid by means of Fremy's radical oxidation of bulbocapnine. The identification of the known alkaloids was obtained from their IR and ¹H-NMR spectral data and by direct comparison with authentic samples.