STUDIES ON THE METABOLISM OF QUATERNARY PROTOBERBERINE ALKALOIDS IN CELL-CULTURES OF CORYDALIS-PALLIDA VAR TENUIS AND CORYDALIS-INCISA

An lc-apcims procedure was applied towards the identification of metab olites of quaternary protoberberine alkaloids in cultured cells of Cor ydalis species. Interconversions of tetrahydroprotoberberines [3 and 1 0] and protoberberinium salts [1 and 8] and those of cis- and trans-13 -methyltetrahydroprotoberberines [14, 20, 18, 23] and 13-methylprotobe rberinium salts [2 and 9] were demonstrated. The oxidation-reduction p rocess of the C ring of protoberberines was confirmed. The correspondi ng alpha-N-metho sales [4, 11 or 15,and 19] having the B/C-cis ring ju nction were produced from tetrahydroprotoberberines [3, 10] or cis- an d trans-13-methyltetrahydroprotoberberines [14 and 18]. Methylation at C-13 of the protoberberinium salts 1 and 8 afforded the 1 3-methylpro toberberinium salts 2 and 9.