5′,6′-Dehydroguiachrysine and 5′,6′-dehydroguiaflavine, two curarizing quaternary indole alkaloids from the stem bark of Strychnos guianensis

5′,6′-Dehydroguiachrysine and 5′,6′-dehydroguiaflavine, two curarizing quaternary indole alkaloids from the stem bark of Strychnos guianensis 5′,6′-Dehydroguiachrysine and 5′,6′-dehydroguiaflavine, two curarizing quaternary indole alkaloids from the stem bark of Strychnos guianensis Quaternary indole alkaloids from the stem bark of Strychnos guianensis Quaternary indole alkaloids from the stem bark of Strychnos guianensis Guiaflavine, a New Bisindole Quaternary Alkaloid from the Stem Bark of<i>Strychnos</i><i>g</i><i>uianensis</i> Guiaflavine, a New Bisindole Quaternary Alkaloid from the Stem Bark of<i>Strychnos</i><i>g</i><i>uianensis</i> Guianensine, a zwitterionic alkaloid from Strychnos guianensis Some New Decussine-Type Alkaloids From Strychnos decussata, Strychnos dale and Strychnos elaecocarpa 3′,4′,5′,6′ Tetradehydrolongicaudatine Y, an anhydronium base from Strychnos usambarensis La strychnoxanthine, un alcaloïde monoterpénique d'un nouveau type isolé à partir du Strychnos gossweileri