(5S,16S,19E)-3,17-Dihydroxy-5,16-cyclo-19,20-didehydrocorynan-16-carboxylic acid methyl ester

An alkaloid isolated from Voacanga chalotiana, this base has [α]²⁰_D + 43.5° ± 4° (MeOH). It forms a methiodide, m.p. 215-6°C; [α]²⁰_D - 12° ± 4° (MeOH); the O,N-diacetyl derivative, m.p. 212-3°C and the O,N-ditosyl compound, m.p. 193-4°C. When heated with mineral acids, the alkaloid gives isovoacarpine, m.p. 227.5-228.5°C, giving an N-acetyl derivative, m.p. 256-7°C.

Denayer-Tournay et al., Bull. Soc. Chim. Belg., 74, 170 (1965)