(3β,16E)-16,17-Didehydro-9,17-dimethoxycorynan-16-carboxylic acid methyl ester

Mitragyna ciliata Aubr. et Pellegr. yields this carboline alkaloid which may be purified by crystallization from Et20-light petroleum when it forms small, colourless crystals. The ultraviolet spectrum exhibits absorption maxima at 228 and 292.4 mil with shoulders at 248.8 and 284 mil. The base may be charac_x0002_terized as the perchlorate which forms light yellow prisms from EtOH-Et20, m.p.229-230°C.

[1] Beckett, Shellard, Tackie., J. Pharm. Pharmacal. Suppl., 15, 166T (1963)
[2] Beckett, Tackie., ibid, 15, 267T (1963)
[3] Absolute configuration: Lee, Trager, Beckett., Tetrahedron, 23, 375 (1967)
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