OBSERVATIONS ON ADMINISTRATION OF IRIDODIAL-7-14C TO VINCA ROSEA

It has been suggested that iridodial is a biosynthetic intermediate between geraniol and loganin, which is a precursor of the non-tryptophan derived portion of vindoline, catharanthine, ajmalicine, and other indole alkaloids found in Vinca rosea. Iridodial-7-14C was synthesized from ethyl iodide-1-14C and fed to V. rosea plants, which afforded vindoline having negligible activity. It thus seems unlikely that iridodial is a precursor of loganin. © 1969.