Crystal and molecular structure of maytoline methiodide

Abstract

X-ray crystal structure analysis of maytoline methiodide has defined the constitution and stereochemistry of maytoline, a novel sesquiterpene alkaloid isolated from Maytenus ovatus Loes. Crystals of the methiodide have space group P2₁ with a= 11·643(3), b= 14·621(2), c= 10·436(2)Å, β= 97·43(1)°, and Z= 2. The structure was solved by the heavy-atom method and the atomic parameters refined by least-squares techniques to R 0·062 for 1626 independent reflections measured by counter diffractometry. The stereochemistry of the nucleus of the molecule is related to that of dihydro-α-agarofuran but the absolute configuration has not been established.