Crystal, molecular and electron structure of (2R,3R,4aS,5S,7R,10aS,10bS)-5-ethyl- 2,3-dimethoxy-2,3,7-trimethyl-decahydro-2H- [1,4]dioxino[2,3-g]indolizin-7-ium iodide hydrate

Abstract

Abstract The title compound, C17H32NO4I・H2O, is chiral molecule with seven stereogenic centres. The absolute configuration was assigned from the synthesis and confirmed by the structure determination. The central six-membered ring of the indolizine moiety and 1,4-dioxane ring adopt a chair conformation, with two atoms displaced by -0.530(3), 0.712(3) and -0.631(2), 0.602(2) Å, respectively, from the plane of the other four atoms. The conformation of the pyrrolidine ring is close to that of a envelope, with the flap atom displaced by -0.600(3) A from the plane through the remaining four atoms. The electron structure was calculated by the semiempirical quantum chemistry method PM3. The crystal structure of compound is stabilized by O-H・・・I and O-H・・・O hydrogen bonds.