(6 S ,7 S ,8 S ,8a S )-6-Ethyl-7,8-dihydroxy-1,5,6,7,8,8a-hexahydroindolizin-3(2 H )-one monohydrate

The absolute configuration of the title compound, C10H17NO3·H2O, was assigned from the synthesis. In the molecular structure, the central six-membered ring of the indolizine moiety adopts a chair conformation, with two atoms displaced by −0.578 (2) and 0.651 (1) Å from the plane of the other four atoms [maximum deviation 0.019 (2) Å] The conformation of the fused oxopyrrolidine ring is close to that of a flat envelope, with the flap atom displaced by 0.294 (1) Å from the plane through the remaining four atoms. In the crystal, one of the hydroxy groups is hydrogen-bonded to two water molecules, while the other hydroxy group exhibits an intermolecular hydrogen bond to the carbonyl O atom, resulting in a chain parallel to the b axis.