Cyclo­(alanine-4-hydroxy­proline)

The title compound, 2-hydroxy-6-methyl-1,2,3,5,6,7,8,8a-octa­hydro-7-aza­indolizine-5,8-dione, C₈H₁₂N₂O₂, is bicyclic. The six-membered ring has a boat configuration. The five-membered ring shares one of the prow points and is hinged towards the open part of the boat. Together the rings appear to adopt a slight dish shape. The methyl group is on the open-dish side and the hydroxyl group is trans to it. Hydro­gen bonds in the crystal knit mol­ecules into corrugated layers.