title: Pyrrolizidine alkaloid analogues. Preparation of semisynthetic esters of retronecine.
mesh_terms: D004952:Esters / Q000138:chemical synthesis; D008722:Methods; D011763:Pyrrolizidine Alkaloids / Q000138:chemical synthesis*; D013329:Structure-Activity Relationship
chemical_list: D004952:Esters; D011763:Pyrrolizidine Alkaloids