title: Further enhancment of analgesic activity: enkephalin analogs with terminal guanidino group.
mesh_terms: D000698:Analgesia; D000818:Animals; D004723:Endorphins / Q000494:pharmacology*; D004745:Enkephalins / Q000138:chemical synthesis / Q000494:pharmacology*; D006146:Guanidines / Q000494:pharmacology*; D006168:Guinea Pigs; D008297:Male; D051379:Mice; D051381:Rats; D013329:Structure-Activity Relationship
chemical_list: D004723:Endorphins; D004745:Enkephalins; D006146:Guanidines