The invention discloses a saturated heterocyclic nitrogen containing caffeic acid derivative separated from nightshades, or pharmacological acceptable salt of the caffeic acid derivative. The compound is a hydroxycholine M receptor antagonist and can be used for treating diseases of spasm, stenocardia, cholecystalgia, renal colic, visceral spasm and the like. An unmarked cell-targeting pharmacological technique is adopted, research on dose-effect relationship displays DMR response signals caused by antagonistic acetylcholine with compound dose dependency and shows that the compound has high hydroxycholine M receptor antagonistic activity. Compared with known M receptor antagonist atropine, scopolamine and the like, the compound is large in structural difference, and selectivity on muscle glands and the nervous system can be expectedly improved; current research shows that a hydroxycholine M receptor is related to diseases of spasm, analgesia, calm, schizophrenia and the like, and an efficient new ligand definite in action target can be provided for the related diseases.