Baeocystin, also known as norpsilocybin or 4-phosphoryloxy-N-methyltryptamine (4-PO-NMT), is a zwitterionic alkaloid of the tryptamine family and an analogue of psilocybin (4-PO-DMT). It is found as a minor compound in most psilocybin mushrooms together with psilocybin, psilocin (4-HO-DMT), norbaeocystin (4-PO-T), and aeruginascin (4-PO-TMT). The compound is the N-demethylated derivative of psilocybin and the 4-phosphorylated derivative of norpsilocin (4-HO-NMT).