Abstract A class of anti-secretory, anti-ulcer and cytoprotective agents, the substituted (E)-4- phenyl and heteroaryl-4-oxo-2-butenoic acids, is described. This chemical structure is not related to those of any known anti-cholinergic drugs, histamine H 2-receptor antagonists or prostaglandins. Five compounds, 4-(2-methoxyphenyl)-15, 4-(4-methoxyphenyl)-22, 4-(3, 4- dimethoxyphenyl)-32, 4-(3, 4, 5-trimethoxyphenyl)-40, and 4-(2-furanyl)-4-oxo-2-butenoic ...