1'-Alkylspiro [isochroman-3, 4'-piperidin]-1-ones (2) and 1'-alkylspiro [isochroman-4, 4'-piperidines] (4 and 5) were prepared and examined for analgesic activity. Several of the 4-spiro compounds (3, 4, and 5) were found to have analgesic activity as potent as that of aminopyrine, while the 3-spiro compounds (2) were inactive. Further pharmacological studies revealed that several of these compounds inhibited the histamine release induced by compound 48/80 from isolated rat peritoneal mast cells.
,4'-piperidines] were prepared and examined for their biological activity. Several of the compounds inhibited the compound 48/80 induced histamine release from isolated rat peritoneal mast cells. The structural requirements for this activity in the present series are discussed.