DUAL ANTAGONISTS OF PLATELET-ACTIVATING-FACTOR AND HISTAMINE .2. PYRIDINE RING SUBSTITUTION OF N-ACETYL-4-(8-CHLORO-5,6-DIHYDRO-11H-BENZO[5,6]CYCLOHEPTA[1,2-B]PYRIDIN-11-YLIDENE)PIPERIDINES

A series of pyridine ring substituted 1-acetyl-4-(8-chloro-5,6-dihydro-11H-benzo[5,6] cyclohepta[1,2-b]pyridin-11-ylidene)piperidines which are antagonists of both PAF and histamine were prepared by one of three different methods. Analogs with substitutents at C-3 were found to be the best dual antagonists among their corresponding regioisomers. Analogs with an electron donating substituent at the C-3 position are generally better antagonists of both PAF and histamine than analogs with electron withdrawing groups.