Antiimplantation agents: Part II. 1,2-Diaryl-1,2,3,4-tetrahydroisoquinolines

Abstract

1,2-Diaryl-3,4-dihydroisoquinolinium derivatives (5) have been synthesised from N-aryl-N-aroyl-α-phenethylamines (4) and found to exhibit no antiimplantation activity in the rat whereas many of the corresponding tetrahydroisoquinolines (6) are active. Structure-activity relationships have also been studied. 1-(p-Fluorophenyl)-6-methoxy-2-phenyl-1,2,3,4-tetrahydroisoquinoline (6u) and its nor derivative (6v) are very potent, while the onho (6g)and lhemeta(6n) fluoro analogues as well as the des-fluoro derivative (6d) are quite active. Extensive biological tests have been carried out on 6g. The enantiomers(+)-6p.HCl and(-)-6g.HCl of 6n have similar activity profiles as that of 6n showing no separation of antiimplantation and estrogenic properties. Diastereoisomeric 2-(2-methyl-2-phenethyl)-1-phenyl-r,2,3,4-tetrahydrpisqquinolines (13a and 13b) show similar properties, while the tetracyclic derivative 19 is inactive. 2-Phenoxyethyl-l-phenyl-1.2,3,4-tetrahydroisoquinpline (26) shows moderate activity, but (α-phenethyl)-2-phenyl-1,2,3,4-tetrahydroisoquinoline 29 is inactive.