2, 8-Dibenzylcyclooctanone, 2, 4-dibenzyl-3-pentanone, 2-(2-fluorobenzyl)-8-((~-ethoxy-2- fluorobenzyl) cyclooctanone, and 2, 8-bis (2-methylbenzyl) cyclooctanone were found to inhibit pregnancy completely at 50 mg/kg. The MEDioo for 2, 8-dibenzylcyclooctanone in CFl mice was 28 mg/kg while the MEDloo for Sprague-Dawley rats was< 1 mg/kg. These compounds had no effect on male fertility
![1,5-bis[(4-chlorophenyl)methoxy]cyclooctane Structure](https://image.chemsrc.com/caspic/376/53860-19-8.png)