The series of acetylenic carbamates was extended with emphasis 011 the N-cycloaliphatic derivatives. The N-cycloaliphatics had much less cell culture cytotoxicity and neurotoxicity as determined by intrathecal studies~ II dogs than the NHz compounds, even though their acutcb toxicities were about the same. 11Iost of the N-cycloaliphatic compounds exhibited ant it umor activity.
