In the study of the effect of replacing the sulfone group in certain predominantly tuberculostatic sulfones by the aromatic type electronattracting2 cyclopropane group, we recently reported3 that 1-(2-amino-4-thiazolyl)-2-(4-amino-phenyl)-cyclopropane exhibits a low in vitro tuberculostatic activity. Since bacteriostasis was still produced by 1, 1, l-trichloro- 2, 2-bis-(4-aminophen-y1)-ethane4 at a dilution of 1 X it appeared desirable to prepare an ...