Antibacterially active hexamethylene-bis-biguanides

There are disclosed new hexamethylene-bis-biguanides having antibacterial activity, and two processes for the preparation thereof. The new compounds have the general formula wherein R represents H, and R' represents an hexyl or pentyl group being substituted with one or two methyl groups, or represents a cycloalkyl group having more than 6 carbon atoms, a lower-alkyl-cycloalkyl group or a cycloalkyl-lower-alkyl group, or R and R' together with the adjacent nitrogen atom represent an azabicyclo(3,2,2)-nonane double ring.