soft quaternary surface active agents having the formula : ## str1 ## wherein & gt ; n represents a tertiary open chain or cyclic aliphatic amine ; wherein & gt ; n represents an unsaturated amine ; wherein r represents a member selected from the group consisting of a hydrogen atom , a c 1 - c 20 open chain or cyclo alkyl group , a c 1 - c 20 alkoxyalkyl group , a c 1 - c 20 acyloxyalkyl group , a c 1 - c 20 haloalkyl group , a c 1 - c 20 carboxyalkyl group , an aryl group , and a substituted aryl group , whose substituents are selected from the group consisting of a halogen atom , an o -- c 1 - c 4 alkyl group , an o -- c 1 - c 8 acyl group , a nitro group , a carboxyl group , and a carboethoxy group ; wherein r 1 represents a c 9 - c 22 straight or branched alkyl group , a -- n -- ## str2 ## group , wherein r 3 , r 4 , r 5 and r 6 are each selected from the group consisting of a hydrogen atom , a methyl group or an ethyl group , a c 0 - c 22 straight or branched alkyl - n ## str3 ## m ch 3 group , wherein n in each occurrence and m represents an integer of from 0 to 22 , an a - ch 2 ## str4 ## ch 2 - a - ch 3 group , wherein a represents a c 0 - c 22 straight or branched alkyl group as above or a -- group , wherein the p represents an integer of from 0 to 22 , and the residue of any naturally occurring bile acid or synthetic derivative thereof ; and wherein x represents a halogen atom or any other organic or inorganic monovalent anion are disclosed . all compounds encompassed within the above - described generic formulae find use as &# 34 ; soft &# 34 ; antibacterial agents of extremely low toxicity .