(1R-cis)-3-(2,2-Dichloroethenyl)-2,2-dimethylcyclopropanecarboxylic acid 1R-cis-Permethric acid 55667-40-8 BRN 4392155 CYCLOPROPANECARBOXYLIC ACID, 3-(2,2-DICHLOROETHENYL)-2,2-DIMETHYL-, (1R-cis)-