Aromatic sulphides, sulphoxides, and sulphones as larvicides for Culex pipiens moleatus and Aedes caspius (Diptera: Culicidae)

The toxicities of 36 differently substituted sulphides, sulphoxides, and sulphones toward the larvae of Culex pipiens molestus Forskal and Aedes caspius (Pallas) were studied and compared with those of four of the commonly used standards. The nitro group was a powerful toxiphoric group; the biological activity was increased in the presence OCH3, COOH, or Br substituents. In all cases, the sulphones are more toxic than their corresponding sulphides. Eighteen of the compounds had LC50s less than 1.0 ppm