Disodium C12-15 pareth sulfosuccinate is a substance which is used in cosmetic formulations. The substance acts as surfactant, skin caring and skin cleansing.
Succinates are salts/esters of succinic acid.
The polyoxyethylene ethers of synthetic fatty alcohols are called "pareth" (for comparison see: laurethe as polyoxyethylene ether of lauryl alcohol; steareth as polyoxyethylene ether of stearyl alcohol or here as C12-C15 alcohol mixtures).