Complex sentence: Isoprene chains are commonly found in numerous biologically active oligomers such as Vitamin A. Similarly, natural rubber is composed of linear polyisoprene chains of very high molecular weight and other natural molecules.
Split into simpler sentences: Isoprene chains are commonly found in numerous biologically active oligomers such as Vitamin A. Similarly, natural rubber is polyisoprene. It is composed of linear polyisoprene chains of very high molecular weight and other natural molecules.