Polyunsaturated natural products has attracted the scientists from different disciplines such as chemistry, pharmacology and ecology. These natural products are interested in biological perspective towards treatment of various diseases. This work describes the development of different synthetic strategies of some polyunsaturated natural products derivatives and evaluating their biological activities. Also, the total synthesis of methyl bosseopentaenoate via iterative palladium catalyzed cross couplings was described. Development of a methodology for the semi-reduction of conjugated alkynes was described. The prescribed modified methodology facilitates the synthesis of polyunsaturated fatty acids or compounds which contain polyene framework with E,Z-moiety. This work is useful to synthetic chemists at all levels.