A series of novel Ivermectin derivatives are synthesized at position 4â-hydroxyl group of oleandrosyl moiety using Dicyclohexyl cabodiimide (DCC) and Dimethylaminopyridine (DMAP). Derivatives synthesized by Steglich Esterification reaction between variety of carboxyl containing potent NSAIDs and 4â- hydroxyl of Ivermectin. Their chemical structures were characterized by means of IR, 1H NMR. These newly synthesized derivatives tested for in vitro anthelmintic activity against earthworms of species Pheretima posthuma. In present work, our aim to synthesize 4â-ester derivatives of Ivermectin with carboxyl containing potent NSAIDs to improve the potency of anthelmintic activity. To develop avermectins modified at the 4â-position, we attempted Steglich Esterification reaction of the 4â-hydroxy derivatives to introduce ester groups in presence of DMAP and DCC. The Steglich Esterification reaction would be useful for esterification between carboxyl and hydroxyl group using dicyclohexylcarbodiimide (DCC) as coupling agent and Dimethylaminopyridine (DMAP) as catalyst. In this letter, we report the synthesis of new 4â-ester derivatives with potent NSAIDs and their biological activities.
