Solid-Supported Synthesis of Bio-active Carvacrol Compounds Using Microwaves

Abstract

The most abundant and potent natural products having a broad spectrum of biological activity against various pests are terpenoids, especially monoterpenoids. The chemical modification of natural monoterpenoids has been reported to result in modified biological activity. The present work emphasizes the structural modification of carvacrol, a phenolic monoterpenoid, through the synthesis of different ether and ester derivatives that are useful for structure–activity relationship studies to exploit the potent molecules. The carvacrol was reacted with alkyl halides and acid chlorides under microwaves using solid supports such as silica gel, alumina, and fly ash to give ethers and esters, respectively. The synthesis of dimeric ether and ester compounds using dihalides and acid dichlorides was conducted with novel reactions. Additional features of the methodology include very fast reactions, higher yields and purities of the products, and an ecofriendly approach.

Keywords:

• Carvacrol
• Esters
• Ethers
• Microwave Irradiation
• Monoterpenoid
• Solid Supports

ACKNOWLEDGMENT

H. P. Narkhede is thankful to UGC, New Delhi, for providing a teacher fellowship under FIP Scheme of Xth UGC Plan.

Notes

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Presented at the Joint International Conference on Advances in Organic Chemistry and Chemical Biology, IICT, Hyderabad, Jan. 11–12, 2006.

This article is dedicated to Dipesh M. Kotecha, director, Shri. Saraswati Vidya Prasarak Mandal Bhusawal, India.