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Updated: Aug 18, 2026

A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
Three new cholinesterase-inhibiting cis-clerodane diterpenoids from Otostegia limbata
Viqar Uddin Ahmad1, Afsar Khan, Umar Farooq
1International Center for Chemical Sciences, H.E.J. Research Institute of Chemistry, University of Karachi, Pakistan. vuahmad@cybernet.pk
Abstract:
Three new tricyclic cis-clerodane type diterpenoids trivially named as limbatolide A (1), limbatolide B (2) and limbatolide C (3) have been isolated from the roots of Otostegia limbata along with two known compounds; oleanic acid and beta-sitosterol. The structure elucidation of the new compounds was based primarily on two-dimensional (2D) NMR techniques. Compounds 1-3 displayed inhibitory potential in a concentration-dependent manner against acetylcholinesterase (AChE; EC 3.1.1.7) and butyrylcholinesterase (BChE; EC 3.1.1.8) enzymes, respectively.
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