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Updated: Oct 26, 2025

Author Spotlight: Discovering New Alkaloids in Plants with Advanced Mass Spectrometry Techniques
Published on: March 8, 2024
Monomeric, Dimeric, and Trimeric Tropane Alkaloids from Pellacalyx saccardianus
Zi-Yang Chan1, Premanand Krishnan1, Sayed Mohammadhossein Modaresi1
1School of Pharmacy, University of Nottingham Malaysia, Jalan Broga, 43500 Semenyih, Selangor, Malaysia.
Abstract:
Seven new tropane alkaloids, including five monomeric (1-5), one dimeric (6), and one trimeric (7) 3α-nortropane ester, along with two known monomeric nortropane alkaloids (8 and 9), were isolated from the leaves and bark of Pellacalyx saccardianus. Their structures, including the absolute configuration of the enantiomeric pair of (±)-6, were elucidated by comprehensive spectroscopic analyses. Alkaloids 6 and 7 showed cytotoxicity toward human pancreatic cancer cell lines (AsPC-1, BxPC3, PANC-1, and SW1990). Alkaloids 1, 4, and 9 induced a smooth muscle relaxation effect comparable to that of atropine (Emax 106.1 ± 7.5%, 97.0 ± 5.2%, 100.9 ± 1.4%, 111.7 ± 1.7%, respectively) on isolated rat tracheal rings.
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