Monomeric, Dimeric, and Trimeric Tropane Alkaloids from Pellacalyx saccardianus.
Zi-Yang ChanPremanand KrishnanSayed Mohammadhossein ModaresiLing-Wei HiiChun-Wai MaiWei-Meng LimChee-Onn LeongYun-Yee LowSoon-Kit WongKien-Thai YongAlyssa Zi-Xin LeongMei-Kee LeeKang-Nee TingKuan-Hon LimPublished in: Journal of natural products (2021)
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.