Di-nor- and 17-nor-pimaranes from Icacina trichantha

Abstract

Six new pimarane derivatives, including two dinor-pimaranes (1, 2), two 17-nor-pimaranes (3, 4), and two 17-nor-(9β-H)-pimaranes (5, 6) were isolated from the tuber of Icacina trichantha. Their structures were elucidated based on spectroscopic and HRMS data. The absolute configurations of 1 and 5 were determined by single-crystal X-ray diffraction, and that of 2 was established by electronic circular dichroism data analysis. Compound 3 possesses a unique C-20 acetal moiety. It is the first report of the isolation of dinor-(9β-H)-pimarane derivatives from Icacina plants. Compounds 5 and 6 showed moderate cytotoxicity against MDA-MB-435, MDA-MB-231, and OVCAR3 cell lines, with IC50 values of 2.91–7.60 µM and 1.48–3.23 µM, respectively.

Discovery of Anticancer Agents of Diverse Natural Origin

“…A key aspect of our group interactions is the prioritization of in vitro- active crude extracts for subsequent activity-guided purification (17, 18). Cytotoxicity assays using selected cancer cell lines are conducted currently mainly at our biological testing core component at UlC [for example, see (54–56)], with some solid tumor and leukemia cancer cell line testing also having been carried out at OSU [for example, see (54, 57, 58)]. Selected target-based in vitro bioassays that have been conducted for the program project include activation of nuclear factor κB (NFκB) (56, 59), mitochondrial transmembrane potential (MTP) (60), and semaphorin 3B assays (61).…”

A Synthetic View on Momilactones and Related 9β-H Pimarane Skeleton Diterpenoids

“…Cytotoxic humirianthone ( 18 ) and 15 R -humirianthol ( 13 ) were found from the lianas in the Suriname rainforest ( Adou et al, 2005 ). The 17- nor -(9 β -H)-pimarane derivates ( Zhao et al, 2015b ), humirianthenolide C ( 23 ), 2 β -hydroxyhumirianthenolide C ( 24 ), icacenone ( 21 ), 7 α -hydroxyicacenone ( 22 ), and icacinlactone E-J ( 19 , 20 , 25 , 26 ) with cytotoxic activities ( Guo et al, 2016 ) were isolated from the tubers of Icacina trichantha ( Zhao et al, 2015a ). 7 α -Hydroxyicacenone ( 22 ), icacenone ( 21 ), and trichanthol B ( 27 ) ( Xu et al, 2021 ) might also be considered for antimicrobial activities ( On'Okoko et al, 1985 ).…”

Investigation of fragmentation pathways of norpimarane diterpenoids by mass spectrometry combined with computational chemistry

“…All isolated norpimarane diterpenoids from the stem of Flickingeria fimbriata were screened for anti‐inflammatory and antitumor activities, and some showed potent inhibitory activities against lipopolysaccharide‐induced TNF‐ α production in RAW264.7 3 . Norpimarane diterpenes are widely distributed in nature; pimarane and norpimarane diterpenes with novel structures were isolated from Icacina trachantha 4–7 …”