Six undescribed naturally occurring abietane-O-abietane dimers (squamabietenols A-F) together with one 3,4-seco-totarane-type, a pimarane-type, and 17 related known mono-/dimeric diterpenoids were isolated and characterized from the needles and twigs of the ornamental conifer Juniperus squamata. The undescribed structures and their absolute configurations were established by extensive spectroscopic methods, GIAO NMR calculations with DP4+ probability analyses, and ECD calculations. Squamabietenols A and B showed significant inhibitory effects against ATP-citrate lyase (ACL, a novel drug target for hyperlipidemia and other metabolic disorders), with IC values of 8.
View Article and Find Full Text PDFA phytochemical investigation on the MeOH extract of the leaves and twigs of the endangered conifer Torreya jackii Chun led to the isolation and characterization of 21 structurally diverse diterpenoids. Among them, six are previously undescribed, including four abietane-type (torreyins A-D, resp.) and two labdane-type diterpenoids (torreyins E and F).
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