Three neo-clerodane diterpenoids, inermes A, B and 14,15-dihydro-15 beta-methoxy-3-epicaryoptin, have been isolated from the hexane extract of the leaves of Clerodendrum inerme in addition to an epimeric mixture of 14,15-dihydro-15-hydroxy-3-epicaryoptin. Structures of these compounds have been elucidated on the basis of spectral studies.

Three new neoclerodane diterpenoids, salvinorins D-F (4-6), have been isolated from the leaves of Salvia divinorum. The structures were elucidated by chemical and spectroscopic methods, particularly 1D and 2D NMR. A simplified isolation method using chromatography on activated carbon also gave improved yields of the controlled substance salvinorin A (1) and of salvinorin C (3).

Titanium chelate addition of aryl nucleophiles to cyclopropyl aldehyde 6 followed by a tin-catalyzed one-pot retro-aldol, acetalisation and lactonisation sequence afforded cis and trans γ-aryllactone acetals. A γ-furyllactone derived by this approach was further transformed in two steps to model compounds for the oxidised northeastern sectors of selected Pseudopterogorgia diterpenoids.

Three new neoclerodane diterpenoids, divinatorins A-C (7-9), have been isolated from the leaves of Salvia divinorum. The compounds were identified by spectroscopic methods as derivatives of the antibiotic (-)-hardwickiic acid (10), which was also isolated, along with four other known terpenoids. Neither the crude extract nor 7-9 displayed antimicrobial activity.

A concise and diastereoselective route to the angularly fused [5-6-7] tricyclic carbon framework of the steenkrotin-type diterpenoids was reported. The key features of the strategy are based on an intramolecular nitrile oxide/alkene [3 + 2] cycloaddition and a regio-selective aldol/dehydration sequence.

In this study, the biological properties of natural abietane-type diterpenoids with an aromatic C ring are reviewed. An overview of the synthetic studies of this group of abietanes, including dehydroabietic acid, callitrisic acid and ferruginol, is presented. The review contains about 160 references.

Four new briarane-related diterpenoids, designated as briaexcavatins M-P (1-4), were isolated from the cultured octocoral Briareum excavatum. The structures, including the relative configurations of natural products 1-4 were established on the basis of extensive spectral data analysis and by comparison with the spectral data from other known metabolites featuring a briarane carbon skeleton.

Four new cembrane-type diterpenoids, sarcophyolides B-E (1-4), along with 11 known analogues were isolated from the soft coral Sarcophyton elegans. The structures of new compounds 1-4 were established on the basis of spectroscopic analysis and chemical conversion. The new cembranoids sarcophyolides B (1) and lobocrasol were found to exhibit potent inhibition against A2780 human ovarian tumor ce...

Three new neo-clerodane diterpenoids, one C-16 epimeric pair, scutegalerins C and D, and scutegalerin E, together with the known scutaltisin B, were isolated from the acetone extractof the aerial parts of Scutellaria galericulata. The chemical structures of the new compounds were elucidated by spectroscopic techniques and a comparison with data of similar compounds as (13S,16R,19S)-6a-acetoxy-2...