A new germacrane-type sesquiterpenoid, menelloide E (1), and a new cembrane-type diterpenoid, lobocrassin F (2), were isolated from the octocorals Menella sp. and Lobophytum crassum, respectively. The structures of terpenoids 1 and 2 were determined by spectroscopic and chemical methods and compound 2 was found to display a significant inhibitory effect on the release of elastase by human neutr...

A novel cytotoxic diterpenoid, chabrolin A (1) (possessing an unprecedented terpenoid skeleton), as well as three new cytotoxic sesquiterpenoids, parathyrsoidins E-G (2-4), were isolated by cytotoxicity-guided fractionation from soft corals Nephtheachabroli and Paralemnalia thyrsoides. The structures of the new compounds were determined by extensive analysis of spectroscopic data.

The structure of iso-grayanotoxin II, a new diterpenoid from Leucothoe grayana MAX., has been determined as 3 beta,5 beta,6 beta,14 beta,16 alpha-pentahydroxygrayanotox-9(10)-ene by spectroscopic and X-ray crystallographic analysis. The lethal dosage level of iso-grayanotoxin II in mice was lower than that of grayanotoxin III.

The methanol extract of Brazilian propolis was fractionated by HPLC, based on HuH13 (human hepatocellular carcinoma) cell cytotoxicity assay. Two isomers of diterpenoid with a molecular formula of C20H30O3 (MW: 318.46) were isolated. The structures of these colorless compounds were determined as clerodane diterpenoids (I, 15-oxo-3, 13Z-kolavadien-17-oic acid; II, 15-oxo-3Z, 13E-kolavadien-17-oi...

This paper summarizes some of our recent research on diterpenoid and norditerpenoid alkaloids. Structures for delatisine, vakhmatine, vakhmadine, ajabicine, tangirine, septatisine, andersobine, and deacetylheterophylloidine are discussed. A novel furanohetisine-type alkaloid isolated from the seeds of Delphinium elafum L. is delatisine (1). The 1% nmr spectrum revealed twenty carbons, none of w...

The title compound, C(26)H(34)O(9), a natural ent-kaurane diterpenoid, is composed of four rings with the expected cis and trans junctions. In the crystal structure, the mol-ecules stack along the a axis and are linked together by inter-molecular O-H⋯O hydrogen bonds.

Four new diterpenoid alkaloids: tiantaishansine (1), tiantaishannine (2), tiantaishanmine (3), and tiantaishandine (4) have been isolated from the roots of Delphinium tiantaishan. Their structures were elucidated by chemical evidence and spectral analyses, including ESI-MS, HR-EI-MS, 1D- and 2D-NMR.