Phytochemical investigation of the chloroform extract of Tinospora cordifolia yielded a new clerodane diterpenoid tincordin along with tinosporide, 8-hydroxytinosporide, columbin, 8-hydroxycolumbin and 10-hydroxycolumbin. The structure of the new compound was elucidated comprehensively using 1D and 2D NMR methods. All major clerodane diterpenoids isolated were tested for their efficacy as insec...

Five new 13,14-epoxybriarane diterpenoids, briarenolides U-Y (1-5), were isolated from the octocoral Briareum sp. The structures of briaranes 1-5 were elucidated by spectroscopic methods. Briarenolides U-Y (1-5) were found to significantly inhibit the expression of the pro-inflammatory inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein of the lipopolysaccharide (LPS)-st...

This review covers recently-published experimental information on the biosynthesis of terpenoids in the range C5-C25. In addition to sections on the mevalonate and mevalonate-independent (deoxyxylulose phosphate) pathways, the review considers in turn hemiterpenoids, polyprenyl diphosphate synthases, monoterpenoids, sesquiterpenoids, diterpenoids, and sesterterpenoids. The literature from Janua...

[reaction: see text] A general approach to the tricyclic core of the icetexane natural products via the cycloisomerization of alkynyl indenes using GaCl(3) is presented. This strategy provides an efficient synthesis of the natural product salviasperanol and sets the stage for access to other members of this family of diterpenoids.

Phytochemical investigation of a hexane extract of the aerial parts of Plectranthus ornatus yielded three new neoclerodane diterpenoids (1-3), two labdane diterpenes (4 and 5) obtained for the first time as natural products, and several previously known substances. The structures and relative stereochemistry of 1-5 were established mainly on the basis of NMR spectroscopic studies and by compari...