Labdane diterpenoids

Heterocycles in synthesis of drimane sesquiterpenoids from labdane diterpenoids 97IZV896. 

Andrographolide, a labdane-diterpenoid lactone, is the principal bioactive chemical constituent of Andrographis paniculata (Brum. F.) Nees (family Acanthaceae) this prime constituent is mainly concentrated in leaves and can easily be isolated from the crude plant extracts as crystalline... 

Monoalkoxy- and trimethylsilyloxy-l,3 butadienes are electron-rich dienes and have been extensively used in Diels-Alder reactions with electron-poor dienophiles, as already shown in Section 4.1.2 (Schemes 8 and 25). A very recent example is the synthesis of the labdane diterpenoid ( )-erigerol (105), which centers on the key step (102) + (103) (104) (Scheme 28). Diene (102) features, apart firom the... 

The Amherstiae copals have been a rich source of labdane and rearranged labdane diterpenoids. The full description of oliveric acid (7) isolated from one of these, Daniellia oliveri, has appeared. ... 

Forskolin, a labdane diterpenoid, was isolated from the tuberous roots of Coleus forskohlii Briq. (Lami-aceae) [1], C. forskohlii has been used as an important folk medicine in India. Forskolin was found to be an activator of adenylate cyclase [2], leading to an increase of c-AMP, and now a medicine in India, Germany, and Japan. The production of forskolin is completely dependent on the commercial collection of wild and cultivated plants in India. We have already set up the production of monoclonal antibodies (MAbs) against forskolin [3]. The practical application of enzyme-linked immunosorbent assay (ELISA) for the distribution of forskolin contained in clonally propagated plant organs and the quantitative fluctuation of forsko-lin depend on the age of C. forskohlii [4,5]. As an extension of this approach, we present the production of the immunoaffinity column using anti-forskolin MAb and its application [6]. 

As listed in Table 3, the major labdane diterpenoids (2-18) were isolated from turkish species. 

Yoshida, T., Toyota, M., and Asakawa, Y. (1997). Scapaundulins A and B, two novel dimeric labdane diterpenoids, and related compounds from the Japanese liverwort Scapania undulata (L.) Dum. Tetrahedron Lett. 38, 1975-1978. 

Most of the known partial syntheses of drimanes were carried out starting with bi- and tricyclic diterpenoids. However, bicyclic labdane diterpenoids mostly are structurally similar to drimanes. Their only... 

Vlad P.F. and Koltsa M.N. Synthesis and Application of Odorous Compounds from Labdane Diterpenoids, Kishinev, Shtiintsa, 1988 (in Russian). 

M., and Kinghom, A. D (1995) Novel cytotoxic labdane diterpenoids from Neouvaria acuminatissma. Tetrahedron 51, 21-28. 

Two labdane diterpenoids from Nicotiana raimondii Phytochemistry 21 (1982) 395-397. 4835. 

Suzuki, H., A. Noma, and N. Kashima Two labdane diterpenoids from Nicotiana setchelliv, Phytochemishy 22 (1983) 1294-1295. 

At one time, B. gaudichaudiana was taxonomically classified as a varietal form of Baccharis articulata (Lam.) Pers., a widely utilized medicinal plant in several South American countries. However, when B. articulata was examined for its constituents, neither gaudichaudiosides A-F nor any labdane diterpenoids were found to be present. These observation thereby offer chemotaxonomic substantiation for classifying these two taxa as separate species (97). 

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