Tri terpenoids

Clematis armandii Franch. C. heracleifolia DC C. heracleifolia DC var. davidiana (Decaisue ex Verlot) O. Kuntze Mu Tong (Clematis) (stem) Aristolochic acid, saponin akebin, tri terpenoids.25-33 Diuretic, antibacterial. 

Tri terpenoids S. aureus S. capitis S. agalacticae C. albicans C. krusei... 

A variety of alkaloids based on mono-, sesqui-, di-, and tri-terpenoid skeletons have been characterized, but information about their formation in nature is still somewhat sparse. Monoterpene alkaloids are in... 

A new group of secostictanes has been isolated from the lichen Pseudocyphellaria degelii It includes the acid (179), the aldehyde (180), and the acetate (181). G.c.-m.s. provides a powerful tool for the study of the stictane lichen tri-terpenoids. ... 

Several reviews have appeared, on such topics as steroid and terpenoid biogenesis, hemiterpenoid alkaloids,indole alkaloids (monoterpenoids), ophiobolins (sesterterpenoids), sterols in Digitalis, oestrogens, plant tri-terpenoids, and carotenoids. ... 

For smaller quantities of compounds more sensitive inverse detected techniques are available, such as HMQC ( IH-I C one bond correlation via heteronuclear multiple quantum coherence, analogous to HETCOR) and HMBC (proton detected heteronuclear multiple bond correlation spectroscopy) (15). The last provide, in addition to the intraresidue multiple bond correlations, interresidue correlations between the anomeric carbon and the aglycone protons.We follow this general strategy for the structural determination of tri terpenoid saponins of Bupleurum fruticosum (16) andArdisia japonica (9). 

In summary, these important investigations have rationalized the stereochemistry of the 1,3-hydride shift (which transfers a positive centre from C-10 or C-11 at the distal end of FPP to C-1 and so allows initiation of further isomerization or a second cyclization of the Cio or Ci i ring) on the basis of the ring size of the products. This presumably results from fixation of specific conformations of the intermediates on a hypothetical enzyme surface. The larger diversity of structure for sesquiterpenoids than for di- or tri-terpenoids could then reflect the larger conformational flexibility of a Cio or Cii ring (which are often involved in the formation of the former) than of the Ce rings that are usually implicated in the latter. 

In Part I the choice of the most suitable system of classification posed a problem. The two different solutions adopted, one based on structural relationships (monoterpenoids and carotenoids) and the other on biogenetic relationships (sesqui-, di- and tri-terpenoids) in part reflects current practice. 

Tri terpenoids Amyrin, lupeol (TMSi derivatives) Giilz et al., 1987... 

Bioengineering of plant (tri)terpenoids from metabolic engineering of plants to synthetic biology in vivo and in vitro. New Phytol 200 27-43... 

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