Neo-clerodane

Januario AH, Simone LS, Silvana M, et al. Neo-clerodane diterpenoid, a new metallo-protease snake venom inhibitor from Baccharis trimera (Asteraceae) anti-proteolytic and anti-hemorrhagic properties. Chem Biol Interact 2002 150 243-251. 

Esquivel, G., Calderon, J.S., and Elores, E., A neo-clerodane diterpenoid from Scutellaria seleri-ana, Phytochemistry, 47, 135, 1998. 

New diterpenoids belonging to weo-clerodane type (39), some having an unusual neo-clerodane rearranged skeleton with eight-membered ketone ring (40-44), were recently described126. 

M. S. J. Blaney, W. M. Oxirane-opening reactions of some 6,19-oxygenated 4a,18-epoxy-neo-clerodanes isolated from teucrium. Biogenesis and antifeedant activity of their derivatives. Tetrahedron 1994, 50, 5451-5468. 

E-isolinaridial and E-isolinaridial methylketone are two neo-clerodane diterpenoids isolated from the aerial parts of Linaria saxatilis var. glutinosa (Schrophulariaceae). Benrezzouk et al. evaluated these compounds on multiple inflammation pathways and found that they were not COX-1/COX-2 inhibitors [139]. However, E-isolinaridial and E-isolinaridial methylketone were dual inhibitors against purified phospholipase A2 and 5-lipoxygenase. E-isolinaridial and E-isolinaridial methylketone showed potent inhibition of cell-free 5-LOX enzyme with IC50 values of 0.42 pM and 1.41 pM,... 

Fig. (19). Neo-clerodane diterpenes from Linaria saxatilis var. glutinosa.

The clerodanes are a notable example of feeding deterrents2 and further examples have been discovered recently. The natural insect antifeedant clerodin (100) forms the basis of the name of this type of diterpenes called the neo-clerodane diterpenes. Ateo-clerodanes are compounds with a clerodane skeleton and exactly the same absolute configuration as clerodin. Those that have the opposite absolute configuration are referred to as ent-neo- cl erod an es. 

Four bicyclic type diterpenoids have been reported from Salvia species labdanes, neo-clerodanes and clerodanes, seco-clerodanes, rearranged clerodanes. 

Rearranged neo-clerodanes (117-118) found in S. puberula [106] and S. leucantha [95] respectively, showed a 7/6 A/B ring system while a 6/7 A/B ring system was observed in the three salvigenane diterpenoids (119-121). 

Bruno M, Fazio C, Arnold NA (1996) Neo-clerodane diterpenoids from Scutellaria cypria. Phytochemistry 42 555-557... 

Characteristic constituents from the Baccharis genus, one member of the Compositae, are the neo-clerodane type diterpenes. For example, the aerial parts of B. trinervis, a representative of which is used in South American folk medicine, furnished 24 neo-clerodane type diterpenes, many of them new, e.g., methyltrineracetal, Fig. (1) and epi-methyltrineracetal, Fig. (2) [19],... 

From another Argentinian Baccharis species, B. articulata, three diterpenes of neo-clerodane type, articulin, Fig. (3), articulin acetate and barticulidiol, Fig. (4), together with the known bacchotricuneatin A, Fig. (5), were isolated [22,23],... 

Jakupovic et al. [34] investigated some representatives of the genus Baccharis which grow in Texas and Mexico, and seven new e /-clerodane diterpenoids have been described from Baccharis pteronioides D. C. Novel neo-clerodane diterpenoids were also isolated from the aerial parts of B. genistelloides, which were collected in the area of Sao Paulo and neighbouring states of Brazil [35-37] and from Baccharis scoparia (L.) Sw., a species widespread in the Caribbean Islands [38],... 

Teucrium species are a rich source of neo-clerodane diterpenes which can be used as chemotaxonomic markers for the genus. TTiey possess therapeutic properties and are used as folk medicine in many parts of the world. 

According to Rowe s nomenclature [14], the hydrogen at C-lOa being and methyl at C-5 P(Me-19) indicate clerodane, the reverse en/-clerodane structure. Roger [ 15] assigned en/-/jeo-clerodane for the former and neo-clerodane for the latter type of stmctures. In the present day, clerodane and neo-clerodane names are used commonly. Most of the diterpenoids isolated from Teucrium species have neo-clerodane structures. 

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