Sesquiterpene derivatives

Separation methods, multichromato-graphic la 56 Serine la 246,356 lb 132 Serotonin la 70,76,239,240,262,355, 380 lb 37-39,231,243,348 Serotonin metabolites lb 327 Serum lipids la 89 Serum proteins la 74 Sesquiterpene derivatives lb 239,446 Sesquiterpene esters lb 239 Sesquiterpene glucosides la 327 Sesquiterpene lactones lb 448 Sevin lb 387-389 Si 50 000, specific surface area la 91 Silica gel, caffeine-impregnated la 85 -, surface modified la 3 Silica gel 60, specific surface area la 91... 

Cyperus rotundus L. is a weedy species, native to India, but widely distributed in countries on the Pacific Rim and islands in the Pacific Basin. Commonly referred to as purple nut sedge, it has been known in the Hawaiian Islands since the middle of the nineteenth century. In addition to its weedy nature, the taxon has attracted attention because of the antifebrile activity of its rhizomes. Chemical studies have disclosed the presence of several sesquiterpene derivatives, some of which have been implicated in the plant s medicinal use (cyperene and cyperinerol) (Wagner et ah, 1990, p. 1399). Our interest in this species is the existence of several chemotypes with interesting patterns of occurrence involving Pacific Rim countries and several oceanic islands, including the Hawaiian Islands, islands in the southern Pacific, and the Philippines. 

Fig. 6.4 Compounds 536-541, sesquiterpene derivatives from Cyperus, the nut sedge...

Table 6.1 Distribution of sesquiterpene derivatives in populations of Cyperus rotundas (from Komai and Tang, 1989)...

Killday, K.B. Longley, R. McCarthy, P.J. Pomponi,S.A. Wright, A.E. Neale, R.F. Sills, M.A. (1993) Sesquiterpene-derived metabolites from the deep water marine sponge Poecillastra sollasi. J. Nat. Prod., 56, 500-7. 

Davyt D, Fernandez R, Suescun L, Mombru AW, Saldana J, Dominguez L, Coll J, Fujii MT, Manta E (2001) New Sesquiterpene Derivatives from the Red Alga Laurencia scoparia. Isolation, Structure Determination, and Anthelmintic Activity. J Nat Prod 64 1552... 

Finally, it is worth noting how many of the sesquiterpene derivatives described above are found in plants belonging to the daisy family, the Compositae/Asteraceae. Whilst sesquiterpenes are by no means restricted to this family, the Compositae/Asteraceae undoubtedly provides a very rich source. 

Sukpondma, Y., Rukachaisirikul, V. and Phongpaichit, S. (2005) Xanthone and sesquiterpene derivatives from the fruits of Garcinia scortechinii. Journal of Natural Products 68(7), 1010-101 7. 

Zhao WM, Ye QH (2002) New Alloaromadendrane, Cadinene and Cyclocopacamphane Type Sesquiterpene Derivatives and Bibenzyls from Dendrobium nobile. Planta Med 68 723... 

The juvenile hormone, which is secreted from a little appendage under the brain (corporus allatum), determines the result of ecdysis, defined as molting of the outer cuticular layer of the body. Four or more chemically related sesquiterpene derivatives constitute the natural hormones. They are synthesized through many steps from acetyl coenzyme A (CoA) via mevalonate and are also found in crustaceans. The JH receptor belongs to the basic helix-loop-helix (bHLH)-PAS family of transcriptional regulators described in textbooks of molecular biology (Alberts et al., 2002). 

Deliberate dehydrogenation of natural hydroazulenes and other sesquiterpene derivatives, sometimes after preceding dehydration, hydrogenation, and reduction, has been the first synthetic path to azulenes (55FCF(3)334, p. 355 59MI2, p. 301). Similar reactions yielded... 

It is worth noting that Lactarius sesquiterpenes derived from velutinal esters (7.28, 7.30) have the same configuration of the related... 

Classification Sesquiterpene derived from essential oils Empirical C15H26... 

Fig. 21.8 (a b). Sesquiterpenes derived from a 2-F-6- -famesyl pyrophosphate precursor. 

Another example of a sesquiterpene-derived insect juvenile hormone is that of the giant silkworm moth, Hyalophora cecropia (Fig. 21.18). Several juvenile hormone mimics have been found in plants (Bowers, 1985,1991,1992 Fraga, 1991 Menn and Beroza, 1972). 

The rhizomes of Nuphar japonicum and N. luteum (Nymphaeaceae) contain sesquiterpene-derived alkaloids that possess a quinolizidine nucleus (Howard and Michael, 1986). These compounds are based on a C15 skeleton of which part has been elaborated into a 3-substituted furan (Howard and Michael, 1986) (Fig. 36.4). 

A daucane-type sesquiterpene derivative, lancerroldiol p-hydroxybenzoate (44, was hydrogenated with cultured suspension cells of the liverwort M. polymorpha to give 3,4-dihydrolancerodiol (447) (Hegazy et al., 2005) (Figure 20.129). 

The diterpenes are discussed in connection with the mono- and sesquiterpene derivatives with which they are closely related according to modern ideas of biosynthesis. Brieskorn s team [24, 24 a] has studied the bitter tasting picrosalvin in Salvia species. It is a diterpene-o-diphenol lactone [24 a] which occurs also in other Labiatae. Nicholas [180] has worked likewise on Salvia sclarea and utilised successfully two-dimensional TLC on sihea gel G layers. He used ethyl acetate as solvent and was able to justify the hypothesis about the incorporation of into sclareol. 

---