Diterpenes abietanes

Solldago is a mostly North American genus of about 125 species. It belongs to the Asteraceae (Compositae), a family with a very distinctive chemistry (57, 58). The genus itself contains several different classes of secondary compounds including a number of diterpenes (59). During the 1960 s and 1970 s Anthonsen in Finland, and McCrindle and his coworkers in Canada, isolated about twenty-five different compounds from the roots of Solidago species, mainly clerodanes and labdanes. But in the last five years attention has turned to the aerial parts of the plant and compounds of several other classes of diterpenes, abietanes and kauranes, have been isolated (60-79) (Table II). 

Makinoa crispata (Steph.) Miyake from Japan was shown by Hashimoto et al. (1989) to contain diterpene derivatives of the sort illustrated as [466-469] (see Fig. 5.7 for stractures). More recently, Liu and Wu (1997) reported the presence of the rearranged abietane-type diterpenoid derivative makanin [470] from plant material of M. crispata collected on Taiwan. Of note was the apparent absence of any of these compounds in the Japanese plants. 

Milanova R, M Moore, Y Hirai (1994) Hydroxylation of synthetic abietane diterpenes by Aspergillus and Cunninghamella species novel route to the family of diterpenes isolated from Tripterygium wilfordii. J Nat Prod 5T 882-889. 

Topcu, G. Ulubelen, A. Abietane and rearranged abietane diterpenes from Salvia montbretii. J. Nat. Prod. 1996, 59, 734—737. 

Ikeshiro, Y. Mase, I. Tomita, Y. Abietane-type diterpene quinones from Salvia nippo-nica. Planta Med. 1991, 57, 588. 

Cerqueira, F. Corderio-Da-Silva, A. Gaspar-Marques, C. Simoes, F. Pinto, M. M. M. Nascimento, M. S. J. Effect of abietane diterpenes from Plectranthus grandidentatus on T- and B-lymphocyte proliferation. Bioorg. Med. Chem. 2004, 12, 217-223. 

Yang, Z. Kitano, Y. Chiha, K. Shibata, N. Kurokawa, H. Doi, Y. Arakawa, Y. Tada, M. Synthesis of variously oxidized abietane diterpenes and their antibacterial activities against MRS A and VRE. Bioorg. Med. Chem. 2001, 9, 347-356. 

In a series of publications over the past few years, the group of Barriault has reported on microwave-assisted tandem oxy-Cope/Claisen/ene and closely related reactions [175-178], These pericyclic transformations typically proceed in a highly stereoselective fashion and can be exploited for the synthesis of complex natural products possessing decalin skeletons, such as the abietane diterpene wiedamannic... 

Tricyclic diterpenes-resln acids. Wood resin constituents, e.g. abietane derivatives, have also been implicated in pest resistance (Figure 4). Among the conifer-associated sawflles many prefer to feed... 

These processes are normally enzyme-catalyzed. Purefy ctemical processes are seldom encountered with carbon conq)ounds in nature. The few exceptions include the very act of phenol coupling (by which racemic compounds are obtained), cyclization reactions ofpolyprenyl compoimds (which benefit from the preferred conformation of the reaction partners, suitable for the cyclization, Wendt 2000), and Diels-Alder cycloadditions. The latter have been advocated for the biosynthesis of celastroidine A (= volubilide) from a lupane triterpene and an abietane diterpene in two different plants, Hippocratea celastroides Kunth from Mexico (Jimenez-Estrada 2000) and Hippocratea volubilis Linnaeus (Alvarenga 2000). 

The abietane diterpene carnosic acid (89), a derivative of ferruginol, is found in the popular Labiatae herb, sage and rosemary and is considered a precursor of other diterpenoid constituents in the herb [20,21]. Wenkert et al [22] have established the structure of carnosic acid (89). Carnosic acid (89) and related diterpenes such as camasol (90) and rosemanol (91) Fig. (11) possess powerful antioxidant activities [23] but carnosic acid (89) is the most powerful potency among these diterpenes. Carnosic acid (89)... 

Fig (11) Camosic acid (89) is an abietane diterpene and has been isolated from the leaves of sage as pale-yellow powder, m.p. 194.5 - 195°C (crystallized from acetic acid). Its oxidation products have been identified as (92), an orange powder, m.p. 129°C and (93), a yellow powder, m.p. 172 - 173°C. 

Camosol (abietane diterpene) Rosmarinus officinalis. Salvia officinalis (Lamiaceae) HIV-1 protease (> 30 pM) [54]... 

Yokoyama, R., Huang, J.M., Hosoda, A., Kino, K., Yang, C.S. and Fukuyama, Y. (2003) Seco-prezizaane-type sesquiterpenes and an abietane-type diterpene from lllicium minwanense. Journal of Natural Products... 

The first Mexican substance searched for, found, and isolated based on old traditions, was the sesquiterpene hemandulcin from Lippia dulcis Trev. It was determined by a human taste panel to be more than 1000 times sweeter than sucrose. The structure of this sesquiterpene was determined and confirmed by chemical synthesis. It was nontoxic when administered orally to mice, and did not induce bacterial mutation.5 Further work has been carried out with some of the plants more frequently used (Table 12.3). The sesquiterpene alkaloids hippocrateine I, hippocrateine II, and emarginatine were identified in Hippocratea excelsa used in Mexican traditional medicine, and antimicrobial abietane type diterpenes were isolated from Salvia albocaerulea.6 7... 

PEREDA-MIRANDA, R., HERNANDEZ, L., LOPEZ, R A novel antimicrobial abietane-type diterpene from Salvia albocaerulea., Planta Med., 1992,58,223-224. 

From the hairy roots of Salvia broussonetia (Lamiaceae), 14-deoxycoleon U (198) and demethylsalvicanol (199) were isolated together with other diterpenes. Of all the diterpenes isolated, 14-deoxycoleon U was a strong antifeedant against L. decemlineata,12 whereas 199 exhibited only moderate activity. Several compounds similar to 198 were not active, suggesting a possible role for the unsaturation of ring B, a feature missing in 6a-hydroxydemethylcryptojaponol (200), which was not active. None of the isolated abietanes exhibited any antifeedant activity against S. littoralis. 

Abietane diterpenes (C61C61C6 with varying degrees of unsaturation) include the 5-LOX inhibitor abietane, the GABA(A) receptor antagonist taxodione and the bitter tastant carnosol. 

Hydroxyierruginol (abietane diterpene) Salacia obbnga (Celastraceae) [root] AR (rat lens) (> 100)... 

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