Abietane

Source Juniperus thurifera Mol. formula 20 2002 Mol. wt. 300 Solvent CDC1  

Ohmoto, M.Saito and K. Yamaguchi, Chem. Pharm. Bull. (Tokyo), 35(6), 2443 (1987). 

Source Salvia hypargeia Fisch. et Mey. Mol. formula 20 20 3 Mol. wt. 314 Solvent CDC1  

Source Euphorbia pallasii Turcz (syn. E. fisheriana Stendel) 

Source Cedms deodara Loud. Mol. formula CgQHggOg Mol. wt. 316 Solvent CDC1  

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With very few exceptions, the pine resin acids belong to four basic skeletal classes abietane, pimarane, isopimarane, and labdane (Fig. 7). The acids of the abietane, pimarane and isopimarane series have a isopropyl or methyl/ethyl group in the carbon-13 position and a single carboxyl group in the carbon-18 position, and differ only in the number and location of the carbon-carbon double bonds (the most common have two carbon-carbon double bonds). The acids of labdane series are less common and contain one carboxyl group in the carbon-19 position. 

The structures and nomenclature for the common pine resin acids based on the abietane skeleton (abietic-type acids) are given in Fig. 8. The abietic, neoabietic, palustric and levopimaric acids differ only in tbe location of tbeir two double bonds. All double bonds are endocyclic, except in the neoabietic acid in which one is exocyclic. 

Fig. 8. Common acids of the abietane skeletal class (abietic-iype acids) (see p. 268 in [18]).

N-Methyl-anilin4 I-Methylamino-naphthalin4 3ft-Hydroxy-6-methyl-6-aza-cholestan5 l -Methylamino-dehydro-abietan-Hydrochlorid1 2,3-Bis- methylamino]-pleiadan ... 

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. 

Liu, H.-J. and Wu, C.-L. 1997. A rearranged abietane-type diterpenoid from the liverwort Makinoa crispata. Phytochemistry 44 1523-1525. 

Smith DJ, VJJ Martin, WH Mohn (2004) A cytochrome P450 involved in the metabolism of abietane diterpenoids by Pseudomonas abietaniphila BMKE-9. J Bacterial 186 3631-3639. 

Martin VJJ, WW Mohn (2000) Genetic investigation of the catabolic pathway for degradation of abietane diterpenoids by Pseudomonas abietaniphila BKME-9. J Bacteriol 182 3784-3793. 

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. 

Esquivel, B. Flores, M. Hemandez-Ortega, S. Toscano, R. A. Ramamoorthy, T. P. Abietane and icetexane diterpenoids from the roots of Salvia aspera. Phytochemistry 1995, 39, 139-143. 

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. 

Guerrero, I. C. Andres, L. S. Leon, L. G. Machin, R. P. Padron, J. M. Luis, J. G. Delgadillo, J. Abietane diterpenoids from Salvia pachyphylla and S. clevelandii with cytotoxic activity against human cancer cell lines. J. Nat. Prod. 2006, 69, 1803-1805. 

Esquivel, B. Sanchez, A. A. Vergara, F. Matus, W. Hemandez-Ortega, S. Ramtrez-Apan, M. T. Abietane diterpenoids from the roots of some Mexican Salvia species... 

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. 

Hueso-Rodriguez, J. A. Jimeno, M. L. Rodriguez, B. Savona, G. Bruno, M. Abietane diterpenoids from roots of Salvia phlomoides. Phytochemistry 1983, 22, 2005-2009. 

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. 

Hernandez M, Esquive Bl, Cardenas J, Rodriguez-Hahn L, Ramamoorthy TP. Diterpenoid abietane quinones isolated from Salvia regia. Phytochemistry 1987 26 3297-3299. 

The same authors also used this approach for an enantioselective synthesis of the natural product (-i-)-royleanone (4-54), a member of the abietane diterpenoid family [17]. The enantiopure sulfoxide 4-50 was oxidized using DDQ to give crude 1,4-ben-zoquinone 4-51, which by reaction with the diene 4-52 in CH2C12 under high pressure led to the tricyclic compound 4-53 with 97 % ee and 60% yield based on 4-50 (Scheme 4.11). Hydrogenation of the unconjugated double bond in 4-53 afforded 35% of the desired compound 4-54 after crystallization to separate it from the unwanted cis-isomer. 

In 2011, Hartwig and coworkers reported the total synthesis of taiwaniaquinol B (55, Scheme 11.9), a member of a family of diterpenoids that are derived from the abietane skeleton [36]. A key aspect of the Hartwig synthesis of taiwaniaquinol B was the use of the iridium-catalyzed borylation reaction to accomplish the C(5) functionalization of resorcinol derivative 53. This regioselectivity for the overall bromination is complementary to that which would be obtained using a standard electrophilic aromatic substitution (EAS) reaction. In the transformation of 53 to 54, a sterically controlled borylation was first accomplished, which was then followed by treatment of the boronic ester intermediate with cupric bromide to... 

However, in many archaeological samples pimarane diterpenoids are often absent, and of the abietane compounds only dehydroabietic acid remains. In fact, dehydroabietic acid is present as a minor component in the fresh resins, but its abundance increases on ageing at the expense of the abietadienic acids since the latter undergo oxidative dehydrogenation to the more stable aromatic triene, dehydroabietic acid [2,18]. If oxygen is available, dehydroabietic acid can be oxidized to 7-oxodehydroabietic acid and 15-hydroxy-7-oxodehydroabietic acid. Since these diterpenoid compounds are often the dominant components in archaeological samples [95,97], they are considered characteristic for the presence of Pinaceae resins. 

Figure 3.17 shows the mass profile of the resinous material collected from the Roman amphora. It shows the presence of abietane skeleton diterpenoids due to the occurrence of the peaks at m/z 315, 299, 285, 253 and 239. Furthermore, a high degree of oxidation of the resin was ascertained by the abundance of peaks at m/z 315 and 253, deriving from 7-oxo-dehydroabietic acid, and those at m/z 331 and 329, from highly oxidised tricyclic diterpenoid molecules. Finally, the presence of retene was evidenced by the peaks at m/z 234 and 219. The results showed that a pitch from Pinaceae had been in the amphora. 

These two examples demonstrate clearly the usefulness of SPME to detect volatile compounds in complex mixtures. Among the few sesquiterpenes identified in the SPME extract for the two samples, longifolene can be considered as a biomarker of a substance originating from a conifer tree. The absence of abietane or pimarane diterpenoids is indicative of the use of parts of the tree with low resin content. 

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... 

Terpenoids are susceptible to a number of alterations mediated by oxidation and reduction reactions. For example, the most abundant molecule in aged Pinus samples is dehydroabietic acid [Structure 7.10], a monoaromatic diterpenoid based on the abietane skeleton which occurs in fresh (bleed) resins only as a minor component. This molecule forms during the oxidative dehydrogenation of abietic acid, which predominates in rosins. Further atmospheric oxidation (autoxidation) leads to 7-oxodehydroabietic acid [Structure 7.11]. This molecule has been identified in many aged coniferous resins such as those used to line transport vessels in the Roman period (Heron and Pollard, 1988 Beck et al., 1989), in thinly spread resins used in paint media (Mills and White, 1994 172-174) and as a component of resin recovered from Egyptian mummy wrappings (Proefke and Rinehart, 1992). 

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