Abietane

Last updated
Abietane
Abietane.svg
Names
IUPAC name
Abietane
Systematic IUPAC name
(4aR,4bS,7S,8aS,10aS)-1,1,4a-Trimethyl-7-(propan-2-yl)tetradecahydrophenanthrene
Other names
13α-Isopropylpodocarpane
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
PubChem CID
  • InChI=1S/C20H36/c1-14(2)15-7-9-17-16(13-15)8-10-18-19(3,4)11-6-12-20(17,18)5/h14-18H,6-13H2,1-5H3/t15-,16-,17-,18-,20+/m0/s1 Yes check.svgY
    Key: STIVVCHBLMGYSL-ZYNAIFEFSA-N Yes check.svgY
  • [H][C@]12[C@@](C[C@@H](C(C)C)CC2)([H])CC[C@@]3([H])C(C)(C)CCC[C@@]31C
Properties
C20H36
Molar mass 276.508 g·mol−1
Appearancecolorless
Density 0.876 g/ml
Boiling point 338
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

Abietane is an organic compound with the formula C20H36. It is a tricyclic, saturated hydrocarbon with an elaborate stereochemistry. [1] [2] It is a colorless solid. It is of little biochemical interest except as a reference structure of the abietanes,

Contents

Abietane skeleton numbering scheme Abietane Numbering.svg
Abietane skeleton numbering scheme

Abietanes

Abietanes are a large family of diterpenoids. Individual members of these diterpenoids are also colorless hydrophobic organic compounds. They are usually encountered as mixtures. Most prominent of the abietanes is abietic acid, the major constituent of rosin. Other abietanes are carnosic acid and ferruginol. Some abietanes are of interest in biogeochemistry as markers indicating the source organisms. Abietanes are tricyclic 20-carbon diterpenoids characterized by three fused six-membered rings and alkyl groups at carbons 4, 10, and 13. In higher plants, abietanes and other diterpenoids are synthesized from four five-carbon isoprene units. Abietanes are generally nonpolar, volatile, and less dense than water. The presence of one or more polar functional groups (typically a carboxylic acid or alcohol) tends to increase the polarity and boiling point of a given abietane relative to its unsubstituted hydrocarbon form.

Biological sources and synthesis

Proposed diagenetic pathway for abietic acid involving defunctionalization and aromatization to form retene Abietic Acid Diagenesis horizontal.svg
Proposed diagenetic pathway for abietic acid involving defunctionalization and aromatization to form retene
Abietanes found in the rock record are typically interpreted as evidence of higher plants, particularly gymnosperms, in the deep past. Abietane Diagenesis Scheme.svg
Abietanes found in the rock record are typically interpreted as evidence of higher plants, particularly gymnosperms, in the deep past.

The abietanes are derived, biologically or geologically from abietic acid and related resin acids.

Diagenetic transformation of biomolecules is not fully understood, but several broad diagenetic patterns are hypothesized to affect the transformation of abietanes as they are heated and pressurized in sediments. The first of these patterns is defunctionalization. In particular, the reducing conditions of diagenesis are believed to cause abietanes to lose oxygen-containing functional groups, including carboxylic acids and alcohols, as well as methyl groups. [3] In addition to defunctionalization, abietanes likely undergo dehydrogenation and aromatization reactions to form more energetically stable systems of conjugated pi bonds in their characteristic three ring structure. The hypothesized diagenetic pathway of abietic acid is illustrative of these general patterns. Abietic acid is dehydrogenated to dehydroabietic acid, which then loses its carboxylic acid functional group to become dehydroabietin. Loss of the 5-Me group and further dehydrogenation form the aromatic 1,2,3,4-tetrahydroretene molecule. Final aromatization produces retene, a common biomarker molecule observed in sedimentary samples. [3]

Analysis

Abietanes found in modern gymnosperm resins as well as in the rock record are separated and characterized by gas chromatography-mass spectrometry (GC-MS). Because polar functional groups reduce molecular volatility and make separation by gas chromatography difficult, abietane derivatives containing carboxylic acid and alcohol moieties are often derivatized with trimethylsilyl groups by treatment with BSTFA prior to GC-MS analysis. [4] More oxidized abietane derivatives have been studied using thermally assisted methylation using tetramethylammonium hydroxide (TMAH) followed by GC-MS analysis. [5] MS-MS analysis has been used to elucidate fragmentation mechanisms for mass spectrum peaks of interest. [4] Mass spectra for abietic acid and some other common abietanes are publicly available in the NIST database. [6] The spectrum for abietic acid possesses characteristic peaks at m/z = 256 and 241. [4]

Biogeochemistry of abietanes

Abietanes are found in the tissues and resins of certain higher plants, particularly gymnosperms. [7] [8] Although the functions of terpenes are not fully understood, conifers appear to produce abietane diterpenoids as a form of defense against insect and microbial attack. [9] [10] Some abietane diterpenoids, especially aromatic abietenes, are of interest to the pharmacology and natural products communities for their potential biological activities. [1] In the rock record, abietanes are commonly found in amber as well as in fossil wood, sometimes in the form of the mineral fichtelite. Additionally, abietanes are observed in sediments—both riverine and marine—and in coals, where they are often interpreted as geochemical biomarkers for terrestrial input from conifers. [7] [11] [9] [3] [12]

Use as a biomarker

Abietanes preserved in geological settings are typically interpreted to derive from gymnosperms, specifically conifers. [12] [3] [9] Although both modern angiosperms and modern gymnosperms synthesize terpenoids, gymnosperm tissues tend to contain significantly higher terpenoid concentrations than angiosperm tissues. [8] Additionally, the relative abundances of di-, tri-, and penta-cyclic terpenoids varies between gymnosperms and angiosperms. Although some angiosperm families (notably Burseraceae, Euphorbiaceae and Ranunculaceae) are also known to produce abietanes, in general, tricyclic diterpenoids, including abietanes, are much more abundant in gymnosperms. [8] [7] For these reasons, and because conifers produce significant biomass relative to other gymnosperms, abietanes preserved in geological settings are typically interpreted as conifer biomarkers. It is important to note, however, that such interpretations rely on the assumption that terpenoid distributions and abundances in ancient plants were similar to those in modern plants. Loss of more volatile mono- and sesquiterpenoids during diagenetic heating may help explain the different relative abundance of diterpenoids, including abietanes, in ancient resins and the rock record compared to modern conifer samples. [12]

Examples from archaeology

  • Abietenes from colophony, tar, and pitch have been identified in caulking used on ancient ships. [12]
  • Abietanes have been used to identify conifer resins associated with Egyptian mummies. [12]
  • The ratio of oxidation products of abietanes including dehydroabietic acid and de-7-oxo-dehydroabietic acid and 15-hydroxyl-7-oxo-dehydroabietic acid have been used to estimate the oxidation state of varnish on Vermeer's famous painting, "Girl with a Pearl Earring." [5]

Examples from geochemistry

  • Carbon isotopic measurements of abietanes and other di- and tri-terpenoids have been made in modern plants, as well as in ancient samples, where they reveal a carbon isotope excursion during the Paleocene-Eocene Thermal Maximum (PETM). [8] [13]
  • Abietanes found in marine sediments have been used as evidence of ancient terrigenous input. [14]
  • Abietane diterpenoids have been attributed to resinous vascular plants in samples dating to the Jurassic. [11]

See also

Related Research Articles

<span class="mw-page-title-main">Abietic acid</span> Chemical compound

Abietic acid is a diterpenoid found in coniferous trees. It is supposed to exist as a defend the host plant from insect attack or various wounds. Chemically, it is a complicated molecule featuring two alkene groups and a carboxylic acid within a chiral tricyclic framework. As the major component of rosin, it is a commercially important. Historically speaking, it was a major component of naval stores. It is the most common of the resin acids. Another common resin acid is pimaric acid, which converts to abietic acid upon heating.

Organic geochemistry is the study of the impacts and processes that organisms have had on the Earth. It is mainly concerned with the composition and mode of origin of organic matter in rocks and in bodies of water. The study of organic geochemistry is traced to the work of Alfred E. Treibs, "the father of organic geochemistry." Treibs first isolated metalloporphyrins from petroleum. This discovery established the biological origin of petroleum, which was previously poorly understood. Metalloporphyrins in general are highly stable organic compounds, and the detailed structures of the extracted derivatives made clear that they originated from chlorophyll.

Resin acid refers to any of several related carboxylic acids found in tree resins. Nearly all resin acids have the same basic skeleton: three fused rings having the empirical formula C19H29COOH. Resin acids occur in nature as tacky, yellowish gums consisting of several compounds. They are water-insoluble. A common resin acid is abietic acid. Resin acids are used to produce soaps for diverse applications, but their use is being displaced increasingly by synthetic acids such as 2-ethylhexanoic acid or petroleum-derived naphthenic acids.

<span class="mw-page-title-main">Paleolimnology</span> Scientific study of ancient lakes and streams

Paleolimnology is a scientific sub-discipline closely related to both limnology and paleoecology. Paleolimnological studies focus on reconstructing the past environments of inland waters using the geologic record, especially with regard to events such as climatic change, eutrophication, acidification, and internal ontogenic processes.

<span class="mw-page-title-main">Cholestane</span> Chemical compound

Cholestane is a saturated tetracyclic triterpene. This 27-carbon biomarker is produced by diagenesis of cholesterol and is one of the most abundant biomarkers in the rock record. Presence of cholestane, its derivatives and related chemical compounds in environmental samples is commonly interpreted as an indicator of animal life and/or traces of O2, as animals are known for exclusively producing cholesterol, and thus has been used to draw evolutionary relationships between ancient organisms of unknown phylogenetic origin and modern metazoan taxa. Cholesterol is made in low abundance by other organisms (e.g., rhodophytes, land plants), but because these other organisms produce a variety of sterols it cannot be used as a conclusive indicator of any one taxon. It is often found in analysis of organic compounds in petroleum.

Phytane is the isoprenoid alkane formed when phytol, a chemical substituent of chlorophyll, loses its hydroxyl group. When phytol loses one carbon atom, it yields pristane. Other sources of phytane and pristane have also been proposed than phytol.

<span class="mw-page-title-main">Ferruginol</span> Chemical compound

Ferruginol is a natural phenol with a terpenoid substructure. Specifically, it is a diterpene of the abietane chemical class, meaning it is characterized by three fused six-membered rings and alkyl functional groups. Ferruginol was first identified in 1939 by Brandt and Neubauer as the main component in the resin of the Miro tree and has since been isolated from other conifer species in the families Cupressaceae and Podocarpaceae. As a biomarker, the presence of ferruginol in fossils, mainly resin, is used to describe the density of these conifers in that particular biosphere throughout time.

<span class="mw-page-title-main">Taxodone</span> Chemical compound

Taxodone is a naturally occurring diterpenoid found in Taxodium distichum, Rosmarinus officinalis (rosemary), several salvia species and other plants, along with its oxidized rearrangement product, taxodione. Taxodone and taxodione exhibit anticancer, antibacterial, antioxidant, antifungal, insecticide, and antifeedant activities.

<span class="mw-page-title-main">Levopimaric acid</span> Chemical compound

Levopimaric acid is an abietane-type of diterpene resin acid. It is a major constituent of pine oleoresin with the chemical formula of C20H30O2. In general, the abietene types of diterpene resin acid have various biological activities, such as antibacterial, cardiovascular and antioxidant. Levopimaric acid accounts for about 18 to 25% of pine oleoresin. The production of oleoresin by conifer species is an important component of the defense response against insect attack and fungal pathogen infection.

<span class="mw-page-title-main">Dinosterol</span> Chemical compound

Dinosterol (4α,23,24-trimethyl-5α-cholest-22E-en-3β-ol) is a 4α-methyl sterol that is produced by several genera of dinoflagellates and is rarely found in other classes of protists. The steroidal alkane, dinosterane, is the 'molecular fossil' of dinosterol, meaning that dinosterane has the same carbon skeleton as dinosterol, but lacks dinosterol's hydroxyl group and olefin functionality. As such, dinosterane is often used as a biomarker to identify the presence of dinoflagellates in sediments.

Crocetane, or 2,6,11,15-tetramethylhexadecane, is an isoprenoid hydrocarbon compound. Unlike its isomer phytane, crocetane has a tail-to-tail linked isoprenoid skeleton. Crocetane has been detected in modern sediments and geological records as a biomarker, often associated with anaerobic methane oxidation.

<span class="mw-page-title-main">24-Norcholestane</span> Chemical compound

24-Norcholestane, a steroid derivative, is used as a biomarker to constrain the source age of sediments and petroleum through the ratio between 24-norcholestane and 27-norcholestane, especially when used with other age diagnostic biomarkers, like oleanane. While the origins of this compound are still unknown, it is thought that they are derived from diatoms due to their identification in diatom rich sediments and environments. In addition, it was found that 24-norcholestane levels increased in correlation with diatom evolution. Another possible source of 24-norcholestane is from dinoflagellates, albeit to a much lower extent.

<span class="mw-page-title-main">Sugiol</span> Chemical compound

Sugiol is a phenolic abietane derivative of ferruginol and can be used as a biomarker for specific families of conifers. The presence of sugiol can be used to identify the Cupressaceae s.1., podocarpaceae, and Araucaraiaceae families of conifers. The polar terpenoids are among the most resistant molecules to degradation besides n-alkanes and fatty acids, affording them high viability as biomarkers due to their longevity in the sedimentary record. Significant amounts of sugiol has been detected in fossil wood dated to the Eocene and Miocene periods, as well as a sample of Protopodocarpoxylon dated to the middle Jurassic.

Arborane is a class of pentacyclic triterpene consisting of organic compounds with four 6-membered rings and one 5-membered ring. Arboranes are thought to be derived from arborinols, a class of natural cyclic triterpenoids typically produced by flowering plants. Thus arboranes are used as a biomarker for angiosperms and cordaites. Arborane is a stereoisomer of a compound called fernane, the diagenetic product of fernene and fernenol. Because aborinol and fernenol have different biological sources, the ratio of arborane/fernane in a sample can be used to reconstruct a record for the relative abundances of different plants.

<span class="mw-page-title-main">Lycopane</span> Chemical compound

Lycopane (C40H82; 2,6,10,14,19,23,27,31-octamethyldotriacontane), a 40 carbon alkane isoprenoid, is a widely present biomarker that is often found in anoxic settings. It has been identified in anoxically deposited lacustrine sediments (such as the Messel formation and the Condor oil shale deposit). It has been found in sulfidic and anoxic hypersaline environments (such as the Sdom Formation). It has been widely identified in modern marine sediments, including the Peru upwelling zone, the Black Sea, and the Cariaco Trench. It has been found only rarely in crude oils.

<span class="mw-page-title-main">Chamaecydin</span> Chemical compound

Chamaecydin is a chemical compound with the molecular formula C30H40O3. It is made up of three six-membered rings and two five-membered rings and has one polar hydroxyl functional group. It is well preserved in the rock record and is only found in a specific family of conifers, the swamp cypress subfamily. The presence and abundance of chamaecydin in the rock record can reveal environmental changes in ancient biomes.

<span class="mw-page-title-main">Hydroxyarchaeol</span> Chemical compound

Hydroxyarchaeol is a core lipid unique to archaea, similar to archaeol, with a hydroxide functional group at the carbon-3 position of one of its ether side chains. It is found exclusively in certain taxa of methanogenic archaea, and is a common biomarker for methanogenesis and methane-oxidation. Isotopic analysis of hydroxyarchaeol can be informative about the environment and substrates for methanogenesis.

Carotane is a plant pigment that belongs to a class of tetraterpenes called carotenoids. These tetraterpenes are known for their yellow, orange, and red colors as these are organic pigments. These colors are beneficial to their host species that tend to be plants and algae. Within plants, carotenoids play the major roles of allowing light to be absorbed via photosynthesis as well ad providing photoprotection through a non-photochemical quenching.

Biphytane (or bisphytane) is a C40 isoprenoid produced from glycerol dialkyl glycerol tetraether (GDGT) degradation. As a common lipid membrane component, biphytane is widely used as a biomarker for archaea. In particular, given its association with sites of active anaerobic oxidation of methane (AOM), it is considered a biomarker of methanotrophic archaea. It has been found in both marine and terrestrial environments.

<span class="mw-page-title-main">Palustric acid</span> Chemical compound

Palustric acid is an organic compound with the formula C20H30O2. It is classified as a diterpenoid and a resin acid. Palustric acid is an isomer of abietic acid: the location of the two C=C bonds differ in these two compounds. It is a colorless solid that is soluble in polar organic solvents. In terms of biological function palustric acid protects its host trees, especially conifers, against insects, an example of plant defense against herbivory. It is biosynthesized from the C20 precursor geranylgeranyl diphosphate.

References

  1. 1 2 3 González, Miguel A. (2015). "Aromatic abietane diterpenoids: their biological activity and synthesis". Natural Product Reports. 32 (5): 684–704. doi:10.1039/C4NP00110A. ISSN   0265-0568. PMID   25643290.
  2. ↑ Peters, Reuben J. (2010). "Two rings in them all: The labdane-related diterpenoids". Natural Product Reports. 27 (11): 1521–1530. doi:10.1039/c0np00019a. ISSN   0265-0568. PMC   3766046 . PMID   20890488.
  3. 1 2 3 4 5 Killops, S. D. (1993). An introduction to organic geochemistry. V. J. Killops. Harlow, Essex, England: Longman Scientific & Technical. ISBN   0-582-08040-1. OCLC   27895324.
  4. 1 2 3 Azemard, Clara; Menager, Matthieu; Vieillescazes, Catherine (2016-09-01). "Analysis of diterpenic compounds by GC-MS/MS: contribution to the identification of main conifer resins". Analytical and Bioanalytical Chemistry. 408 (24): 6599–6612. doi:10.1007/s00216-016-9772-9. ISSN   1618-2650. PMID   27449645. S2CID   8264935.
  5. 1 2 Pastorova, I.; Van Der Berg, K.J; Boon, J.J; Verhoeven, J.W (1997-08-01). "Analysis of oxidised diterpenoid acids using thermally assisted methylation with TMAH". Journal of Analytical and Applied Pyrolysis. 43 (1): 41–57. doi:10.1016/S0165-2370(97)00058-2. ISSN   0165-2370.
  6. ↑ "Abietic acid". webbook.nist.gov. Retrieved 2021-05-22.
  7. 1 2 3 Otto, A.; Walther, H.; Püttmann, W. (January 1997). "Sesqui- and diterpenoid biomarkers preserved in Taxodium-rich Oligocene oxbow lake clays, Weisselster basin, Germany". Organic Geochemistry. 26 (1–2): 105–115. Bibcode:1997OrGeo..26..105O. doi:10.1016/s0146-6380(96)00133-7. ISSN   0146-6380.
  8. 1 2 3 4 Diefendorf, Aaron F.; Freeman, Katherine H.; Wing, Scott L. (2012-05-15). "Distribution and carbon isotope patterns of diterpenoids and triterpenoids in modern temperate C3 trees and their geochemical significance". Geochimica et Cosmochimica Acta. 85: 342–356. Bibcode:2012GeCoA..85..342D. doi:10.1016/j.gca.2012.02.016. ISSN   0016-7037.
  9. 1 2 3 Freeman, K.H.; Pancost, R.D. (2014), "Biomarkers for Terrestrial Plants and Climate", Treatise on Geochemistry, Elsevier, pp. 395–416, doi:10.1016/b978-0-08-095975-7.01028-7, ISBN   978-0-08-098300-4 , retrieved 2021-05-10
  10. ↑ Mason, Charles J.; Klepzig, Kier D.; Kopper, Brian J.; Kersten, Philip J.; Illman, Barbara L.; Raffa, Kenneth F. (June 2015). "Contrasting Patterns of Diterpene Acid Induction by Red Pine and White Spruce to Simulated Bark Beetle Attack, and Interspecific Differences in Sensitivity Among Fungal Associates". Journal of Chemical Ecology. 41 (6): 524–532. Bibcode:2015JCEco..41..524M. doi:10.1007/s10886-015-0588-4. ISSN   0098-0331. PMID   26003180. S2CID   1506353.
  11. 1 2 Simoneit, Bernd R.T.; Grimalt, J.O.; Wang, T.G.; Cox, R.E.; Hatcher, P.G.; Nissenbaum, A. (January 1986). "Cyclic terpenoids of contemporary resinous plant detritus and of fossil woods, ambers and coals". Organic Geochemistry. 10 (4–6): 877–889. Bibcode:1986OrGeo..10..877S. doi:10.1016/s0146-6380(86)80025-0. ISSN   0146-6380.
  12. 1 2 3 4 5 "Source- and age-related biomarker parameters", The Biomarker Guide, Cambridge University Press, pp. 483–607, 2004-12-16, doi:10.1017/cbo9781107326040.004, ISBN   978-0-521-83762-0 , retrieved 2021-05-10
  13. ↑ Schouten, Stefan; Woltering, Martijn; Rijpstra, W. Irene C.; Sluijs, Appy; Brinkhuis, Henk; Sinninghe Damsté, Jaap S. (June 2007). "The Paleocene–Eocene carbon isotope excursion in higher plant organic matter: Differential fractionation of angiosperms and conifers in the Arctic". Earth and Planetary Science Letters. 258 (3–4): 581–592. Bibcode:2007E&PSL.258..581S. doi:10.1016/j.epsl.2007.04.024. hdl: 1874/385783 . ISSN   0012-821X. S2CID   129625887.
  14. ↑ Simoneit, Bernd R.T (April 1977). "Diterpenoid compounds and other lipids in deep-sea sediments and their geochemical significance". Geochimica et Cosmochimica Acta. 41 (4): 463–476. Bibcode:1977GeCoA..41..463S. doi:10.1016/0016-7037(77)90285-x. ISSN   0016-7037.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.