Germacrene

Germacrenes are a class of volatile organic hydrocarbons, specifically, sesquiterpenes. Germacrenes are typically produced in a number of plant species for their antimicrobial and insecticidal properties, though they also play a role as insect pheromones. Two prominent molecules are germacrene A and germacrene D.

Germacrene A

Names
IUPAC name (1E,5E,8S)-1,5-dimethyl-8-(prop-1-en-2-yl)cyclodeca-1,5-diene
Other names (−)-Germacrene A (E,E)-Germacra-3,9,11-triene (1E,5E,8S)-1,5-dimethyl-8-(1-methylethenyl)-1,5-cyclodecadiene (S-(E,E))-1,5-dimethyl-8-(1-methylethenyl)-1,5-cyclodecadiene
Identifiers
CAS Number	28387-44-2 Y B: 15423-57-1 C: 34323-15-4 D: 37839-63-7
3D model (JSmol)	Interactive image A: Interactive image B: Interactive image C: Interactive image E: Interactive image
Beilstein Reference	6500908 (A) 1864177 (D)
ChEBI	A: CHEBI:36517 B: CHEBI:5337 C: CHEBI:61478 D: CHEBI:49045
ChEMBL	B: ChEMBL448125
ChemSpider	29776407 N A: 7827628 B: 4444852 D: 28288426
KEGG	A: C16141 B: C09672 C: C19747
PubChem CID	A: 9548705 B: 5281519 C: 25244915 D: 5373727 E: 10632030
InChI InChI=1S/C15H26/c1-12(2)15-10-8-13(3)6-5-7-14(4)9-11-15/h6,9,12,15H,5,7-8,10-11H2,1-4H3/b13-6 ,14-9 /t15-/m0/s1 N Key: YDLBHMSVYMFOMI-SDFJSLCBSA-N N InChI=1/C15H26/c1-12(2)15-10-8-13(3)6-5-7-14(4)9-11-15/h6,9,12,15H,5,7-8,10-11H2,1-4H3/b13-6 ,14-9 /t15-/m0/s1 Key: YDLBHMSVYMFOMI-SDFJSLCBBV A: InChI=1S/C15H24/c1-12(2)15-10-8-13(3)6-5-7-14(4)9-11-15/h6,9,15H,1,5,7-8,10-11H2,2-4H3/b13-6 ,14-9 /t15-/m1/s1 Key: XMRKUJJDDKYUHV-DFSVIBJJSA-N D: InChI=1S/C15H24/c1-12(2)15-10-8-13(3)6-5-7-14(4)9-11-15/h7-8,10,12,15H,3,5-6,9,11H2,1-2,4H3/b10-8-,14-7- Key: GAIBLDCXCZKKJE-BZXLUOIMSA-N E: InChI=1S/C15H24/c1-12(2)15-10-8-13(3)6-5-7-14(4)9-11-15/h6,9,11,14-15H,1,5,7-8,10H2,2-4H3/b11-9 ,13-6 Key: OAOGSSAAVUPEKA-BMCYRRRCSA-N
SMILES C/C/1=C\CC/C(=C/C[C@H](CC1)C(C)C)/C A: C/C/1=C\CC/C(=C/C[C@@H](CC1)C(=C)C)/C B: C/C/1=C\CC/C(=C/CC(=C(C)C)CC1)/C C: C/C/1=C\CC/C(=C/C=C(\CC1)/C(C)C)/C E: CC\1CC/C=C(/CCC(/C=C1)C(=C)C)\C
Properties
Chemical formula	C15H24
Molar mass	204.35 g/mol
Density	0.793 g/mL
Boiling point	236.4 °C (457.5 °F; 509.5 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Germacrene D

Names
IUPAC name (S,1Z,6Z)-8-isopropyl-1-methyl-5-methylidenecyclodeca-1,6-diene
Other names 1-methyl-5-methylene-8-(1-methylethyl)-1,6-cyclodecadiene
Identifiers
CAS Number	37839-63-7
3D model (JSmol)	Interactive image
ChemSpider	28288426
PubChem CID	5373727
InChI InChI=1S/C15H24/c1-12(2)15-10-8-13(3)6-5-7-14(4)9-11-15/h7-8,10,12,15H,3,5-6,9,11H2,1-2,4H3/b10-8-,14-7-/t15-/m0/s1 Key: GAIBLDCXCZKKJE-ACWLMNNXSA-N InChI=1/C15H24/c1-12(2)15-10-8-13(3)6-5-7-14(4)9-11-15/h7-8,10,12,15H,3,5-6,9,11H2,1-2,4H3/b10-8-,14-7-/t15-/m0/s1 Key: GAIBLDCXCZKKJE-ACWLMNNXBY
SMILES C/C/1=C/CCC(=C)/C=C\[C@@H](CC1)C(C)C
Properties
Chemical formula	C15H24
Molar mass	204.35 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Structures

Germacrene has five isomers.

Germacrene isomers

Germacrene A	Germacrene B	Germacrene C	Germacrene D	Germacrene E

Natural occurrences

The essential oils of red deadnettle (Lamium purpureum) and hedgenettles (genus Stachys) are characterized by their high contents of germacrene D, as is Clausena anisata. It is also a major component of patchouli oil.

Further reading

General

• Adio, A. M. (2009). "Germacrenes A–E and related compounds: thermal, photochemical and acid induced transannular cyclizations". Tetrahedron. 65 (8): 1533–1552. doi:10.1016/j.tet.2008.11.050.

Germacrene A

• Deguerry, F.; Pastore, L.; Wu, S.; Clark, A.; Chappell, J.; Schalk, M. (2006-10-15). "The diverse sesquiterpene profile of patchouli, Pogostemon cablin, is correlated with a limited number of sesquiterpene synthases". Archives of Biochemistry and Biophysics. 454 (2): 123–136. doi:10.1016/j.abb.2006.08.006. PMID 16970904.
• Omura, H.; Honda, K.; Feeny, P. (2006-09-01). "From terpenoids to aliphatic acids: further evidence for late-instar switch in osmeterial defense as a characteristic trait of swallowtail butterflies in the tribe Papilionini". Journal of Chemical Ecology. 32 (9): 1999–2012. Bibcode:2006JCEco..32.1999O. doi:10.1007/s10886-006-9124-x. PMID 16902823. S2CID 25242966.
• Forcat, S.; Allemann, R. K. (2006-07-07). "Stabilisation of transition states prior to and following eudesmane cation in aristolochene synthase". Organic and Biomolecular Chemistry. 4 (13): 2563–2567. doi:10.1039/b604147g. PMID 16791319.
• Bertea, C. M.; Voster, A.; Verstappen, F. W.; Maffei, M.; Beekwilder, J.; Bouwmeester, H. J. (2006-04-15). "Isoprenoid biosynthesis in Artemisia annua: cloning and heterologous expression of a germacrene A synthase from a glandular trichome cDNA library". Archives of Biochemistry and Biophysics. 448 (1–2): 3–12. doi:10.1016/j.abb.2006.02.026. PMID 16579958.
• Lou, Y; Baldwin, I. T. (2006-03-01). "Silencing of a germin-like gene in Nicotiana attenuata improves performance of native herbivores". Plant Physiology. 140 (3): 1126–1136. doi:10.1104/pp.105.073700. PMC 1400569. PMID 16461381.
• Chang, Y.-J.; Jin, J.; Nam, H.-Y.; Kim, S.-U. (2005-03-01). "Point mutation of ( )-germacrene A synthase from Ixeris dentata". Biotechnology Letters. 27 (5): 285–288. doi:10.1007/s10529-005-0681-9. PMID 15834787. S2CID 21959582.

Germacrene D

• Rivero Cruz, B.; Rivero Cruz, I; Rodríguez, J. M.; Cerda García-Rojas, C. M.; Mata, R. (2006-08-01). "Qualitative and quantitative analysis of the active components of the essential oil from 'Brickellia veronicaefolia by nuclear magnetic resonance spectroscopy". Journal of Natural Products. 69 (8): 1172–1176. doi:10.1021/np060180b. PMID 16933870.
• Yang, F.-Q.; Li, S.-P.; Chen, Y.; Lao, S.-C.; Wang, Y.-T.; Dong, T.-T.; Tsim, K.-W. (2005-09-15). "Identification and quantitation of eleven sesquiterpenes in three species of Curcuma rhizomes by pressurized liquid extraction and gas chromatography-mass spectrometry". Journal of Pharmaceutical and Biomedical Analysis. 39 (3–4): 552–558. doi:10.1016/j.jpba.2005.05.001. PMID 18636818.
• Umlauf, D.; Zapp, J.; Becker, H.; Adam, K. P. (2004-09-01). "Biosynthesis of the irregular monoterpene artemisia ketone, the sesquiterpene germacrene D and other isoprenoids in Tanacetum vulgare L. (Asteraceae)". Phytochemistry. 65 (17): 2463–2470. Bibcode:2004PChem..65.2463U. doi:10.1016/j.phytochem.2004.08.019. PMID 15381410.
• Agnihotri, V. K.; Thappa, R. K.; Meena, B.; Kapahi, B. K.; Saxena, R. K.; Qazi, G. N.; Agarwal, S. G. (2004-08-01). "Essential oil composition of aerial parts of Angelica glauca growing wild in North-West Himalaya (India)". Phytochemistry. 65 (16): 2411–2413. Bibcode:2004PChem..65.2411A. doi:10.1016/j.phytochem.2004.07.004. PMID 15381015.
• Raal, A.; Paaver, U.; Arak, E.; Orav, A. (2004). "Content and composition of the essential oil of Thymus serpyllum L. growing wild in Estonia". Medicina (Kaunas). 40 (8): 795–800. PMID 15300002.
• He, X.; Cane, D. E. (2004-03-10). "Mechanism and stereochemistry of the germacradienol/germacrene D synthase of Streptomyces coelicolor A3(2)". Journal of the American Chemical Society. 126 (9): 2678–2679. doi:10.1021/ja039929k. PMID 14995166.
• Arimura, G.-I.; Huber, D. P. W.; Bohlmann, J. (2004). "Forest tent caterpillars (Malacosoma disstria) induce local and systemic diurnal emissions of terpenoid volatiles in hybrid poplar (Populus trichocarpa × deltoides): cDNA cloning, functional characterization, and patterns of gene expression of (−)-germacrene D synthase, PtdTPS1". The Plant Journal. 37 (4): 603–616. doi:10.1111/j.1365-313X.2003.01987.x. PMID 14756770.