Betulin is an abundant, naturally occurring triterpene. It is commonly isolated from the bark of birch trees. It forms up to 30% of the dry weight of silver birch bark.[2] It is also found in birch sap.[citation needed] Inonotus obliquus contains betulin.[3]

Betulin
Betulin
Names
IUPAC name
Lup-20(29)-ene-3β,28-diol
Systematic IUPAC name
(1R,3aS,5aR,5bR,7aR,9S,11aR,11bR,13aR,13bR)-3a-(Hydroxymethyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)icosahydro-1H-cyclopenta[a]chrysen-9-ol
Other names
Betulinol, betuline, betulol, betulinic alcohol, trochol
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
ECHA InfoCard 100.006.797 Edit this at Wikidata
EC Number
  • 207-475-5
KEGG
UNII
  • InChI=1S/C30H50O2/c1-19(2)20-10-15-30(18-31)17-16-28(6)21(25(20)30)8-9-23-27(5)13-12-24(32)26(3,4)22(27)11-14-29(23,28)7/h20-25,31-32H,1,8-18H2,2-7H3/t20-,21+,22-,23+,24-,25+,27-,28+,29+,30+/m0/s1 checkY
    Key: FVWJYYTZTCVBKE-ROUWMTJPSA-N checkY
  • InChI=1/C30H50O2/c1-19(2)20-10-15-30(18-31)17-16-28(6)21(25(20)30)8-9-23-27(5)13-12-24(32)26(3,4)22(27)11-14-29(23,28)7/h20-25,31-32H,1,8-18H2,2-7H3/t20-,21+,22-,23+,24-,25+,27-,28+,29+,30+/m0/s1
    Key: FVWJYYTZTCVBKE-ROUWMTJPBQ
  • O[C@H]5CC[C@@]4([C@@H]3[C@@]([C@]2([C@@H]([C@@H]1[C@](CO)(CC[C@H]1C(=C)C)CC2)CC3)C)(C)CC[C@H]4C5(C)C)C
  • CC(=C)[C@@H]1CC[C@]2([C@H]1[C@H]3CC[C@@H]4[C@]5(CC[C@@H](C([C@@H]5CC[C@]4([C@@]3(CC2)C)C)(C)C)O)C)CO
Properties
C30H50O2
Molar mass 442.728 g·mol−1
Appearance solid with needle-like crystals[1]
Melting point 256 to 257 °C (493 to 495 °F; 529 to 530 K)
insoluble[1]
Solubility slightly soluble in ethanol and benzene; soluble in diethyl ether, ethyl acetate and ligroin[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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The compound in the bark gives the tree its white color which appears to protect the tree from mid-winter overheating by the sun. As a result, birches are some of the northernmost occurring deciduous trees.

History

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Betulin was discovered in 1788 by German-Russian chemist Johann Tobias Lowitz.[4][5]

Chemistry

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Chemically, betulin is a triterpenoid of lupane structure. It has a pentacyclic ring structure, and hydroxyl groups in positions C3 and C28.

See also

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References

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  1. ^ a b c Haynes, William M.; Lide, David R.; Bruno, Thomas J. (2014). "3". CRC Handbook of Chemistry and Physics (95th ed.). Boca Raton, Florida: CRC Press. p. 340. ISBN 9781482208689. OCLC 908078665.
  2. ^ Green, Brian; Bentley, Michael D.; Chung, Bong Y.; Lynch, Nicholas G.; Jensen, Bruce L. (2007-12-01). "Isolation of Betulin and Rearrangement to Allobetulin. A Biomimetic Natural Product Synthesis". Journal of Chemical Education. 84 (12): 1985. Bibcode:2007JChEd..84.1985G. doi:10.1021/ed084p1985.
  3. ^ Gao, Yuan; Xu, Hongyu; Lu, Zhenming; Xu, Zhenghong (November 2009). "Quantitative determination of steroids in the fruiting bodies and submerged-cultured mycelia of Inonotus obliquus". Se Pu. 27 (6): 745–749. ISSN 1000-8713. PMID 20352924.
  4. ^ Lowitz, J. T. (1788). "Űber eine neue, fast benzoeartige substanz der briken". Crell's Chem. Ann. 1: 312–317.
  5. ^ Król, Sylwia Katarzyna; Kiełbus, Michał; Rivero-Müller, Adolfo; Stepulak, Andrzej (2015). "Comprehensive Review on Betulin as a Potent Anticancer Agent". BioMed Research International. 2015: 584189. doi:10.1155/2015/584189. PMC 4383233. PMID 25866796.