Pristan
| Structural formula | |||||||||||||||||||
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| Simplified structural formula without specifying the stereochemistry | |||||||||||||||||||
| General | |||||||||||||||||||
| Surname | Pristan | ||||||||||||||||||
| other names | |||||||||||||||||||
| Molecular formula | C 19 H 40 | ||||||||||||||||||
| Brief description |
colorless liquid |
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| properties | |||||||||||||||||||
| Molar mass | 268.51 g mol −1 | ||||||||||||||||||
| Physical state |
liquid |
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| density |
0.78 g ml −1 |
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| Melting point |
−100 ° C |
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| boiling point |
296 ° C |
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| solubility |
soluble in many organic solvents |
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| Refractive index |
1.4370 (20 ° C) |
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| As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C | |||||||||||||||||||
Pristan (systematic name: 2,6,10,14-tetramethylpentadecane) is a naturally occurring chemical compound , a colorless oil. It is a component of mineral oils that belongs to the branched alkanes . The name comes from the Latin : pristis ("sea monster"). Pristan is an inert and stable substance that occurs in all living things.
Occurrence
Pristan was first discovered in shark liver oil (content up to 14%). It is produced by bacteria , algae and higher plants, but is also found in various types of tissue in humans and cows, as well as in rat liver and wool wax . Marine occurrences are in zooplankton , lobsters , sharks , whales . Fossil oils and ancient sediments can contain pristan.
Stereoisomerism
| Natural pristan |
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 meso stereoisomer |
| Stereoisomers of synthetic pristane |
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-Pristane_FormulaV1.svg) ( R , R ) stereoisomer |
-Pristane_FormulaV1.svg) ( S , S ) stereoisomer |
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meso stereoisomer |
Due to the methyl groups on carbon atoms 6 and 10, pristane has two stereocenters . In naturally occurring pristan, one of these stereocenters shows an ( R ) configuration , the other ( S ) configuration , so it is a meso compound . meso- pristane has a mirror plane and is not chiral despite two stereocenters . Synthetic pristane consists of three stereoisomers :
- (6 R , 10 R ) -Pristan,
- (6 S , 10 S ) -Pristan and
- meso -Pristan.
The synthetic pristane contains the enantiomers (6 R , 10 R ) -pristane and (6 S , 10 S ) -pristane in a ratio of 1: 1; the proportion of meso- pristane fluctuates depending on the manufacturing process.
use
Pristan is used in industry as a lubricant , corrosion protection or transformer oil . It can also be used to attract termites . Its occurrence in mineral oil helps to identify oil pollutants, as it - like other compounds (so-called markers) - can be detected in different oils in characteristic proportions.
Pristan is also used in the medical field, where it is injected into the peritoneum of mice that are supposed to produce antibodies as an immunosuppressant . This is produced in mice plasmacytomas similar to a erythematosus lupus , which is useful for the study of autoimmune diseases is. It also creates arthritis in rats , thus helping in the study of this condition.
See also
Individual evidence
- ↑ Entry on PRISTANE in the CosIng database of the EU Commission, accessed on March 4, 2020.
- ↑ a b c Data sheet Pristan at Acros, accessed on February 26, 2010.
- ↑ a b Entry on Pristan. In: Römpp Online . Georg Thieme Verlag, accessed on May 29, 2014.
- ↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-480.
- ↑ a b c Pristane data sheet at Sigma-Aldrich , accessed on April 28, 2017 ( PDF ).
- ↑ EJ McKenna, RE Kallio: Microbial metabolism of the isoprenoid alkane pristane . In: Proceedings of the National Academy of Sciences . tape 68 , no. 7 , July 1971, p. 1552-1554 , PMID 4327007 ( PDF ).
- ↑ Meierhenrich : Amino acids and the asymmetry of life , Springer-Verlag, 2008. ISBN 978-3-540-76885-2 .
- ↑ Patent US6352703 : Compositions and methods for detecting and killing termites. Filed December 8, 1998 , published March 5, 2002 , Applicant: Louisiana State University, Inventor: Gregg Henderson, Jian Chen, Roger A. Laine.