20701-68-2Relevant articles and documents
Stereochemistry of C18 monounsaturated cork suberin acids determined by spectroscopic techniques including 1H-NMR multiplet analysis of olefinic protons
Santos, Sara,Gra?a, José
, p. 192 - 200 (2014)
Introduction Suberin is a biopolyester responsible for the protection of secondary plant tissues, and yet its molecular structure remains unknown. The C18:1 ω-hydroxyacid and the C18:1 α,ω-diacid are major monomers in the suberin structure, but the configuration of the double bond remains to be elucidated. Objective To unequivocally define the configuration of the C18:1 suberin acids. Methods Pure C18:1 ω-hydroxyacid and C18:1 α,ω-diacid, isolated from cork suberin, and two structurally very close C18:1 model compounds of known stereochemistry, methyl oleate and methyl elaidate, were analysed by NMR spectroscopy, Fourier transform infrared (FTIR) and Raman spectroscopy, and GC-MS. Results The GC-MS analysis showed that both acids were present in cork suberin as only one geometric isomer. The analysis of dimethyloxazoline (DMOX) and picolinyl derivatives proved the double bond position to be at C-9. The FTIR spectra were concordant with a cis-configuration for both suberin acids, but their unambiguous stereochemical assignment came from the NMR analysis: (i) the chemical shifts of the allylic 13C carbons were shielded comparatively to the trans model compound, and (ii) the complex multiplets of the olefinic protons could be simulated only with 3JHH and long-range 4JHH coupling constants typical of a cis geometry. Conclusion The two C18:1 suberin acids in cork are (Z)-18-hydroxyoctadec-9-enoic acid and (Z)-octadec-9-enedoic acid. Copyright 2013 John Wiley & Sons, Ltd. The two C18:1 cork suberin ω-hydroxyacid and α,ω-diacid were proved to have a cis configuration: (Z)-18-hydroxyoctadec-9-enoic acid and (Z)-octadec-9-enedoic acid. Their double bond stereochemistry was elucidated by spectroscopic techniques, namely 1H-NMR and 13C-NMR. The chemical shifts of the olefinic and allylic protons and of the allylic carbons were diagnostic, and the 1H-NMR multiplets of the olefinic protons could only be simulated using 3JHH and long-range 4J HH coupling constants typical of the cis configuration. The revealed stereochemistry of this two major suberin monomers brings a new insight into the mostly unknown suberin macromolecular structure. Copyright
ESTERAMINES AND DERIVATIVES FROM NATURAL OIL METATHESIS
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Page/Page column 22; 32, (2012/05/20)
Esteramine compositions and their derivatives are disclosed. The esteramines comprise a reaction product of a metathesis-derived C10-C17 monounsaturated acid, octadecene-1,18-dioic acid, or their ester derivatives with a tertiary alkanolamine. Derivatives made by quaternizing, sulfonating, alkoxylating, sulfating, and/or sulfitating the esteramines are also disclosed. In one aspect, the ester derivative of the C10-C17 monounsaturated acid or octadecene-1,18-dioic acid is a lower alkyl ester. In other aspects, the ester derivative is a modified triglyceride made by self-metathesis of a natural oil or an unsaturated triglyceride made by cross-metathesis of a natural oil with an olefin. The esteramines and derivatives are valuable for a wide variety of end uses, including cleaners, fabric treatment, hair conditioning, personal care (liquid cleansing products, conditioning bars, oral care products), antimicrobial compositions, agricultural uses, and oil field applications.
METHOD FOR PREPARING LONG-CHAIN HYDROXYACIDS, DIACIDS AND OLIGOMERS AND POLYLMERS THEREOF
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Page/Page column 15, (2010/04/03)
A method and process for the preparation of ricinoleic acid analogs and oligomers and polymers containing such ricinoleic acid analogs.
