Abstract
Abstractγ‐Stearidonic acid, 18:4n‐6, a potential product of β‐oxidation of arachidonic acid (20:4n‐6), was only recently positively identified in a living organism—a thermophilic cyanobacterium Tolypothrix sp., albeit at low levels, whilst some indirect evidence suggests its wider presence, e.g. in a unicellular marine alga. We have prepared 18:4n‐6 using an iodolactonisation chain‐shortening approach from 22:5n‐6 and obtained its 1H‐, 13C‐, COSY‐ and HSQC NMR spectra, with 18:5n‐3 spectra also recorded for a comparison. The GC and GC‐MS behaviour of its methyl ester was also studied. Like another Δ3 polyunsaturated acid, octadecapentaenoic (18:5n‐3), 18:4n‐6 rapidly yields 2‐trans isomer upon formation of dimethyloxazoline derivative. On a polar ionic liquid phase (SLB‐IL100, 200 °C) the methyl ester could be mistaken for 18:3n‐3, while on methylsilicone phase (BP1, 210 °C) it eluted ahead of 18:3n‐6 and 18:4n‐3, suggesting that when present it may be easily misidentified during GC analysis of fatty acids.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
