Synthesis and use of deuterated palmitic acids to decipher the cryptoregiochemistry of a Delta13 desaturation.
The synthesis of two hexadeuterated palmitic acids differing in the position of the diagnostic labels, and their use to decipher the cryptoregiochemistry of a Delta13 desaturation are described. A dithiane and a triple bond functionalities were used to introduce the diagnostic (C13 or C14) and tagging (C8 and C9) labels, respectively, in the palmitic acid skeleton. Using these probes, the cryptoregiochemistry of the Delta13 desaturation involved in the biosynthesis of Thaumetopoea pityocampa sex pheromone was studied by means of kinetic isotope effect determinations. Transformation of both (Z)-11-hexadecenoic and 11-hexadecynoic acids into (Z, Z)-11,13-hexadecadienoic and (Z)-13-hexadecen-11-ynoic acids, respectively, is initiated by abstraction of the hydrogen atom at the C13 position, followed by the fast elimination of the C14 hydrogen to give the double bond.
Abad
José-Luis
JL
Departamento de Química OrgAnica Biológica, Instituto de Investigaciones Químicas y Ambientales de Barcelona, Consejo Superior de Investigaciones Científicas, J. Girona 18, 08034, Barcelona, Spain. jlaqob@iiqab.csic.es
Serra
Montserrat
M
Camps
Francisco
F
Fabriàs
Gemma
G
D000818:Animals; D003903:Deuterium / Q000737:chemistry*; D044943:Fatty Acid Desaturases / Q000737:chemistry*; D007554:Isotopes / Q000737:chemistry; D007700:Kinetics; D008956:Models, Chemical; D009036:Moths / Q000502:physiology; D010169:Palmitic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D012724:Sex Attractants / Q000096:biosynthesis / Q000737:chemistry; D013237:Stereoisomerism
D007554:Isotopes; D010169:Palmitic Acids; D012724:Sex Attractants; C093821:hexadecenoic acid; D003903:Deuterium; D044943:Fatty Acid Desaturases