Stereospecific elimination of hydrogen at C-10 in eicosapentaenoic acid during the conversion to leukotriene C5

S Hammarström
1983 Journal of Biological Chemistry  
(10L)- and (10D)-[1-14C, 10-3H]5,8,11,14,17-eicosapentaenoic acids were synthesized to investigate mechanistic and stereochemical aspects of leukotriene biosynthesis. Experiments with mastocytoma cells showed that a hydrogen is stereospecifically eliminated from C-10 during the conversion of eicosapentaenoic acid to leukotriene C5. The hydrogen lost has the pro-S (D) configuration. 5-Hydroxy-6,8,11,14,17-eicosapentaenoic acid, formed in the same experiments, was enriched in tritium when the
more » ... ), but not when the (10L), isomer of labeled eicosapentaenoic acid was used. This indicates that oxygenation of the acid at C-5 occurred before the elimination of hydrogen and suggests that removal of the pro-S hydrogen at C-10 in 5-hydroperoxy-6,8,11,14,17-eicosapentaenoic acid initiates its transformation to trans-5(S),6(S)-oxido-7,9-trans-11,14,17-cis-eicosapentaenoic acid (leukotriene A5).
pmid:6296095 fatcat:m4mfunqavngunpjdaesmau6c64