title: On the stereochemistry and biosynthesis of lipoxin B.
abstract: Lipoxin B (LXB) was prepared by incubation of (15S)-15-hydroperoxy-5,8,11-cis-13-trans-icosatetraenoic acid (15-HPETE) with human leukocytes. Comparison with a number of trihydroxyicosatetraenes prepared by total synthesis showed that biologically derived LXB is (5S,14R,15S)-5,14,15-trihydroxy-6,10,12-trans-8-cis-icosatetraenoi c acid. Two isomers of LXB were identified by using an improved isolation procedure. These compounds were shown to be (5S,14R,15S)-5,14,15-trihydroxy-6,8,10,12-trans-icosatetraenoic acid (8-trans-LXB) and (5S,14S,15S)-5,14,15-trihydroxy-6,8,10,12-trans-icosatetraenoic acid [(14S)-8-trans-LXB]. Experiments with 18O2 showed that formation of LXB and its two isomers occurred with incorporation of molecular oxygen at C-5 but not at C-14. These results together with the finding that (15S)-hydroxy-5,8,11-cis-13-trans-icosatetraenoic acid (15-HETE) is a precursor of LXB compounds in activated leukocytes suggest that 15-hydroxy-5,6-epoxy-7,9,13-trans-11-cis-icosatetraenoic acid or its equivalent is a common intermediate in the biosynthesis of LXB and its two isomers.
authors.forename: C N
authors.initials: CN
authors.lastname: Serhan
authors.forename: M
authors.initials: M
authors.lastname: Hamberg
authors.forename: B
authors.initials: B
authors.lastname: Samuelsson
authors.forename: J
authors.initials: J
authors.lastname: Morris
authors.forename: D G
authors.initials: DG
authors.lastname: Wishka
mesh_terms: D001095:Arachidonic Acids / Q000378:metabolism; D001792:Blood Platelets / Q000378:metabolism; D000001:Calcimycin / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000032:analysis / Q000096:biosynthesis* / Q000378:metabolism; D007536:Isomerism; D007962:Leukocytes / Q000378:metabolism*; D015289:Leukotrienes; D008054:Lipid Peroxides / Q000378:metabolism; D044045:Lipoxins; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
chemical_list: D001095:Arachidonic Acids; D006893:Hydroxyeicosatetraenoic Acids; D015289:Leukotrienes; D008054:Lipid Peroxides; D044045:Lipoxins; D000001:Calcimycin; C025086:15-hydroperoxy-5,8,11,13-eicosatetraenoic acid; C025984:15-hydroxy-5,8,11,13-eicosatetraenoic acid; C042651:lipoxin B4