title: Air oxidation of 17-hydroxycorticosteroids catalyzed by cupric acetate: formation of hemiacetal dimers.
abstract: Hydrocortisone, cortexolone, hydrocortisone-17-butyrate, and budesonide were oxidized into alpha-ketoaldehydes by air exposure in the presence of Cu(OAc)(2). When free hydroxyl functions were present at position 17, hydrocortisone and cortexolone, the formed oxidation products, were identified as hemiacetal dimeric structures involving the free hydroxyl functions at position 17 and the newly formed aldehydes at position 21. Dimeric structures were established by using 1H913C0 correlations (HSQC and HMBC) and 1H-1H correlations (COSY and ROESY). The hemiacetal function was further confirmed by reaction of the dimer formed from hydrocortisone with two equivalents of 3-methyl-2-benzotriazolinone hydrazine (MTBH), giving quantitatively two equivalents of the 3-methyl-2-benzotriazolinone hydrazone of 21-dehydrohydrocortisone. When no free hydroxyl function was present as in the case of hydrocortisone-17-butyrate and budesonide, the expected alpha-ketoaldehydes were obtained.
authors.affiliation: Laboratoire de Dermatochimie, UMR 7123, Clinique Dermatologique, CHU, Université Louis Pasteur, Strasbourg, Cedex F-67091, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Arbez-Gindre
authors.forename: Valérie
authors.initials: V
authors.lastname: Berl
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Lepoittevin
mesh_terms: D015065:17-Hydroxycorticosteroids / Q000737:chemistry* / Q000378:metabolism; D000080:Acetals / Q000737:chemistry* / Q000302:isolation & purification; D000388:Air; D000447:Aldehydes / Q000737:chemistry / Q000302:isolation & purification; D002384:Catalysis; D019281:Dimerization; D019906:Nuclear Magnetic Resonance, Biomolecular; D009942:Organometallic Compounds / Q000378:metabolism*; D010084:Oxidation-Reduction
chemical_list: D015065:17-Hydroxycorticosteroids; D000080:Acetals; D000447:Aldehydes; D009942:Organometallic Compounds; C015092:cupric acetate