title: Synthesis and characterization of an epimer of tacrolimus, an immunosuppressive drug.
abstract: 8-Epitacrolimus (2), a new l-pipecolic acid macrolide lactone, was obtained by base-catalyzed epimerization of tacrolimus (FK-506, 1), an important immunosuppressive drug, and its structure determined by a single-crystal X-ray diffraction method. The compound was fully characterized by spectroscopic techniques. The epimer is of importance due to its potential biological effects as well as because of its possible formation during formulation, handling, and use of tacrolimus products.
authors.affiliation: Department of Medicinal Chemistry, Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark.
authors.forename: Dorthe M
authors.initials: DM
authors.lastname: Skytte
authors.forename: Karla
authors.initials: K
authors.lastname: Frydenvang
authors.forename: Liselotte
authors.initials: L
authors.lastname: Hansen
authors.forename: Peter G
authors.initials: PG
authors.lastname: Nielsen
authors.forename: Jerzy W
authors.initials: JW
authors.lastname: Jaroszewski
mesh_terms: D018360:Crystallography, X-Ray; D007166:Immunosuppressive Agents / Q000138:chemical synthesis / Q000737:chemistry; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D013237:Stereoisomerism; D016559:Tacrolimus / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D007166:Immunosuppressive Agents; D016559:Tacrolimus