title: Structural studies of loteprednol etabonate and other analogs of prednisolone using NMR techniques.
abstract: Several structural analogs of prednisolone, prepared by esterification of the carboxylic and/or the C(17)-hydroxy group of 11 beta, 17 alpha-dihydroxy-3-oxo-androsta-1,4-diene-17 beta-carboxylic acid, were investigated by NMR. Step-by-step analysis of the 1H and 13C NMR spectra of these steroids, including proton-proton selective decoupling, nuclear Overhauser effect difference spectra, attached proton test, proton-carbon correlation (HETCOR), proton-proton correlation (COSY), and long-range proton-carbon decoupling (INAPT) techniques, led to unequivocal assignments of all their proton and carbon resonances. The stereochemical structure of loteprednol etabonate (chloromethyl 17 alpha-ethoxycarbonyloxy-11 beta-hydroxy-3-oxoandrosta-1,4-diene-17 beta-carboxylate, 1), a soft corticosteroid antiinflammatory drug, was proved to be analogous to prednisolone.
authors.affiliation: Pharmos Corporation, Alachua, Florida 32615, USA.
authors.forename: S
authors.initials: S
authors.lastname: Rachwal
authors.forename: E
authors.initials: E
authors.lastname: Pop
authors.forename: M E
authors.initials: ME
authors.lastname: Brewster
mesh_terms: D000730:Androstadienes / Q000138:chemical synthesis / Q000737:chemistry*; D000069559:Loteprednol Etabonate; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D011239:Prednisolone / Q000031:analogs & derivatives* / Q000737:chemistry*; D013329:Structure-Activity Relationship
chemical_list: D000730:Androstadienes; D011239:Prednisolone; D000069559:Loteprednol Etabonate