title: Heterocyclic analogs of xanthiones: 5,6-fused 3-methyl-1-phenylpyrano[2,3-c]pyrazol-4(1H) thiones-synthesis and NMR ((1)H, (13)C, (15)N) data.
abstract: Various [5,6]pyrano[2,3-c]pyrazol-4(1H)-thiones were synthesized in high yields by treatment of the corresponding [5,6]pyrano[2,3-c]pyrazol-4(1H)-ones with Lawesson's reagent. Detailed NMR spectroscopic studies were undertaken of the title compounds. Complete and unambiguous assignment of chemical shifts ((1)H, (13)C, (15)N) and coupling constants ((1)H,(1)H; (13)C,(1)H) was achieved by the combined application of various one- and two-dimensional (1D and 2D) NMR spectroscopic techniques. Unequivocal mapping of most (13)C,(1)H spin coupling constants is accomplished by 2D (delta, J) long-range INEPT spectra with selective excitation.
authors.affiliation: Department of Drug and Natural Product Synthesis, University of Vienna, A-1090 Vienna, Austria.
authors.forename: Valerie
authors.initials: V
authors.lastname: Huemer
authors.forename: Gernot A
authors.initials: GA
authors.lastname: Eller
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Holzer
mesh_terms: D002247:Carbon Isotopes / Q000737:chemistry; D006571:Heterocyclic Compounds / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D009587:Nitrogen Isotopes / Q000737:chemistry; D011522:Protons; D013871:Thiones / Q000138:chemical synthesis*
chemical_list: D002247:Carbon Isotopes; D006571:Heterocyclic Compounds; D009587:Nitrogen Isotopes; D011522:Protons; D013871:Thiones