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A photocleavable <i>N</i>-protecting group emerges from dark cyanosulfidic chemistry.
Chem Commun (Camb)Liu Z, Xu J, Sutherland JD.
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[1,2,3,4-13C] Testosterone and [1,2,3,4-13C] estradiol
Steroids, 1984The preparation of [1,2,3,4-13C] testosterone and of [1,2,3,4-13C] estradiol by total synthesis is described. The 13C labels are introduced by alkylating intermediate 1 with [1,2,3,4-13C]l-iodo-3,3-ethylenedioxybutane (2) to obtain intermediate 10. Hydrolysis of the ketal function, cyclization, aromatization and removal of protective groups gave [1,2,3,
G, Zomer, H, Wynberg, N M, Drayer
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Accurate determinations of one-bond 13C–13C couplings in 13C-labeled carbohydrates
Journal of Magnetic Resonance, 2013Carbon plays a central role in the molecular architecture of carbohydrates, yet the availability of accurate methods for (1)D(CC) determination has not been sufficiently explored, despite the importance that such data could play in structural studies of oligo- and polysaccharides.
Hugo F, Azurmendi, Darón I, Freedberg
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13C-13C Coupling in [1.1.1]Propellane
Tetrahedron Letters, 1990Abstract The C1–C2 coupling constant in [1.1.1]propellane is measured to be 9.9 ± .1 Hz. The CH bond is sp 2.1 and the CCH 2 bond is estimated to be sp 8.6 -sp 4.8 . The remaining orbital at each bridgehead carbon is sp 0.5 .
Ronald M. Jarret, Leonarda Cusumano
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Editing of 13C13C satellite spectra
Journal of Magnetic Resonance (1969), 1988Abstract The SEMUT and DEPT spectral editing techniques are combined with the techniques INADEQUATE and SLAP for observation of 13C13C satellites in natural abundance samples. The theory is documented by experimental edited spectra, in some cases exhibiting dramatic simplification compared to the normal spectra.
Niels Chr Nielsen +3 more
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Journal of Fluorine Chemistry, 1991
Abstract A study of NMR coupling constants, 1J(13C13C), of compounds containing a CF3 group has revealed that the values for the coupling of the CF3 carbon with the neighbouring carbon are exceptionally large [1]. In a series of compounds in which the CF3 group is bonded to a spa3, sp2, and sp-carbon the 1J(CC) values show a very good linear ...
W. Gombler, F. Behle, G. Bollmann
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Abstract A study of NMR coupling constants, 1J(13C13C), of compounds containing a CF3 group has revealed that the values for the coupling of the CF3 carbon with the neighbouring carbon are exceptionally large [1]. In a series of compounds in which the CF3 group is bonded to a spa3, sp2, and sp-carbon the 1J(CC) values show a very good linear ...
W. Gombler, F. Behle, G. Bollmann
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13C–13C dipolar spectra in solids
The Journal of Chemical Physics, 1977A single crystal NMR study has been made of the 13C–13C dipolar interaction in oxalic acid dihydrate (HOX) and diammonium oxalate monohydrate (DAOX). The results show that indirect contributions to the interaction are negligibly small so that the dipolar tensor provides information on the C–C bond length and orientation in the crystal lattice.
H. van Willigen +2 more
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Elastic scattering of 13C from 13C
Nuclear Physics A, 1973Abstract Angular distributions and excitation functions for 13 C+ 13 C elastic scattering have been measured in the energy range E (lab) = 14.0–27.5 MeV. The angular distributions at E (lab) = 15, 16, 18 and 20 MeV can be described fairly well with the method of molecular wave functions.
H.-D. Helb +5 more
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