Proton-observed carbon-edited (POCE) NMR spectroscopy is commonly used to measure 13C labeling with higher sensitivity compared to direct 13C NMR spectroscopy, at the expense of spectral resolution. For weakly coupled first-order spin systems, the multiplet signal at a specific proton chemical shift in POCE spectra directly reflects 13C enrichment of the carbon attached to this proton. The pres...

The non-extractable residues of the fungicide cyprodinil formed in heterotrophic cell suspension cultures of wheat were studied by application of [2-pyrimidyl-14C] or [2-pyrimidyl-13C]cyprodinil. The main objective was to examine whether solid-state and liquid 13C NMR spectroscopy can be used to examine plant bound residues of pesticides. For 14C experiments, wheat suspensions grown on glucose ...

A generalized 2D correlation NMR (GEN2D-NMR) scheme capable of substantially reducing the experimental time for two-dimensional correlation NMR experiments is described. The experimental time used in GEN2D-NMR is shortened to less than one-tenth of that required in traditional double Fourier transform 2D-NMR (FT2D-NMR) for a 13C-13C spin diffusion experiment for Nephila edulis spider threads. E...

The hepatic metabolism of 1,omega-dodecanedioic acid, a physiologically relevant representative of the medium-chain dicarboxylic acid family, has been studied by a combination of in vivo and in vitro 13C and 1H NMR spectroscopic techniques. Rats in different nutritional or hormonal situations were infused with [1,12-13C2]- or [1,2,11,12-13C4]dodecanedioic acid, and the kinetics of 13C label app...

The biosynthesis of maduramicin alpha and beta in a culture of Actinomadura yumaensis has been studied using 13C, 14C and 18O labeled precursors. The alpha component of this recently discovered polyether antibiotic, containing forty-seven carbon atoms in a seven-ring system, is derived from eight acetate, seven propionate and four methionine molecules. The beta component which is missing one me...

3-1. 1a–Pd Complexes 8 3-1-1. Detailed NMR of 1a for peak assignments 8 3-1-2. Detailed NMR of 1a/Pd for peak assignments 10 3-1-3. Detailed NMR of (1a)2/Pd for peak assignments 13 3-1-4. Stacked 1H and 13C NMR of 1a, 1a/Pd, and (1a)2/Pd 17 3-2. 1b–Pd Complex 19 3-2-1. Detailed NMR of 1b for peak assignments 19 3-2-2. Detailed NMR of (1b)2/Pd for peak assignments 23 3-2-3. Stacked 1H and 13C NM...

1-{β-[3-(4-Methoxy-phenyl)propoxy]-4-methoxyphenethyl}-1H-imidazole hydrochloride 7, or SKF-96365, was synthesized in four steps with an overall yield of 9%. The structure of 7 was confirmed by 1H-, 13C-NMR, HRMS, and elemental analysis. The intermediates 3 and 4 were also isolated and characterized by 1H-, 13C-NMR, and HRMS.

Silyl and acetyl derivatives of sporopollenin from the pollen of Typha angustifolia L. were prepared. The derivatized products were readily soluble in piperidine-d11 and could be investigated employing one- and two-dimensional proton and carbon NMR (nuclear magnetic resonance) spectroscopy (1H,1H-COSY and 13C,1H-HETCOR techniques). For the first time, a two dimensional 13C,1H-HETCOR NMR spectru...

Nine different artificial neural networks were trained with the spherically encoded chemical environments of more than 500000 carbon atoms to predict their 13C NMR chemical shifts. Based on these results the PC-program "C_shift" was developed which allows the calculation of the 13C NMR spectra of any proposed molecular structure consisting of the covalently bonded elements C, H, N, O, P, S and ...

The effects of 3-O-methyl-D-glucose (3-OMG) on subcutaneously implanted murine radiation-induced fibrosarcoma 1 tumor were examined with 2H, 13C, and 31P nuclear magnetic resonance (NMR) in situ. Using 31P NMR, changes in tumor high-energy phosphate metabolism were monitored for 2.5 h after i.p. administration of 3-OMG (8.1 g/kg body weight); tumor pH decreased by a mean maximum of 0.52 +/- 0.0...