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Triketone herbicides are inhibitors of 4-hydroxyphenylpyruvate dioxygenase (HPPD), a key enzyme of the tyrosine transformation pathway, common for plants and animals. One of these herbicides, 2-[2-nitro-4-(trifluoromethyl)benzoyl]-1,3-cyclohexanedione (NTBC), is so selective and efficient that it can be applied as a medicine in a hereditary metabolic disease - tyrosinemia type I. In this paper the available information concerning the molecular mechanism of HPPD inhibition by NTBC, originating from experimental investigations as well as theoretical modeling, has been collected. It is supplemented by results of additional theoretical DFT and/or MP2 calculations of the energetic effects of individual elementary molecular transformations. All these data are discussed and a consistent picture of HPPD inhibition by NTBC is proposed.
 A range of inborn metabolic diseases result in abnormal accumulation of acylglycines in body fluids. Therefore, detection of these metabolites is important for diagnostic purposes. 1H and 13C NMR spectroscopies have successfully been applied for both qualitative and quantitative determinations of various acylglycines in urine samples from patients suffering from metabolic diseases connected with excretion of these compounds. Various acylglycines were identified in test urine samples from 15 patients suffering from five different metabolic diseases, providing information which could be crucial for their diagnoses. The paper reports complete 1H and 13C NMR data of 11 acylglycines, which is essential for this type of NMR analysis of body fluids. NMR spectroscopy has been proven effective in determining the presence as well as the levels of acylglycines in urine. The proposed method is rapid, simple and requires minimal sample treatment.
Organic extracts of six urine samples from children treated with nitisinone, a medicine against tyrosinemia type I, were investigated by 1H and 19F NMR spectroscopy. The presence of unchanged 2-[2-nitro-4-(trifluoromethyl)benzoyl]cyclohexane-1,3-dione (NTBC), 6-hydroxy-2-[2-nitro-4-(trifluoromethyl)benzoyl]cyclohexane-1,3-dione (NTBC-OH) and 2-nitro-4-trifluoromethylbenzoic acid (NTFA) as well as a few other unidentified compounds containing CF3 group was documented.
High-resolution  1H NMR spectroscopy of body fluids has proved to be very useful in diagnostics of inherited metabolic diseases, whereas  13C NMR remains almost unexploited. In this paper the application of  13C NMR spectroscopy of fivefold concentrated urine samples for diagnosis of selected metabolic diseases is reported. Various marker metabolites were identified in test urine samples from 33 patients suffering from 10 different diseases, providing information which could be crucial for their diagnoses. Spectra were accumulated for 2 h or overnight when using spectrometers operating at 9.4 or 4.7 T magnetic fields, respectively. Interpretation of the measurement results was based on a comparison of the peak positions in the measured spectrum with reference data. The paper contains a table with  13C NMR chemical shifts of 73 standard compounds. The method can be applied individually or as an auxiliary technique to  1H NMR or any other analytical method.
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