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Eight (Z)-isomers of lycopene were prepared by stereocontrolled syntheses and fully characterized by '€1-NMR, "C-NMR, mass, and UVjVIS spectroscopy: (5Z)-, (72)

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Quality of life was markedly impaired in patients with permanent end ileostomy as compared with the general population. The main reasons were stoma-associated morbidity and nutritional deficiency syndromes. These findings highlight the importance of prevention, screening, and adequate treatment.

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Tetrahymanol, a rare triterpene from the gammacerane series, previously detected only in a few scattered eukaryotic taxa, has been isolated for the first time from the phototrophic bacterium Rhohpseudomonaspalustris. This extends the significance of geochemical markers from this series, which are abundant in marine sediments and palaeohypersaline environments.

The 1H-decoupled 1sC-NMR. spectra of 35 all-trans, 17 mono-cis vitamin A compounds (acetates, alcohols, aldehydes, acids and esters) and of one 11,13-di-cis compound (11,13di-cis rctinol) are reported. Included in this investigation are desmeth yl-, dcsmethylethyl, and aryl-vitamin A analogues and others as well as 30 reference compounds of smaller molecular weight. Furthermore, the 13C-NMR. spectra of 23 p-apo-and other carotenoids were studicd. A complete assignment of the signals of all 106 compounds to the specific carbon atoms was achieved by extensivc application of lanthanide shift reagents, mainly Yb(dpm)s, by CW-offset and selective 1H-decoupling experiments, by comparison of the shifts of related compounds, and in three cases by utilization of specifically deuteriatcd compounds (11,15,. Thc chemical shift differences between the cis-and trans-vitamin A compounds and the applicability of the shift reagents for the assignment of the W-NMR. spcctra arc discussed.

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