Crocetin derivatives were extracted and purified from saffron stigmas and gardenia fruits by reversed-phase HPLC. They were characterized by 1D and 2D 1H and 13C NMR and UV−vis spectroscopies and mass spectrometry. The following compounds were found in saffron: all-trans-crocetin di(β-d-gentiobiosyl) ester 1a, all-trans-crocetin β-d-gentiobiosyl-β-d-glucosyl ester 1b, all-trans-crocetin di(β-d-glucosyl) ester 1c, and all-trans-crocetin mono(β-d-gentiobiosyl) ester 1d, as well as 13-cis-crocetin di(β-d-gentiobiosyl) ester 2a and 13-cis-crocetin β-d-gentiobiosyl-β-d-glucosyl ester 2b. Compounds 1a, 1b, and 1d were also present in gardenia, in addition to all-trans-crocetin mono(β-d-glucosyl) ester 1e. Keywords: Saffron; gardenia; Crocus sativus; Gardenia jasminoides; crocetin derivatives; carotenoid pigments; mass spectrometry; UV − vis spectroscopy; NMR spectroscopy
A group of 25 agencies from Canada and the United States conducted a major offshore burn experiment near Newfoundland, Canada. Two lots of oil, about 50 cubic meters (50 tons) each, were released into a fireproof boom. Each burn lasted over an hour and was monitored for emissions and physical parameters. Over 200 sensors or samplers were employed to yield data on over 2000 parameters or substances. The operation was extensive; more than 20 vessels, 7 aircraft and 230 people were involved in the operation at sea. The quantitative analytical data show that the emissions from this in-situ oil fire were less than expected. All compounds and parameters measured more than about 150 meters from the fire were below occupational health exposure levels; very little was detected beyond 500 meters. Pollutants were found to be at lower values in the Newfoundland offshore burn than they were in previous pan tests. Polyaromatic hydrocarbons (PAHs) were found to be lower in the soot than in the starting oil and were consumed by the fire to a large degree. Particulates in the air were measured by several means and found to be of concern only up to 150 meters downwind at sea level. Combustion gases including carbon dioxide, sulphur dioxide, and carbon monoxide did not reach levels of concern. Volatile organic compounds (VOCs) were abundant, however their concentrations were less than emitted from the nonburning spill. Over 50 compounds were quantified, several at levels of concern up to 150 meters downwind. Water under the burns was analyzed; no compounds of concern could be found at the detection level of the methods employed. Toxicity tests performed on this water did not show any adverse effect. The burn residue was analyzed for the same compounds as the air samples. Overall, indications from these burn trials are that 150 meters or farther from the burn source emissions from in-situ burning are lower than health criteria levels.
The role of ion-molecule and ion-radical complexes in the fragmentation of odd electron ions is a topic of considerable current interest. Morton' has defined these species as "non-covalently bonded aggregates of an ion with one (or more) neutral molecules in which one of the partners rotates freely (or nearly so) in all directions." A good, well established example of an ion-molecule complex is the ethene ion-water molecule pair which has been thoroughly described by theory and experiment2. The second type of complex is well represented in the fragmentation behaviour of the alkyl phenyl ethers3v4. Both systems have been demonstrated by experimental investigations to fall within the above definition.In general, it is not easy by experiment alone to obtain unequivocal evidence for the participation of such complexes in ion fragmentations. A detailed recent study by ourselvesS failed to provide a satisfactory complete mechanism for the principal fragmentation of metastable ionized neopentanol, 1: namely, loss of CH,OH. In D-labelled neopentanol, the fragment ion abundances were not in random statistical ratios but nevertheless indicated a major loss of positional identity of H and D. It was concluded however, in partial agreement with the earlier proposal of Hammerum and Audier6, that the final reacting configuration is best described as an ion/molecule complex between ionized methylpropene and methanol. The suggested involvement6 of an ionhadical complex between the t-butyl cation and a 'CH,OH radical was considered unproven and the loss of positional identity among H and D atoms was ascribed to the participation of distonic and ylid ions'. A complete reaction mechanism for the system proved elusive and in particular, observations of the deuterium labelled distonic [C,H,,O]+'ion, [(CH,),C'CH,O+(H)CD,] 4, (the numbering here is that used in ref. 5) and its relationship with ionized neopentanol remained unexplained.We report here the behaviour of another [C,H,,O]+' ion, generated by the loss of CH,O from ionized 2-t-butoxyethanol, 6, which enables us to present a satisfactory overall mechanism for the behaviour of the neopentanol molecular ion, and also ion 4. This new mechanism includes the t-butyl cationhydroxymethyl radical complex originally proposed by Hammerum and Audier', but for which direct experimental evidence was lacking. Results and DiscussionThe electron impact (EI) mass spectrum of (CH,),COCH,CH,OH contains small peaks at m/z 87 [C,H,,O]+ and m/z 88 [C,H,,O]+', of abundance 8% and 2% of the base peak m/z 57, [C,&]+. The [C5HI2O]+' ion is formed by loss of CH20 from the molecular ion. The peaks m/z 87 and m/z 88 are shifted to m/z 89 and 90 and are at m/z 87 and m/z 89 in the mass spectra of (CH,),COCD,CD,OH and (CH,),COCH,CH,OD respectively. The m/z 88 ion [C,H,,O]+', is assigned the structure 5 as shown below
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