52947-00-9Relevant academic research and scientific papers
Quantitation of Nine Lactones in Dairy Cream by Stable Isotope Dilution Assays Based on Novel Syntheses of Carbon-13-Labeled γ-Lactones and Deuterium-Labeled δ-Lactones in Combination with Comprehensive Two-Dimensional Gas Chromatography with Time-of-Flight Mass Spectrometry
Schütt, Jessica,Schieberle, Peter
, p. 10534 - 10541 (2017/12/15)
Lactones are well-known aroma compounds in, e.g., fruits and fermented foods as well as in dairy products, such as cream or milk powders. The latter are often used in confectionary products, e.g., milk chocolate. Lactones are suggested to contribute to the distinct aroma of dairy products and have also been reported in milk chocolate. However, data on their contribution to the overall aroma of this type of chocolate are scarce. As a result of their pH-dependent instability and their low volatility, a reliable quantitation of lactones is a challenge. Thus, to allow for a quantitation of nine lactones in one single comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry in electron ionization mode run, new synthetic routes were developed for five carbon-13-labeled γ-lactones and four deuterium-labeled δ-lactones, with the isotope label in the ring to be used in stable isotope dilution assays. The concentrations of the nine lactones were then analyzed in raw and pasteurized cream as well as in a heat-treated raw cream. δ-Dodecalactone and δ-decalactone showed the highest concentrations in both the raw and pasteurized cream. In the latter, δ-dodecalactone reached a 2.5-fold higher concentration compared to the raw cream. Subsequent heat treatments in a lab scale showed a further increase by factors of 13 and 19, respectively, suggesting a high potential of lactone precursors in cream. The results serve as a basis for further studies on lactone formation in other thermally processed products, such as milk chocolate.
Synthesis of a panel of carbon-13-labelled (glyco)sphingolipids
Wisse, Patrick,Gold, Henrik,Mirzaian, Mina,Ferraz, Maria J.,Lutteke, Ginger,Van Den Berg, Richard J. B. H. N.,Van Den Elst, Hans,Lugtenburg, Johan,Van Der Marel, Gijsbert A.,Aerts, Johannes M. F. G.,Codée, Jeroen D. C.,Overkleeft, Herman S.
, p. 2661 - 2677 (2015/04/27)
The synthesis of a focussed library of sphingolipids differing in the number and position of 13C labels is described. The synthesised sphingolipids differ in substitution at both the sphingosine amine (either palmitoylated or unmodified) and the sphingosine primary hydroxyl (unmodified or glycosylated). Moreover, 13C atoms are incorporated into either the sphingosine or the palmitate moiety, or both. This set of compounds is intended for use in relative quantitative lipidomics studies to gain insight into sphingolipid metabolism in healthy and diseased (lysosomal storage disorders) patients and animal models. The synthesis of a focussed library of sphingolipids differing in the number and position of 13C labels is described. 13C atoms are incorporated into either the sphingosine or the palmitate moiety, or both. This set of compounds is intended for use in relative quantitative lipidomics studies to gain insight into sphingolipid metabolism.
On the biosynthetic origin of methoxymalonyl-acyl carrier protein, the substrate for incorporation of "glycolate" units into ansamitocin and soraphen A
Wenzel, Silke C.,Williamson, Rachel M.,Gruenanger, Christian,Xu, Jun,Gerth, Klaus,Martinez, Rodolfo A.,Moss, Steven J.,Carroll, Brian J.,Grond, Stephanie,Unkefer, Clifford J.,Mueller, Rolf,Floss, Heinz G.
, p. 14325 - 14336 (2008/03/13)
Feeding experiments with isotope-labeled precursors rule out hydroxypyruvate and TCA cycle intermediates as the metabolic source of methoxymalonyl-ACP, the substrate for incorporation of "glycolate" units into ansamitocin P-3, soraphen A, and other antibi
The preparation of all-trans uniformly 13C-labeled retinal via a modular total organic synthetic strategy. Emerging central contribution of organic synthesis toward the structure and function study with atomic resolution in protein research
Creemers, Alain F. L.,Lugtenburg, Johan
, p. 6324 - 6334 (2007/10/03)
Uniformly [13C20]-labeled all-trans-retinal (1) has been prepared via a convergent modular total organic strategy with high isotope incorporation (>99%) and without isotope dilution starting from commercially available 99% enriched
Chemo-enzymatic synthesis of thymidine 13C-labelled in the 2'- deoxyribose moiety
Ouwerkerk, Niels,Van Boom, Jacques H.,Lugtenburg, Johan,Raap, Jan
, p. 861 - 866 (2007/10/03)
A synthesis of [3',4'-13C2]thymidine (1) is described in which [13C2]acetic acid (2) is converted into the nucleoside in twelve steps with 9% overall yield. D-2-Deoxyribose-5-phosphate aldolase (DERA, EC 4.1.2.4
