Magnetic isotope effects (MIE) on the diastereoselectivity of the triplet [2+2]-photocycloaddition of benzaldehyde with 2,3-dihydrofuran are described for four substrate combinations. The MIE results from H/D exchange at the reactive carbons of either the aldehyde or the alkene, respectively, but also from deuteration of the aromatic positions of benzaldehyde. Weaker isotope effects on the diastereoselectivity were detected for the reaction of alpha-deuterated propionaldehyde.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/ja0356232 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Protein glycation compromises the bioavailability of milk protein-derived lysine in vivo in healthy adult males: a double-blind randomized cross-over trial.
Am J Clin Nutr
January 2025
Department of Human Biology, NUTRIM Institute of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, the Netherlands. Electronic address:
Background: Industrial processing and storage of milk products can strongly increase protein glycation level. Previously, we have reported that ingestion of highly glycated milk protein attenuates the post-prandial rise in plasma lysine concentrations when compared to the ingestion of an equivalent amount of milk protein with a low glycation level. Whether the attenuated increase in plasma lysine availability is attributed to compromised protein digestion and subsequent lysine absorption remains to be established.
View Article and Find Full Text PDFQuantifying the sources and health risks of groundwater nitrate via dual NO isotopes and Monte Carlo simulations in a developed planting-breeding area.
Ecotoxicol Environ Saf
January 2025
College of Resources and Environmental Sciences, Henan Agricultural University, Zhengzhou 450046, China. Electronic address:
Nitrate (NO) pollution in groundwater is a worldwide environmental issue, particularly in developed planting-breeding areas where there is a substantial presence of nitrogen-related sources. Here, we explored the key sources and potential health risks of NO in a typical planting-breeding area in the North China Plain based on dual stable isotopes and Monte Carlo simulations. The analysis results revealed that the NO concentration ranged from 0.
View Article and Find Full Text PDFRiverine songbirds capture high levels of atmospheric mercury pollution from brown food webs in forests by mercury isotopic evidence.
J Hazard Mater
January 2025
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Elevated methylmercury (MeHg) exposure poses significant risks to bird health, behavior, and reproduction. Still, the risk of MeHg exposure to forest birds, accounting for over 80 % of the world's bird species, is poorly understood. This study combines Hg isotopes and video analysis, aiming to assess MeHg exposure risks to a forest riverine songbird, the spotted forktail (Enicurus maculatus) from a remote subtropical montane forest.
View Article and Find Full Text PDFFuzzy logic modelling of the pollution pattern of potentially toxic elements and naturally occurring radionuclide materials in quarry sites in Ogun State, Nigeria.
Environ Geochem Health
January 2025
Department of Chemistry, Chulalongkorn University, Bangkok, Thailand.
The accumulation pattern of some inorganic pollutants in quarry sites around Ogun State was modeled using a Fuzzy comprehensive assessment (FCA). Potentially toxic elements (PTEs) and naturally occurring radionuclides materials (NORMs) were assessed from soil samples collected from ten quarry sites in three districts (Odeda, Ajebo, and Ijebu Ode) in Ogun State. Three (3) NORMs ( K, U, Th) were assessed using gamma spectrometer with a NaI detector while ten (10) PTEs (As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) were determined by digestion method using Inductively coupled plasma optical emission spectrophotometer.
View Article and Find Full Text PDFTwo-Dimensional Liquid Chromatography-Isotope Ratio Mass Spectrometry Opens New Possibilities in the Field of Compound-Specific Stable Isotope Analysis.
Anal Chem
January 2025
Instrumental Analytical Chemistry, University of Duisburg-Essen, Universitätsstraße 5, 45141 Essen, Germany.
Compound-specific stable isotope analysis (CSIA) using liquid chromatography-isotope ratio mass spectrometry (LC-IRMS) is a powerful tool for determining the isotopic composition of carbon in analytes from complex mixtures. However, LC-IRMS methods are constrained to fully aqueous eluents. Previous efforts to overcome this limitation were unsuccessful, as the use of organic eluents in LC-IRMS was deemed impossible.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!