A highly efficient and expedient method for the synthesis of 4,5-disubstituted oxazoles has been developed directly from carboxylic acids, employing a stoichiometric amount of the easy-to-access and stable triflylpyridinium reagent. The overall transformation proceeds through the formation of an generated acylpyridinium salt followed by trapping with isocyanoacetates and tosylmethyl isocyanide. This transformation has a broad substrate scope with good functional group tolerance (including hindered and less reactive substrates or those containing sensitive functional groups). The versatility of this newly developed reaction is illustrated through its application in the gram-scale production of the FDA-approved prodrug 5-aminolevulinic acid (5-ALA) and the late-stage functionalization of bioactive molecules including estrone, lipoic acid, valproic acid, and probenecid. Additionally, this process features the advantageous recovery and reuse of the base DMAP, underscoring its practical benefits.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acs.joc.4c03166 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Nanocluster-Induced Liquid-like Precursor Formation and Crystallization: In Situ Visualization and 3D Reconstruction.
J Am Chem Soc
March 2025
State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China.
Revealing the crystallization mechanism of inorganic materials modulated by organic molecules has broad implications in biomineralization, crystallography, and materials science. However, directly visualizing the participation of organic molecules in the inorganic materials' crystallization process remains a significant challenge. Here, we introduce carboxyl-functionalized gold nanoclusters (Au NCs) as an alternative to polymers for investigating CaCO crystallization via the transient "Au NCs-induced liquid precursor" phase, similar to "polymer-induced liquid precursor".
View Article and Find Full Text PDF[Integrative transcriptomics-metabolomics approach to identify metabolic pathways regulated by glutamine synthetase activity].
Se Pu
March 2025
CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Glutamine synthetase (GS), the only enzyme responsible for de novo glutamine synthesis, plays a significant role in cancer progression. As an example of the consequences of GS mutations, the R324C variant causes congenital glutamine deficiency, which results in brain abnormalities and neonatal death. However, the influence of GS-deficient mutations on cancer cells remains relatively unexplored.
View Article and Find Full Text PDFRapid and Scalable Synthesis of Oxazoles Directly from Carboxylic Acids.
J Org Chem
March 2025
Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322.
A highly efficient and expedient method for the synthesis of 4,5-disubstituted oxazoles has been developed directly from carboxylic acids, employing a stoichiometric amount of the easy-to-access and stable triflylpyridinium reagent. The overall transformation proceeds through the formation of an generated acylpyridinium salt followed by trapping with isocyanoacetates and tosylmethyl isocyanide. This transformation has a broad substrate scope with good functional group tolerance (including hindered and less reactive substrates or those containing sensitive functional groups).
View Article and Find Full Text PDFThe Pharmacokinetics and Pharmacodynamics of a Hemp-Derived "Full-Spectrum" Oral Cannabinoid Product with a 1:1 Ratio of Cannabidiol to Cannabidiolic Acid and Delta-9-Tetrahydrocannabinol to Delta-9-Tetrahydrocannabinolic Acid: A Double-Blind, Placebo-Controlled, Within-Subjects Human Laboratory Study.
Cannabis Cannabinoid Res
March 2025
Behavioral Pharmacology Research Unit, Department of Psychiatry & Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
To examine the acute pharmacokinetics (PK) and pharmacodynamics (PD) of a patented oral cannabinoid product containing a botanical hemp-derived "full-spectrum" extract with an approximate 1:1 ratio of cannabidiol (CBD) to cannabidiolic acid (CBDA) and delta-9-tetrahydrocannabinol (THC) to delta-9-tetrahydrocannabinolic acid (THCA). Healthy adults ( = 15) ingested soft gels containing 0 (placebo), and approximately 1, 2, and 4 mg/kg of total cannabinoids (combination of CBD, CBDA, THC, THCA, and other minor cannabinoids) in an ascending-dose order in four experimental sessions separated by ≥1 week (the placebo condition occurred randomly within the dose sequence). Mean doses (mg) of primary cannabinoids in the active drug conditions were: 1 mg/kg condition (CBD = 41.
View Article and Find Full Text PDFCmHRE2L-CmACS6 transcriptional cascade negatively regulates waterlogging tolerance in Chrysanthemum.
Mol Hortic
March 2025
State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Landscaping, Ministry of Agriculture and Rural Affairs, Key Laboratory of Biology of Ornamental Plants in East China, National Forestry and Grassland Administration, College of Horticulture, Nanjing Agricultural University, No.1 Weigang, Nanjing, 210095, China.
The role of ethylene as an initial signaling molecule in waterlogging stress is well-established. However, the complex molecular mechanisms underlying ethylene biosynthesis and its functional significance in chrysanthemums under waterlogging conditions have remained unclear. In this study, we observed an increase in the expression of 1-aminocyclopropane-1-carboxylate synthase 6 (CmACS6), which encodes a key enzyme responsible for ethylene biosynthesis, in response to waterlogging.
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!