10.1039/b508972g
The research focuses on the development of a novel and efficient method for generating o-quinone methide intermediates, which are crucial in the biomimetic synthesis of complex benzopyran derived natural products, specifically (±)-lucidene and (±)-alboatrin. The study provides experimental evidence supporting the hypothesis that the biogenesis of these natural products may involve a hetero Diels–Alder cycloaddition between an o-quinone methide intermediate and a simple or activated tri-substituted olefin. The researchers successfully synthesized (±)-lucidene and (±)-alboatrin using this new method, which involves the preparation of o-quinone methide precursors 6a and 6b. The experiments utilized various reactants, including 2-hydroxybenzyl alcohol, acetyl chloride, and different dienophiles, and were conducted under controlled conditions such as specific temperatures and the use of inert atmospheres. Analytical techniques employed in the study included NMR spectroscopy, mass spectrometry, infrared spectroscopy, and X-ray crystallography, which were used to characterize the intermediates and final products, confirming their structures and evaluating the efficiency of the newly developed synthetic method.
10.1021/jm801016j
The research focuses on the synthesis and structure-activity relationships of long-acting β2 adrenergic receptor agonists that incorporate aryl sulfonamide groups. These compounds are designed for the treatment of asthma and chronic obstructive pulmonary disease (COPD). The study involves the preparation of a series of saligenin alkoxyalkylphenylsulfonamide β2 adrenoceptor agonists through a series of chemical reactions, including alkylation, Sonogashira coupling, hydrogenation, and deprotection. Saligenin was used as a key starting material for synthesizing β2 adrenergic receptor agonists. The researchers assessed the potency, selectivity, onset, and duration of action of these compounds in vitro using isolated superfused guinea pig trachea and human bronchus. They also examined the oral bioavailability and in vivo duration of action in animal models. The research identified sulfonamide 29b as the most promising candidate, which exhibited a favorable profile in terms of potency, selectivity, and duration of action. The study proposed a binding mode for 29b to the β2-receptor and discussed the potential of this compound for once-daily dosing as a third-generation product for asthma treatment. The experiments involved the use of various analytical techniques such as high-resolution mass spectrometry (HRMS), nuclear magnetic resonance (NMR) spectroscopy, and high-performance liquid chromatography (HPLC) for compound characterization and purity assessment.
10.1021/jo062416m
The research presents a novel synthetic methodology for constructing three distinct carbocyclic frameworks—dupreziananes, sterpuranes, and polyquinanes—using cycloaddition reactions of cyclohexa-2,4-dienones with acyclic dienes, followed by ring-closing metathesis and photochemical transformations. Key reactants included o-hydroxymethyl phenols and various acyclic dienes, with the synthesis involving the oxidation of phenolic precursors to generate cyclohexa-2,4-dienones. The experiments utilized Grubbs catalyst for ring-closing metathesis and employed photochemical reactions to facilitate acyl shifts, yielding complex tricyclic structures. Analyses were conducted using NMR spectroscopy, IR spectroscopy, and mass spectrometry to confirm the structures and purity of the synthesized compounds, alongside single-crystal X-ray diffraction for structural elucidation.
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