Molecules based on the 5-arylthio-5H-chromenopyridine structure have been studied for a variety of medicinal applications, including liver fibrosis. We have recently found that the C–S linkage can be cleaved with Pt(II) and Au(I), something that was not previously recognized. In this current work, we examine the structure, properties, and reactivity of 5-arylthio-5H-chromenopyridines using spectroscopy, crystallography, reactivity, density functional theory (DFT) calculations, and electrochemistry. We report the crystal structures of 5-arylthio-5H-chromenopyridines, as well as their DFT-calculated structures and electronic structures. The DFT calculations help to explain the electronic properties of these complexes, such as the observation that “soft” metals cleave the C–S bond. We find that the arylthio group is a good leaving group on these molecules due to the stability of the carbocation that is formed, and can be removed via reduction with NaBH₄. Methoxy-substituted chromenopyridines were found to be viable at inhibiting liver fibrosis. These results will help inform the biological studies with these compounds to determine method of action and enhance development of new drug molecules with increased stability and activity based on the 5H-chromenopyridine scaffold.

中文翻译：

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了解具有生物活性的5-芳基硫基-5 H-吡啶并吡啶中C–S键的结构和反应性†

已经研究了基于5-芳硫基-5 H-苯并吡啶结构的分子用于多种医学应用，包括肝纤维化。我们最近发现，C-S键可以被Pt（II）和Au（I）裂解，这是以前没有认识到的。在当前的工作中，我们使用光谱学，晶体学，反应性，密度泛函理论（DFT）计算和电化学检查了5-芳基硫基5 H-铬吡啶并结构，性质和反应性。我们报告了5-芳硫基-5 H的晶体结构-chromenopyridines及其DFT计算的结构和电子结构。DFT计算有助于解释这些络合物的电子性质，例如观察到“软”金属会裂解C–S键。我们发现，由于形成的碳正离子的稳定性，芳硫基是这些分子上的良好离去基团，可以通过用NaBH ₄还原而除去。发现甲氧基取代的色诺吡啶在抑制肝纤维化方面是可行的。这些结果将有助于这些化合物的生物学研究，以确定作用的方法，并基于5 H- chromenopyridine支架增加稳定性和活性增强的新药物分子的开发。