Novel ring chemistry of vitamin B6 with singlet oxygen and an activated ene: isolated products and identified intermediates suggesting an operable [3 + 2] cycloaddition
作者:David Samuel、Kirsten Norrell、David G. Hilmey
DOI:10.1039/c2ob26067k
日期:——
in aqueous solution at neutral pH resulted in oxidation at the 2- and 6-positions of the pyridine ring and unprecedented ring contraction. Kinetic and low temperature studies provided observable intermediates by NMR spectroscopy. In addition, novel cycloaddition between pyridoxine and N-methylmaleimide, without N-alkylation and in water, suggest a common [3 + 2] cycloaddition with the 3-hydroxypyridine
吡ox醇与1 O 2的水溶液在中性pH下反应,导致吡啶环的2位和6位氧化,并发生空前的环收缩。动力学和低温研究通过NMR光谱提供了可观察到的中间体。另外,新颖的环加成之间吡ido醇 和 N-甲基马来酰亚胺,没有N-烷基化和水,建议与3-羟基吡啶环共同的[3 + 2]环加成。