Within the frame of the synthesis of glycine antagonists, a series of novel thieno[2,3- b]pyridinones with substituted phenyl residues in position 5 were synthesised to investigate the importance of the torsion angle between the pyridinone skeleton and the phenyl ring for binding affinity. The parent compound, 4-hydroxy-5-phenylthieno[2,3-b]pyridine-6(7H)-one, and its thienyl analogue, exhibited highest potencies, whereas compounds with ortho-substituted aryl moieties in position 5 showed decreased activities. This seems to be due to unfavourable steric interactions and increased torsion angles between the thieno[2,3- b]pyridinone system and the aryl substituent in position 5. Further evidence is drawn by QSAR studies, which showed an inverse relationship between the size of the ortho-substituent and the binding affinity.
在合成甘氨酸拮抗剂的框架内,合成了一系列在位置5上具有取代苯基残基的新型噻吩[2,3-b]吡啶酮,以研究吡啶酮骨架与苯环之间扭转角对结合亲和力的重要性。母体化合物4-羟基-5-苯基噻吩[2,3-b]吡啶酮-6(7H)-酮及其噻吩基类似物表现出最高的效力,而在位置5具有邻位取代芳基基团的化合物则显示出降低的活性。这似乎是由于不利的立体作用和噻吩[2,3-b]吡啶酮系统与位置5上芳基取代物之间扭转角的增加。进一步的证据来自QSAR研究,显示了邻位取代基的大小与结合亲和力之间的反比关系。