This study of 3‐(5‐phenyl‐1,3,4‐oxadiazol‐2‐yl)‐2H‐chromen‐2‐one, C₁₇H₁₀N₂O₃, 1, and 3‐[5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazol‐2‐yl]‐2H‐chromen‐2‐one, C₁₆H₉N₃O₃, 2, was performed on the assumption of the potential anticancer activity of the compounds. Three polymorphic structures for 1 and two polymorphic structures for 2 have been studied thoroughly. The strongest intermolecular interaction is stacking of the `head‐to‐head' type in all the studied crystals. The polymorphic structures of 1 differ with respect to the intermolecular interactions between stacked columns. Two of the polymorphs have a columnar or double columnar type of crystal organization, while the third polymorphic structure can be classified as columnar‐layered. The difference between the two structures of 2 is less pronounced. Both crystals can be considered as having very similar arrangements of neighbouring columns. The formation of polymorphic modifications is caused by a subtle balance of very weak intermolecular interactions and packing differences can be identified only using an analysis based on a study of the pairwise interaction energies.

中文翻译：

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3-（5-苯基-1,3,4-恶二唑-2-基）-和3- [5-（吡啶-4-基）-1,3,4-恶二唑-2-基] -2H的多态性-chromen-2-ones。

本研究3-（5-苯基-1,3,4-恶二唑-2-基）-2- ħ -色烯-2-酮，C ₁₇ ħ ₁₀ Ñ ₂ ö ₃，1，和3- [5-（吡啶-4-基）-1,3,4-恶二唑-2-基] -2- ħ -色烯-2-酮，C ₁₆ H ^ ₉ ñ ₃ ö ₃，2，对所潜在的抗癌活性的假设下执行的化合物。三个多态性结构1和两个多态型结构2已经进行了彻底的研究。最强的分子间相互作用是所有研究晶体的“头对头”堆积。的多晶结构1相对于堆叠的列之间的分子间相互作用不同。两个多晶型物具有柱状或双柱状晶体结构，而第三个多晶型结构可分类为柱状层状。2的两个结构之间的差异不太明显。两种晶体都可以视为相邻列的排列非常相似。多态性修饰的形成是由非常弱的分子间相互作用的微妙平衡引起的，只有通过基于成对相互作用能的分析才能确定堆积差异。