X-ray study of weak interactions in two flavonoids

Bulletin of materials science

Vivek K Gupta²  Goutam Brahmachari³  Arindam Gangopadhyay³  Sadhan Mondal³  Deepak Sharma¹ 

[1] Post Graduate Department of Physics, University of Jammu, Jammu Tawi 180 006, India$$Post Graduate Department of Physics, University of Jammu, Jammu Tawi 180 006, IndiaPost Graduate Department of Physics, University of Jammu, Jammu Tawi 180 006, India$$;Post Graduate Department of Physics, University of Jammu, Jammu Tawi 180 006, India$$Department of Chemistry, Visva Bharati University, Santiniketan 731 235, India$$Post Graduate Department of Physics, University of Jammu, Jammu Tawi 180 006, IndiaPost Graduate Department of Physics, University of Jammu, Jammu Tawi 180 006, India$$Department of Chemistry, Visva Bharati University, Santiniketan 731 235, India$$Department of Chemistry, Visva Bharati University, Santiniketan 731 235, IndiaPost Graduate Department of Physics, University of Jammu, Jammu Tawi 180 006, India$$Department of Chemistry, Visva Bharati University, Santiniketan 731 235, India$$;Department of Chemistry, Visva Bharati University, Santiniketan 731 235, India$$Department of Chemistry, Visva Bharati University, Santiniketan 731 235, IndiaDepartment of Chemistry, Visva Bharati University, Santiniketan 731 235, India$$

关键词: Flavonoid;    direct methods;    Câ€�?�H$ldots pi$ hydrogen bond;    𝜋–ðœ�?? interaction;    gauche;    benzopyran.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

X-ray diffraction studies were carried out on single crystals of two flavonoids, viz. 5-hydroxy-6,7,4â€�?-trimethoxyflavone, C₁₈H₁₆O₆, (I) and 5-hydroxy-3,7,4â€�?-trimethoxyflavone, C₁₈H₁₆O₆, (II). Crystal structures of both the flavonoids were solved by direct methods and refined by full-matrix least-squares procedures. In both the molecules, the benzopyran moiety is planar. The dihedral angle between the phenyl ring and the benzopyran portion is 5.50(4)° in (I) and 29.11(5)° in (II). In (I), the crystal packing is influenced by Oâ€�?�H…O hydrogen bonds, and weak Câ€�?�H…O and $pi ldots pi$ interactions whereas in (II) the crystal structure is stabilized by the presence of four intermolecular short contacts of the type Câ€�?�H…O. There is also one Câ€�?�H$ldots pi$ hydrogen bond with Hâ€�? centroid distance of < 2.7 Ã�?. The molecules are further stabilized by 𝜋–ðœ�?? interactions.

【 授权许可】

Unknown