Bauri A K, Foro Sabine, Rahman A F M M
Bio-Organic Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India.
Institute of Materials Science, Darmstadt University of Technology, Alarich-Weiss-Strasse 2, D-64287 Darmstadt, Germany.
Acta Crystallogr E Crystallogr Commun. 2017 Apr 28;73(Pt 5):774-776. doi: 10.1107/S2056989017006132. eCollection 2017 May 1.
The title compound, CHBrO [systematic name: -(9,10)-3,9-dibromo-10-methoxy-8,8-dimethyl-9,10-dihydropyrano[2,3-]chromen-2(8)-one], is a pyran-ocoumarin derivative formed by the bromination of seselin, which is a naturally occurring angular pyran-ocoumarin isolated from the Indian herb . In the mol-ecule, the benzo-pyran ring system is essentially planar, with a maximum deviation of 0.044 (2) Å for the O atom. The di-hydro-pyran ring is in a half-chair conformation and the four essentially planar atoms of this ring form a dihedral angle of 4.6 (2)° with the benzo-pyran ring system. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, forming chains propagating along [010]. In addition, π-π stacking inter-actions, with centroid-centroid distances of 3.902 (2) and 3.908 (2) Å, link the hydrogen-bonded chains into layers parallel to (001).
标题化合物CHBrO [系统名称：-(9,10)-3,9-二溴-10-甲氧基-8,8-二甲基-9,10-二氢吡喃并[2,3-]色烯-2(8)-酮]是一种吡喃并香豆素衍生物，由蛇床子素溴化形成，蛇床子素是从印度草药中分离出的一种天然存在的角型吡喃并香豆素。在分子中，苯并吡喃环系基本呈平面状，O原子的最大偏差为0.044 (2) Å。二氢吡喃环呈半椅构象，该环的四个基本呈平面状的原子与苯并吡喃环系形成4.6 (2)°的二面角。在晶体中，分子通过弱C-H⋯O氢键相连，形成沿[010]方向延伸的链。此外，质心间距为3.902 (2) 和3.908 (2) Å的π-π堆积相互作用将氢键链连接成平行于(001)的层。
