Crystal structure of bergapten: a photomutagenic and photobiologically active furan-ocoumarin

Acta Crystallogr E Crystallogr Commun. 2016 Jul 22;72(Pt 8):1194-6. doi: 10.1107/S2056989016011221. eCollection 2016 Aug 1.

Abstract

The title compound, C12H8O4, is a furan-ocoumarin [systematic name: 4-meth-oxy-7H-furo[3,2-g]chromen-7-one], which was isolated from the Indian herb T. stictocarpum. The mol-ecule is almost planar with an r.m.s. deviation of 0.024 Å for the hetero atoms of the fused-ring system. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming a three-dimensional framework. There are offset π-π inter-actions present involving the coumarin moieties stacking along the a-axis direction [shortest inter-centroid distance = 3.717 (3) Å].

Keywords: C—H⋯O hydrogen bonds; T. sticto­carpum; bergapten; crystal structure; furan­ocoumarin; photobiological activity; psoralen; π–π inter­actions.