Crystal structure of bergapten: a photomutagenic and photobiologically active furan­ocoumarin

The title compound, C(12)H(8)O(4), is a furan­ocoumarin [systematic name: 4-meth­oxy-7H-furo[3,2-g]chromen-7-one], which was isolated from the Indian herb T. stictocarpum. The mol­ecule 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, mol­ecules are linked by C—H⋯O hydrogen bonds, forming a three-dimensional framework. There are offset π–π inter­actions present involving the coumarin moieties stacking along the a-axis direction [shortest inter-centroid distance = 3.717 (3) Å].