8-[(3,3-Dimethyl-oxiran-2-yl)methoxy-meth-yl]-11-hydr-oxy-2-isopropenyl-5-methyl-12-oxo-1,2,3,12-tetra-hydro-pyrano[3
Abstract:
The title compound, commonly known as 14-methoxy-tajixanthone-25-acetate, C(28)H(30)O(8), was isolated from Emericella variecolor. The central xanthone core is approximately planar (r.m.s. deviation = 0.084 Å). The dihydro-pyran ring adopts a distorted half-chair conformation. The oxirane plane is oriented at an angle of 63.3 (2)° with respect to the phenol group. An intra-molecular O-H⋯O hydrogen bond forms an S(6) ring. In the crystal, mol-ecules are linked into a two-dimensional network parallel to the ab plane by weak inter-molecular C-H⋯O hydrogen bonds.
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