title: 9-(2-Hy-droxy-6-oxocyclo-hex-1-en-1-yl)-2,3,4,9-tetra-hydro-1H-xanthen-1-one.
abstract: In the xanthene ring system in the title compound, C19H18O4, the 4H-pyran ring has a maximum deviation of 0.110 (2) Å from planarity and the cyclo-hexene ring exhibits a puckered conformation [puckering parameters Q T = 0.452 (3) Å, θ = 57.0 (4) and ϕ = 131.7 (4)°]. The cyclo-hexene ring attached to the xanthene system adopts an envelope conformation, with the middle of the three methylene C atoms as the flap atom. In the crystal, O-H⋯O and C-H⋯O hydrogen bonds form infinite chains of R 1 (2)(6) ring motifs along [100] with the xanthene groups arranged in an alternating zigzag manner.
authors: Chemistry and Environmental Division, Manchester Metropolitan University, Manchester M1 5GD, England.
authors: Shaaban K
authors: SK
authors: Mohamed
authors: Mehmet
authors: M
authors: Akkurt
authors: Antar A
authors: AA
authors: Abdelhamid
authors: Aamer
authors: A
authors: Saeed
authors: Ulrich
authors: U
authors: Flörke
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