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Updated: Jun 1, 2026
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Ethyl 2-hydr-oxy-5-oxo-4-phenyl-2,3,4,5-tetra-hydro-pyrano[3,2-c]chromene-2-carboxyl-ate
Abstract:
The main structural unit of the title compoud, C(21)H(18)O(6), is a fused three-ring group consisting of coumarin and tetra-hydro-pyrane ring systems. Two C atoms of the tetra-hydro-pyran ring are displaced by 0.295 (3) and -0.360 (2) Å from the mean plane of coumarin ring. The dihedral angle between the phenyl and coumarin rings is 73.94 (3)°. Inter-molecular O-H⋯O hydrogen bonds are present in the crystal structure.
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