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Updated: Jun 1, 2026
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
1-Hydr-oxy-3-(3-methyl-but-2-en-yloxy)xanthone
Abstract:
In the title compound, C(18)H(16)O(4), a monoprenylated xanthone, the xanthone skeleton exhibits an essentially planar conformation (r.m.s. deviation 0.0072 Å) and the isoprenyl side chain remains approximately in the mean plane of the xanthone unit, making a dihedral angle of 4.5 (2)°. The hydroxyl group forms an intra-molecular O-H⋯O hydrogen bond. Moreover, there is a weak inter-molecular C-H⋯O inter-action between a ring C atom and the xanthene O atom. In the crystal structure, there are no inter-molecular hydrogen bonds and the crystallographic packing is governed by van der Waals forces, leading to an arrangement in which the mol-ecules assemble with their planes parallel to each other, having a separation of 3.6 (3) Å.
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