Synthesis of Coleon C

Using a synthetic route elaborated with closely related models1 and previously proven effective in a synthesis of coleon Utri-0-methyl ether2, we have recently completed the preparation of coleon C as the tri- and tetra-0-methyl ethers, 13a and 13b respcctively. Coleon C was described by Eugster and co-workers3 who also established the absolute stereochemistry at C.10 and C.154.