Synthetic studies on Sch 202596, an antagonist of the galanin receptor subtype GalR1: an efficient synthesis of (±)-geodin, the spirocoumaranone part of Sch 202596

An efficient and facile synthesis of (±)-geodin ] corresponding to the spirocoumaranone part of Sch 202596 () was accomplished in a convergent manner. The synthetic method features (i) a coupling reaction of the aryl aldehyde with the aryl lithium generated in situ from the aryl bromide to deliver the highly substituted diaryl methanol (+→) and ii) oxidative spirocyclization reaction of the benzophenone to construct the requisite spirocoumaranone skeleton [] as the key steps. The aromatic segments and were prepared from commercially available methyl 3,5-dihydroxybenzoate () and 5-methylresorcinol (), respectively.