Synthesis of the cyclobutylfuran sector of providencin via zirconium-mediated oxygen abstraction from a furanoside.

A portion of the macrocyclic cembrenoid diterpene providencin possessing conjoined cyclobutane and furancarboxylate units was synthesized from D-glucose using deoxygenative ring contraction methodology to construct the tetrasubstituted cyclobutane and a Knoevenagel condensation of glyceraldehyde to fabricate the trisubstituted furan.