Total synthesis of thelephantin O, vialinin A/terrestrin A, and terrestrins B-D.

The first total synthesis of natural, unsymmetrical 2',3'-diacyloxy-p-terphenyls, thelephantin O (1) and terrestrins C and D (2 and 3, respectively), was achieved via a practical route which was also applicable to the synthesis of the symmetrical diesters vialinin A/terrestrin A (4) and terrestrin B (5). Compounds 1-5 exhibited cytotoxicity against cancer cells (HepG2 and Caco2) with IC(50) values of 13.6-26.7 μmol/L.