[formula: see text] A convergent construction of the C1-C15 domain of the thyrsiferol-related natural products has been developed. This involved the separate construction of C1-C7 and C8-C15 fragments, their organochromic-mediated coupling, and subsequent reductive closure of the B ring. This synthetic A-B-C ring construct will be useful for the total synthesis of the biologically active polyether squalenoid natural products, as well as their non-natural analogues.