Simple Routes to Sarkomycin

Abstract

Two synthetic routes to sarkomycin (6) are demonstrated. The first involves a 3-carbon annelation to form the spirocyclopentenone (2) followed by regiospecific γ-alkylation and subsequent manipulation of the side chain in 15 to give the sarkomycin ester adduct 18. The second route employs the itaconate-anthracene adduct 20 as the C-5 synthon in a tandem Michael addition-Dieckmann condensation between the anion derived from 20 and methyl acrylate. The reaction furnishes the diester 22, which, upon selective decarboxylation, gives rise to the sarkomycin precursors 18 and 23 (1:3). Flash vacuum pyrolysis of either isomer 18 or 23 yields (±)-sarkomycin ester 7 which is then hydrolyzed to the acid 6. © 1984, American Chemical Society. All rights reserved.