Vl. Novikov et al., SYNTHESIS OF SHIKALKIN AND CERTAIN RELATED-COMPOUNDS, Bulletin of the Russian Academy of Sciences, Division of Chemical Sciences, 41(8), 1992, pp. 1485-1494
A successful total synthesis of a biologically active pigment from pla
nts of the Boraginaceae family was carried out with naphthazarine as t
he starting material, and using the 1,4,5,8-tetramethoxynaphthalene, t
he corresponding 2-vinyl derivative and its epoxide or a cyclopropane
adduct with diazoacetic ester at the key stages. In the course of deve
loping the scheme of the synthesis of shikalkin, its three analogs wer
e obtained, differing in the nature of the monoterpenoid side chain.