Synthesis of 6′- and 7′-(3-furylmethyl) derivatives of endo-1′,2′,3′,4′-tetrahydro-1′,4′-ethano-2′-naphthylethanol with potential activity on Na+, K+-ATPase

Abstract

The 6′- and 7′-(3-furylmethyl) derivatives of endo-1′,2′,3′,4′-tetrahydro-1′,4′-ethano-2′-naphthylethanol 1 have been synthesized as simplified analogues of digitoxigenin. The skeleton was built starting from 3,4-dihydro-1,4-ethanonaphthalen-2(1H)-one 2; the substituents were introduced by a Wittig–Horner reaction followed by a highly stereoselective hydrogenation to form the endo derivative 4 and successive acylation with 3-furoyl chloride to give the intermediates 8a and 8b. Tested compounds showed only moderate activity on the Na⁺, K⁺-ATPase, with IC₅₀ values in the 10^–4 mol dm^–3 range.