| abstract |
Multiple novel reaction schemes, novel process steps and novel intermediates are provided for the synthesis of epoxymexrenone and other compounds of Formula I n n n wherein: n —A—A— represents the group —CHR 4 —CHR 5 — or —CR 4 ═CR 5 — n R 3 , R 4 and R 5 are independently selected from the group consisting of hydrogen, halo, hydroxy, lower alkyl, lower alkoxy, hydroxyalkyl, alkoxyalkyl, hydroxycarbonyl, cyano, aryloxy, n R 1 represents an alpha-oriented lower alkoxycarbonyl or hydroxyalkyl radical, n —B—B— represents the group —CHR 6 —CHR 7 — or an alpha- or beta-oriented group: n n n where R 6 and R 7 are independently selected from the group consisting of hydrogen, halo, lower alkoxy, acyl, hydroxyalkyl, alkoxyalkyl, hydroxycarbonyl, alkyl, alkoxycarbonyl, acyloxyalkyl, cyano, aryloxy, and n R 8 and R 9 are independently selected from the group consisting of hydrogen, halo, lower alkoxy, acyl, hydroxyalkyl, alkoxyalkyl, hydroxycarbonyl, alkyl, alkoxycarbonyl, acyloxyalkyl, cyano, aryloxy, or R 8 and R 9 together comprise a carbocyclic or heterocyclic ring structure, or R 8 or R 9 together with R 6 or R 7 comprise a carbocyclic or heterocyclic ring structure fused to the pentacyclic D ring. |