Homologation of Estrone or Estradiol. Appending a Carbon Substituent Into the 3-hydroxyestra-1,3,5-triene Skeleton

Recent work is reviewed concerning the synthesis of estrone or estradiol homologues, of interest in diagnostics, drug discovery research etc. The survey is limited to reactions where a carbon atom or a carbon chain becomes directly attached to the steroid ring system. Also conversions of non-estranoid starting materials to substituted estrone/estradiol derivatives are discussed. The organization of the review follows steroid numbering.