The preparation of estrone derived benzothieno- and benzofurano fused steroids is described. Keystep is an intramolecular thienyl(/furyl)ene-yne cyclization of 16-ethynyl-17-heterarylestra-1,3,5(10),16-tetraenes. The cyclization was carried out under Pt as well as under Ru catalysis. (c) 2005 Elsevier Inc. All rights reserved.
The preparation of estrone derived benzothieno- and benzofurano fused steroids is described. Keystep is an intramolecular thienyl(/furyl)ene-yne cyclization of 16-ethynyl-17-heterarylestra-1,3,5(10),16-tetraenes. The cyclization was carried out under Pt as well as under Ru catalysis. (c) 2005 Elsevier Inc. All rights reserved.
The preparation of estrone derived benzothieno- and benzofurano fused steroids is described. Keystep is an intramolecular thienyl(/furyl)ene-yne cyclization of 16-ethynyl-17-heterarylestra-1,3,5(10),16-tetraenes. The cyclization was carried out under Pt as well as under Ru catalysis. (c) 2005 Elsevier Inc. All rights reserved.