This paper describes the details of our synthetic studies on the marine steroidal alkaloids cortistatins A and J. The key features of our strategy include (i) an efficient Knoevenagel/electrocyclic strategy to couple the diketone and the CD-ring fragment, (ii) a chemoselective radical cyclization to construct the oxabicyclo[3.2.1]octene B-ring system, (iii) a highly stereocontrolled installation of the isoquinoline unit, and (iv) a late-stage functionalization of the A-ring.
Reappraisal of the diastereoselectivity of intramolecular Diels–Alder reactions of some o-quinodimethanes generated by benzocyclobutene thermolysis: some complementary results and an improvement
作者:Marc Port、Robert Lett
DOI:10.1016/j.tetlet.2006.04.128
日期:2006.7
In a synthetic approach to 19-nor steroids and in order to compare the diastereoselectivities observed for the intramolecular Diels–Alder reactions of o-quinodimethanes generated either from 1 or 2, the thermolysis of benzocyclobutenes such as 2 was reexamined. The IMDA diastereoselectivity was highly dependent on the nature of the protective group of the hydroxyl substituent at the unique chiral stereocentre
This paper describes the details of our synthetic studies on the marine steroidal alkaloids cortistatins A and J. The key features of our strategy include (i) an efficient Knoevenagel/electrocyclic strategy to couple the diketone and the CD-ring fragment, (ii) a chemoselective radical cyclization to construct the oxabicyclo[3.2.1]octene B-ring system, (iii) a highly stereocontrolled installation of the isoquinoline unit, and (iv) a late-stage functionalization of the A-ring.
A novel approach to optically active trans-benzoperhydroindan (2,3,3a,3b,4,5-hexahydro-1 H-benz[e]indene)
Optically active trans-benzoperhydroindan 1 and its enantiomer have been synthesised by thermolysis of the optically active alkenic benzocyclobutene 10 as a key process.