Scheme 6 Asymmetric synthesis of the protected ABH ring system.
In summary, a connective Pummerer-type cyclisation of
thiols and N-benzyl glyoxamides has been studied and applied
in an asymmetric approach to the protected ABH ring system
of the antitumour and antimicrobial natural product ecteinascidin
597. Studies aimed at completing the synthesis of the natural
product and its analogues are underway.
Scheme 7 Completing the asymmetric synthesis of the ABH ring
We thank the EPSRC and GSK (Industrial CASE award to
L. H. S. S.), University of Medicine and Pharmacy, Ho Chi
Minh City (Scholarship to T. T. N.), and the EPSRC and the
University of Manchester for additional funding.
system.
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This journal is The Royal Society of Chemistry 2011
Chem. Commun., 2011, 47, 10821–10823 10823