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M. Christmann
Scheme 6. Enantioselective synthesis of the decalin 3
Scheme 7. Completion of the synthesis
We were able to halve the catalyst loading to 10 mol% using nitromethane as the solvent and obtained the Diels–Alder adduct 3 in 74% yield
and 86% ee. The ee of 3 was upgraded to >99% by recrystallization of
the corresponding alcohol (19) followed by reoxidation (de Figueiredo
et al. 2007).
Using Danishefsky’s elegant fragment assembly (Lambert and Danishefsky 2006), 4a and 3 were joined to UCS1025A in just four further
steps (Scheme 7), which now allows for a rapid generation of analogs,
which supports our SAR-studies for this important telomerase inhibitor.
M. Christmann
Scheme 6. Enantioselective synthesis of the decalin 3
Scheme 7. Completion of the synthesis
We were able to halve the catalyst loading to 10 mol% using nitromethane as the solvent and obtained the Diels–Alder adduct 3 in 74% yield
and 86% ee. The ee of 3 was upgraded to >99% by recrystallization of
the corresponding alcohol (19) followed by reoxidation (de Figueiredo
et al. 2007).
Using Danishefsky’s elegant fragment assembly (Lambert and Danishefsky 2006), 4a and 3 were joined to UCS1025A in just four further
steps (Scheme 7), which now allows for a rapid generation of analogs,
which supports our SAR-studies for this important telomerase inhibitor.