4
Tetrahedron
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In conclusion, murrayaquinone A is synthesized in five
2014; 2014: 540208.
steps starting from commercially available 2,4,5-trimethoxy
benzaldehyde in an overall yield of 45%. The novelty of this
murrayaquinone synthesis is in the use of a Mn(OAc)3 mediated
oxidative radical reaction of a N-benzylaminoquinone derivative
with 2-cyclohexen-1-one for the late-stage indole ring
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1327.
construction. This methodology has the potential to provide rapid
synthetic access to other carbazole-1,4-dione natural products . In
addition, this synthesis will be useful in preparing various
analogs of murrayaquinones with specific substitution patterns,
which will eventually assist in the structure activity relationship
studies to discover lead drug molecules. Further studies along
these lines are currently in progress.
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Chem. Pharm. Bull. 1998; 46: 1948-1949.
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Acknowledgements
60: 12249-12260.
Funding from NIH (R03DE025058-0) and American Heart
Association Greater Southeast Affiliate (AHA0865323E) is
acknowledged. Authors also wish to acknowledge the financial
support by the Collaborative Programmatic Development Grant
from the University of Alabama at Birmingham Comprehensive
Cancer Center.
25. Xu, S; Nguyen, T; Pomilio, I; Vitale, MC; Velu, SE.
Tetrahedron. 2014; 70: 5928-5933.
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Supplementary material
Copies of 1H NMR, 13C NMR spectra of all compounds are
available as Supplementary Material.
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1998; 4115-4120.
Highlights
References and notes
Murrayaquinone A is synthesized in five steps
in an overall yield of 45%.
The synthesis uses of a novel Mn(OAc)3
mediated oxidative radical reaction.
It differs from the existing methods in the late-
stage indole ring construction.
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