synthesis of leucascandrolide a via a spontaneous macrolactolization j. am. chem. soc. 2002, 124,...
DESCRIPTION
About Leucascandrolide A Its is a highly bioactive marine macrolide isolated from new genus of calcerous sponges Leucascandra caveolata. It displays potent cytotoxicity against KB and P388 tumor cell lines ( IC ng/ml and 0.25 μg/mL respectively), and it also a strong inhibitor of animal-pathogenic yeast candida albicans. Structural Features of Leucascandrolide A It possess a 14 membered lactone It includes dioxotricyclic core It is highly unsaturated and contains oxazole in its side chain. 2TRANSCRIPT
Synthesis of Leucascandrolide A via a Spontaneous Macrolactolization
J. Am. Chem. Soc. 2002, 124, 13670-13671
Presented by Vijayarajan Devannah3/19/2013
Ying Wang, Jelena Janjic, Sergey A. Kozmin
About Professor Sergey A. Kozmin Education and Professional• 1991-1993 Undergraduate Research Assistant with Professor Irina P. Beletskaya Lomonosov Moscow State University, Moscow, Russia•1993-1998 Graduate Research Assistant with Professor Viresh H. RawalUniversity of• Chicago, Chicago, Illinois•1998-2000 Postdoctoral Associate with Professor Amos B. Smith, III University of Pennsylvania, Philadelphia, Pennsylvania•2000-2006 Assistant Professor, University of Chicago•2006-2011 Associate Professor, University of Chicago•2011-present Professor, University of ChicagoNotable Awards•2003 Alfred P. Sloan Fellow•2004 American Cancer Society Research Scholar•2004 Amgen Young Investigator’s Award•2004 Camille Dreyfus Teacher-Scholar Award•2005 NSF CAREER Award•2005 GlaxoSmithKline Chemistry Research Scholar 2
About Leucascandrolide A
•Its is a highly bioactive marine macrolide isolated from new genus of calcerous sponges Leucascandra caveolata.•It displays potent cytotoxicity against KB and P388 tumor cell lines ( IC50 50 ng/ml and 0.25 μg/mL respectively), and it also a strong inhibitor of animal-pathogenic yeast candida albicans. Structural Features of Leucascandrolide A•It possess a 14 membered lactone •It includes dioxotricyclic core•It is highly unsaturated and contains oxazole in its side chain.
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Retrosynthesis
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Synthesis of C1-C15 Fragment
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Scheme 2
Scheme 3
Continues……
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Scheme 4
Scheme 5
Formation of crucial Macrocycle
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Scheme 5
Synthesis of Oxazole side chain and completion of the target Leucascandrolide
A
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Scheme 6
Conclusion• Racemic Leucascandrolide A was synthesized in longest linear
sequence of 18 steps from commercially available precursors. 500 MHz 1H NMR and 125 MHz 13C NMR spectra of synthetic Leucascandrolide A was in excellent agreement with those reported in literature.
• Total yield is 2%
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Thank You
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