Organic Letters
Letter
(14) Phutdhawong, W.; Pyne, S. G.; Baramee, A.; Buddhasukh, D.;
Skelton, B. W.; White, A. H. Tetrahedron Lett. 2002, 43, 6047.
(15) This hypothesis is supported by the isolation of a side product
from the reaction which has tentatively been assigned as the following
phenol tautomer of the result of a base-mediated elimination of tetraol 2:
has been shown to have an increased antiproliferative effect
compared with grandifloracin on PANC-1 and HT-29 (human
colon cancer) cells, both in nutrient-rich (10% fetal bovine
serum) and in nutrient-deprived conditions (0.5% fetal bovine
serum).16 This indicates that there is an incentive to develop
further grandifloracin analogues for the study and treatment of
pancreatic cancer.
ASSOCIATED CONTENT
* Supporting Information
■
S
Detailed experimental procedures, IR, 1H, and 13C NMR spectra
for all new compounds. The Supporting Information is available
(16) Ali Khan, M.; Wood, P. J.; Lamb-Guhren, N. M.; Caggiano, L.;
Kociok-Kohn, G.; Tosh, D.; Lewis, S. E. Bioorg. Med. Chem. Lett. 2014,
̈
24, 2815.
AUTHOR INFORMATION
Corresponding Author
■
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
The authors wish to thank NSF (1265591), Amgen, and Caltech
for financial support. M.B. thanks the Drug Research Academy
and the Danish Cancer Society for financial support. D.C.D.
(Caltech) thanks the National Science Foundation for financial
support (Predoctoral Research Fellowship, No. DGE-1144469).
L.C. (Caltech) is grateful to the Arthur R. Adams SURF
Endowment. The Caltech Center for Catalysis and Chemical
Synthesis (C3S) and especially Dr. Scott Virgil (Caltech) are
acknowledged for help with chiral separation. Dr. Michael K.
Takase (Caltech) is acknowledged for X-ray crystallographic
structural determination.
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