np300744y_si_001.pdf (1.62 MB)
Halisphingosines A and B, Modified Sphingoid Bases from Haliclona tubifera. Assignment of Configuration by Circular Dichroism and van’t Hoff’s Principle of Optical Superposition
journal contribution
posted on 2013-03-22, 00:00 authored by Tadeusz F. Molinski, Renata Biegelmeyer, E. Paige Stout, Xiao Wang, Mario L. C. Frota, Amelia T. HenriquesHalisphingosines A (1) and B (2), modified
long-chain sphingoid bases, from the marine sponge Haliclona
tubifera collected in Brazil, were characterized after conversion
to their N-Boc derivatives. The 2R,3R,6R configuration of halisphingosine
A, a compound first reported from Haliclona sp. from
South Korea, was confirmed using a novel CD approach: deconvolution
of exciton coupling from mono- and trinaphthoyl derivatives obtained
by derivatization of the natural product. The sensitive CD deconvolution
method, applicable to submilligram samples, simultaneously predicted
the relative and absolute configuration of three stereocenters in
halisphingosine A with precision and accuracy. Halisphingosine B was
assigned by correlation to halisphingosine A.