title: 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.
abstract: Halisphingosines 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.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0358, USA. tmolinski@ucsd.edu
authors.forename: Tadeusz F
authors.initials: TF
authors.lastname: Molinski
authors.forename: Renata
authors.initials: R
authors.lastname: Biegelmeyer
authors.forename: E Paige
authors.initials: EP
authors.lastname: Stout
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
authors.forename: Mario L C
authors.initials: ML
authors.lastname: Frota
authors.forename: Amelia T
authors.initials: AT
authors.lastname: Henriques
mesh_terms: D000818:Animals; D001938:Brazil; D002942:Circular Dichroism; D047129:Haliclona / Q000737:chemistry*; D008386:Marine Biology; D015394:Molecular Structure; D056910:Republic of Korea; D013107:Sphingolipids / Q000737:chemistry / Q000302:isolation & purification*; D013237:Stereoisomerism
chemical_list: D013107:Sphingolipids; C581269:halisphingosine A; C581270:halisphingosine B