title: General and efficient syntheses of C(18)-4,8-sphingadienines via S(N)2'-type homoallylic coupling reactions mediated by thioether-stabilized copper reagents.
abstract: The stereoselective syntheses of C(18)-4,8-sphingadienines 3 and 4 as analogues of sphingosine 1 are described. The key step in these syntheses involved a novel S(N)2'-type homoallylic coupling reaction between the corresponding thioether-stabilized allylic copper reagents and the allylic mesylate 7. The thioether-stabilized allylic copper reagents were easily prepared and retained the configuration of their double bond during the coupling reactions, thus overcoming the problem of isomerization which was normally associated with the use of allylic organometallic reagents in such applications.
authors: State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, China.
authors: X Z
authors: XZ
authors: Wang
authors: Y L
authors: YL
authors: Wu
authors: S
authors: S
authors: Jiang
authors: G
authors: G
authors: Singh
mesh_terms: D000498:Allyl Compounds / Q000737:chemistry*; D003300:Copper / Q000737:chemistry; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000138:chemical synthesis*; D013237:Stereoisomerism
chemical_list: D000498:Allyl Compounds; D007202:Indicators and Reagents; D003300:Copper; D013110:Sphingosine