Total synthesis of the supposed structure of (-)-sclerophytin A and an improved route to (-)-7-deacetoxyalcyonin acetate.
[reaction: see text]Stereoselective acid-catalyzed rearrangement of 15-->16 is the central step in total syntheses of (-)-7-deacetoxyalcyonin acetate (1) and the compound with the alleged structure of sclerophytin A (2). Since tetracyclic diether 2 is not identical to sclerophytin A, the structure of this antineoplastic marine diterpene must be revised. The conversion of 15-->16 demonstrates for the first time that tetrahydrofurans containing (Z)-1-methylalkenyl side chains can be prepared by Prins-pinacol rearrangements.
Overman
L E
LE
Department of Chemistry, University of California, Irvine 92697-2025, USA. leoverma@uci.edu
Pennington
L D
LD
D000085:Acetates / Q000138:chemical synthesis*; D017607:Aluminum Compounds; D001952:Bridged-Ring Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D004224:Diterpenes / Q000138:chemical synthesis*; D005663:Furans / Q000138:chemical synthesis* / Q000737:chemistry; D007202:Indicators and Reagents; D018020:Lithium Compounds; D008968:Molecular Conformation; D013237:Stereoisomerism
C414388:7-deacetoxyalcyonin acetate; D000085:Acetates; D017607:Aluminum Compounds; D001952:Bridged-Ring Compounds; D004224:Diterpenes; D005663:Furans; D007202:Indicators and Reagents; D018020:Lithium Compounds; C412667:sclerophytin A; C042073:lithium aluminum hydride