Synthesis of pachastrissamine from phytosphingosine: a comparison of cyclic sulfate vs an epoxide intermediate in cyclization.
[reaction: see text] The syntheses of the cytotoxic natural product pachastrissamine and its unnatural 4-epi-congener were accomplished starting from a natural phytosphingosine. The relatively unstrained cyclic sulfate intermediate smoothly underwent the 5-endo cyclization to yield the 2,3,4-trisubstituted tetrahydrofuran ring system of pachastrissamine. The corresponding epoxy alcohol afforded the 4-epi-congener via a tosylate-mediated double inversion process.
Lee
Taeho
T
College of Pharmacy, Seoul National University, San 56-1, Shilim, Kwanak, Seoul 151-742, Korea.
Lee
Sukjin
S
Kwak
Young Shin
YS
Kim
Deukjoon
D
Kim
Sanghee
S
D003500:Cyclization; D004852:Epoxy Compounds / Q000737:chemistry*; D008956:Models, Chemical; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D013431:Sulfates / Q000737:chemistry*
D004852:Epoxy Compounds; D013431:Sulfates; C468594:pachastrissamine; C012491:phytosphingosine; D013110:Sphingosine