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Total synthesis of (+)-psymberin (irciniastatin A): catalytic reagent control as the strategic cornerstone.

ABSTRACT: An effective total synthesis of the marine sponge cytotoxin (+)-psymberin [irciniastatin A (1)] has been achieved. Highlights of the strategy include a Diels-Alder reaction between a bis-siloxy diene and an allene to construct the aromatic ring, a boron-mediated aldol reaction to elaborate the C(15-17) all syn stereotriad, catalytic reagent control to set the C(8, 9, 11 and 13) stereogenic centers of the tetrahydropyran core, and a late-stage Curtius rearrangement to install the sensitive N,O-aminal moiety. The synthesis proceeds with a longest linear sequence of 21 steps from commercially available 2,2-dimethyl-1,3-propanediol.

SUBMITTER: Smith AB

PROVIDER: S-EPMC2750869 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature

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Total synthesis of (+)-psymberin (irciniastatin A): catalytic reagent control as the strategic cornerstone.

Smith Amos B AB Jurica Jon A JA Walsh Shawn P SP

Organic letters 20081201 24

An effective total synthesis of the marine sponge cytotoxin (+)-psymberin [irciniastatin A (1)] has been achieved. Highlights of the strategy include a Diels-Alder reaction between a bis-siloxy diene and an allene to construct the aromatic ring, a boron-mediated aldol reaction to elaborate the C(15-17) all syn stereotriad, catalytic reagent control to set the C(8, 9, 11 and 13) stereogenic centers of the tetrahydropyran core, and a late-stage Curtius rearrangement to install the sensitive N,O-am ...[more]

PMID: 19072197

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