Synthesis of the [5-7-6] tricyclic core of guanacastepene A via an intramolecular Mukaiyama aldol reaction.

[reaction: see text] A synthesis of the tricyclic [5-7-6] skeleton of guanacastepene A is described. The six-membered ring of guanacastepene A was constructed by a Diels-Alder reaction. After several functional group transformations, it was coupled to beta-iodocyclopentenone. Lithium dimethylcuprate conjugate addition followed by an intramolecular Mukaiyama aldol reaction furnished the desired [5-7-6] tricyclic ring system.

[1]  P. Magnus,et al.  Synthesis of the hydroazulene portion of guanacastepene A using a [2.3]sigmatropic sulfoxide rearrangement: observations on silyl enol ether electrophilic chemistry for the introduction of the C-13 hydroxyl group , 2002 .

[2]  Daesung Lee,et al.  Synthesis of the 5-7-6 core of guanacastepenes. Construction of C8 quaternary carbon via the inversion of stereochemistry. , 2002, Organic letters.

[3]  F. Boyer,et al.  Synthesis of a highly functionalized tricyclic ring system related to guanacastepene via a tandem ring-closing metathesis reaction , 2002 .

[4]  G. Mehta,et al.  Towards a total synthesis of guanacastepene A: construction of fully functionalized AB and BC ring segments , 2002 .

[5]  M. Tius,et al.  Synthesis of the hydroazulene portion of guanacastepene A from the cyclopentannelation reaction. , 2002, Organic letters.

[6]  B. Patel,et al.  Tetrabutylammonium tribromide (TBATB) as an efficient generator of HBr for an efficient chemoselective reagent for acetalization of carbonyl compounds. , 2002, The Journal of organic chemistry.

[7]  Derek S. Tan,et al.  Synthesis of the functionalized tricyclic skeleton of guanacastepene A: a tandem epoxide-opening beta-elimination/knoevenagel cyclization. , 2002, Angewandte Chemie.

[8]  Derek S. Tan,et al.  A stereoselective route to guanacastepene A through a surprising epoxidation. , 2002, Angewandte Chemie.

[9]  Daesung Lee,et al.  Progress towards the total synthesis of guanacastepene A. Approaches to the construction of quaternary carbons and the 5-7-6 tricyclic carbon skeleton , 2002 .

[10]  W. Shipe,et al.  A convergent synthesis of the tricyclic architecture of the guanacastepenes featuring a selective ring fragmentation. , 2002, Organic letters.

[11]  G. Mehta,et al.  Studies toward the total synthesis of diterpene antibiotic guanacastepene A: construction of the hydroazulenic core. , 2002, Organic letters.

[12]  D. Trauner,et al.  A practical variant of the Claisen-Eschenmoser rearrangement: Synthesis of unsaturated morpholine amides , 2002 .

[13]  B. Snider,et al.  A novel extension of the Stork–Jung vinylsilane Robinson annelation procedure for the introduction of the cyclohexene of guanacastepene , 2001 .

[14]  J. Clardy,et al.  The guanacastepenes: a highly diverse family of secondary metabolites produced by an endophytic fungus. , 2001, Journal of the American Chemical Society.

[15]  Derek S. Tan,et al.  Remarkable stereoselectivity in the alkylation of a hydroazulenone: progress towards the total synthesis of guanacastepene , 2001 .

[16]  M. Waring,et al.  Stereoselective synthesis of the bicyclo[5.3.0]decane portion of the diterpene antibiotic guanacastepene using a pyrylium-ylide [5+2] cycloaddition reaction , 2001 .

[17]  S. Danishefsky,et al.  A four-step synthesis of the hydroazulene core of guanacastepene. , 2001, Organic letters.

[18]  B. Snider,et al.  Synthesis of the hydroazulene ring system of guanacastepene. , 2001, Organic letters.

[19]  J. Clardy,et al.  Biological activity of guanacastepene, a novel diterpenoid antibiotic produced by an unidentified fungus CR115. , 2000, The Journal of antibiotics.

[20]  Sean F. Brady,et al.  Guanacastepene, a fungal-derived diterpene antibiotic with a new carbon skeleton , 2000 .

[21]  D. Hart,et al.  A Diels-Alder approach to Stemona alkaloids: total synthesis of stenine , 1993 .

[22]  H. Neu,et al.  The Crisis in Antibiotic Resistance , 1992, Science.

[23]  G. Kokotos A Convenient One-Pot Conversion of N-Protected Amino Acids and Peptides into Alcohols , 1990 .

[24]  M. P. Yeh,et al.  Synthesis and reactivity toward acyl chlorides and enones of the new highly functionalized copper reagents RCu(CN)ZnI , 1988 .

[25]  J. A. Marshall,et al.  Synthesis of 7(8)-desoxyasperdiol. A precursor of the cembranoid asperdiol , 1986 .

[26]  Amos B. Smith,et al.  Preparation, stereochemistry, and nuclear magnetic resonance spectroscopy of 4-hydroxy(acetoxy)bicyclo[5.1.0]octanes. Synthesis of (-)- and (.+-.)-8,8-dimethylbicyclo[5.1.0]oct-2-en-4-one , 1982 .

[27]  C. K. Lau,et al.  Synthesis of -chloro, -bromo, and -iodo a,-unsaturated ketones , 1982 .

[28]  B. Harrison,et al.  Studies on the synthesis of vitamin B12. 2. Synthesis of the "southern" half. , 1976, Journal of the American Chemical Society.

[29]  E. S. Binkley,et al.  Regiospecific alkylation of enolate ions in liquid ammonia-tetrahydrofuran , 1975 .

[30]  T. Mukaiyama,et al.  NEW SYNTHESES OF -ALKOXY KETONES AND -KETO ACETALS , 1974 .

[31]  D. Schomburg,et al.  A flexible hydroazulene synthesis , 1988 .

[32]  S. Martin,et al.  Novel intramolecular [4 + 2] cycloaddition reactions of enamines and enamides with unactivated dienes , 1980 .