TY - JOUR

T1 - Syntheses of retipolide E and ornatipolide, 14-membered biaryl-ether macrolactones from mushrooms

AU - Ingerl, Andrea

AU - Justus, Karl

AU - Hellwig, Veronika

AU - Steglich, Wolfgang

N1 - Funding Information: We thank the Fonds der Chemischen Industrie for financial support and Prof. H. Shibata, Shinshu University, for kindly comparing compound 6 with authentic ornatipolide. We also thank Dr. Bert Steffan for high field NMR spectra and Drs. Richard Allen and Jörg-Dieter Klamann for linguistic improvements.

PY - 2007/7/9

Y1 - 2007/7/9

N2 - Two approaches for the total synthesis of the spiromacrolide retipolide E (5) are described, the first using a modified Mitsunobu reaction as key step for the formation of the strained 14-membered macrolactone, the second a nucleophilic aromatic substitution (S NAr). In the first approach an α-oxomacrolactone 15 was obtained, which could either be converted into ornatipolide (6) or further transformed into racemic retipolide E [(R,S)-5] by directed aldol condensation with a methyl arylpyruvate. The second approach allowed the synthesis of either racemic or enantiomerically pure retipolide E (5). In the latter case Evans' methodology was used for the introduction of stereogenic center via stereoselective alkylation. The oxazolidinone auxiliary was removed under mild conditions by exchange for 2-arylethanol 22 with Otera's distannoxane catalyst. Synthetic retipolide E allowed the identification of this biosynthetic intermediate in the fruit bodies of the North American mushroom Retiboletus retipes.

AB - Two approaches for the total synthesis of the spiromacrolide retipolide E (5) are described, the first using a modified Mitsunobu reaction as key step for the formation of the strained 14-membered macrolactone, the second a nucleophilic aromatic substitution (S NAr). In the first approach an α-oxomacrolactone 15 was obtained, which could either be converted into ornatipolide (6) or further transformed into racemic retipolide E [(R,S)-5] by directed aldol condensation with a methyl arylpyruvate. The second approach allowed the synthesis of either racemic or enantiomerically pure retipolide E (5). In the latter case Evans' methodology was used for the introduction of stereogenic center via stereoselective alkylation. The oxazolidinone auxiliary was removed under mild conditions by exchange for 2-arylethanol 22 with Otera's distannoxane catalyst. Synthetic retipolide E allowed the identification of this biosynthetic intermediate in the fruit bodies of the North American mushroom Retiboletus retipes.

KW - Chemistry

UR - http://www.scopus.com/inward/record.url?scp=34249318436&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/d4be7a0c-910c-3d6e-a8f3-239deae9a036/

U2 - 10.1016/j.tet.2007.03.022

DO - 10.1016/j.tet.2007.03.022

M3 - Journal articles

VL - 63

SP - 6548

EP - 6557

JO - Tetrahedron

JF - Tetrahedron

SN - 0040-4020

IS - 28

ER -