Total Synthesis of Diverse Tetramic Acid Bearing cis-Decalin Natural Products
Haoran Dong, Dachao Hu, Benke Hong, Jin Wang, and Xiaoguang Lei*
Angew. Chem. Int. Ed. 2023, e202301872
We here report the first total syntheses of four natural antibiotics vermisporin (1), PF1052/AB4015-A (2), AB4015-L (3), AB4015-B (4) and one hydrogenated natural product derivative AB4015-A2 (5) that all feature a tetramic acid bearing cis-decalin ring. The construction of the functionalized cis-decalin ring was achieved by a diastereoselective intramolecular Diels-Alder (IMDA) reaction which underwent a rare endo-boat transition state. Through an intramolecular neighboring-group-oriented strategy, the sterically hindered epoxy group in vermisporin (1), PF1052/AB4015-A (2) and AB4015-L (3) was installed efficiently. A one-pot aminolysis/Dieckmann-condensation cascade using L-amino acid derivatives afforded the desired tetramic acid structure. The total synthesis led to the unambiguous verification of the absolute configuration of these natural products
Total Synthesis of Diverse Tetramic Acid Bearing cis-Decalin Natural Products
Haoran Dong, Dachao Hu, Benke Hong, Jin Wang, and Xiaoguang Lei*
Angew. Chem. Int. Ed. 2023, e202301872
We here report the first total syntheses of four natural antibiotics vermisporin (1), PF1052/AB4015-A (2), AB4015-L (3), AB4015-B (4) and one hydrogenated natural product derivative AB4015-A2 (5) that all feature a tetramic acid bearing cis-decalin ring. The construction of the functionalized cis-decalin ring was achieved by a diastereoselective intramolecular Diels-Alder (IMDA) reaction which underwent a rare endo-boat transition state. Through an intramolecular neighboring-group-oriented strategy, the sterically hindered epoxy group in vermisporin (1), PF1052/AB4015-A (2) and AB4015-L (3) was installed efficiently. A one-pot aminolysis/Dieckmann-condensation cascade using L-amino acid derivatives afforded the desired tetramic acid structure. The total synthesis led to the unambiguous verification of the absolute configuration of these natural products