Traceless sulfone linker cleavage triggered by ozonolysis: solid-phase synthesis of diverse α-β-unsaturated carbonyl compounds
作者:Yi-Fan Chang、Yi-Rui Jiang、Wei-Chieh Cheng
DOI:10.1016/j.tetlet.2007.11.064
日期:2008.1
The highly efficient and convenient protocol to prepare diverse α,β-unsaturated aldehydes, ketones, and acids via the parallel solid-phase synthesis is developed. The key sulfone linker cleavage strategy is performed by ozonolysis to generate a carbonyl moiety followed by base-mediated polymer-bound sulfinate elimination to release our desired molecules from the resin. All α,β-unsaturated carbonyl compounds
Palladium-Catalyzed Intramolecular Trost-Oppolzer-Type Alder-Ene Reaction of Dienyl Acetates to Cyclopentadienes
作者:Siddheshwar K. Bankar、Bara Singh、Pinku Tung、S. S. V. Ramasastry
DOI:10.1002/anie.201711797
日期:2018.2.5
cyclopentene‐fused heteroarenes by means of the Pd‐catalyzed Trost–Oppolzer‐type intramolecular Alder–ene reaction of 2,4‐pentadienyl acetates is described. This unprecedented transformation combines the electrophilic features of the Tsuji–Trost reaction with the nucleophilic features of the Alder–ene reaction. The overall outcome can be perceived as a hitherto unknown “acid‐free” iso‐Nazarov‐type cyclization. The
Aromatic dienoyl tetramic acids. Novel antibacterial agents with activity against anaerobes and staphylococci
作者:Terry Rosen、Prabhavathi B. Fernandes、Mary A. Marovich、Linus Shen、James Mao、Andre G. Pernet
DOI:10.1021/jm00125a022
日期:1989.5
Streptolydigin (1) and tirandamycin A (2) are typical members of the naturally occurring class of 3-dienoyltetramicacids. These compounds, which possess potent antibacterial activity particularly against anaerobes, have been shown to inhibit bacterial RNA polymerase. In contrast, tenuazonic acid (5), which lacks a complex dioxabicyclononane moiety and diene chromophore present in 1 and 2, exhibits
and diastereoselective [3 + 2] and [4 + 2] annulations of α,β-unsaturated imines with alkenes via allylic C(sp3)–H activation by half-sandwich rare-earth catalysts having different metal ion sizes. The reaction of α-methyl-substituted α,β-unsaturated aldimines with alkenes by a C5Me4SiMe3-ligated scandium catalyst took place in a trans-diastereoselective [3 + 2] annulation fashion via C(sp3)–H activation