Stepwise Cross-Couplings of a Dibromo-γ-methylenebutenolide as an Access to Z-Configured α-Alkenyl-γ-alkylidenebutenolides. Straightforward Synthesis of the Antibiotic Lissoclinolide
Stepwise Cross-Couplings of a Dibromo-γ-methylenebutenolide as an Access to Z-Configured α-Alkenyl-γ-alkylidenebutenolides. Straightforward Synthesis of the Antibiotic Lissoclinolide
Palladium-Catalyzed Asymmetric Allylic Alkylation of Cyclic Dienol Carbonates: Efficient Route to Enantioenriched γ-Butenolides Bearing an All-Carbon α-Quaternary Stereogenic Center
Allyl dienol carbonates (1) served as substrates for the title reaction to afford the furanones 2 in both high yields and high enantioselectivities. These furanones were eventually converted into valuable buildingblocks including γ‐tertiary and γ‐quaternary furanones (3) as well as β‐quaternary butyrolactones (4). This method was used as a key step in the totalsynthesis of (−)‐nephrosteranic acid
A new method for the stereoselective synthesis of (±)-avenaciolide and its analogues via methoxycarbonyl- or anisyloxycarbonyldi-γ-lactones, which could be easily prepared by the reaction of γ-substituted α-bromobutenolides with sodium salt of methyl or anisyl malonamate in good yields, was described.
Microwave Assisted Suzuki Reactions for the Preparation of the Antifungal 3-Aryl-5-methyl-2,5-dihydrofuran-2-ones
作者:Paul A. Worthington、Christopher J. Mathews、John Taylor、Melloney J. Tyte
DOI:10.1055/s-2005-862367
日期:——
The Suzuki cross-coupling reaction of arylboronic acids with a bromo-furanone has been developed to prepare a series of substituted 2,5-dihydrofuran-2-ones related to the fungal metabolite, incrustoporin. A protocol of microwave heating was introduced to improve synthesis throughput.
α-Bromo-α,β-unsaturatedesters and α-bromobutenolides reacted with sodium salts of methyl malonamates to afford cyclopropanes, α-methoxycarbonyllactams and 5-amino-4-methoxycarbonyl-2,3-dihydrofurans. The last compounds could be easily converted into α-methoxycarbonyl-γ-lactones. The ratio of these compounds formed is influenced by the structures of both malonamates and unsaturated compounds, especially
Biosynthesis of
<i>Pseudomonas</i>
‐Derived Butenolides
作者:Martin Klapper、Kevin Schlabach、André Paschold、Shuaibing Zhang、Somak Chowdhury、Klaus‐Dieter Menzel、Miriam A. Rosenbaum、Pierre Stallforth
DOI:10.1002/anie.201914154
日期:2020.3.27
Butenolides are well-known signaling molecules in Gram-positive bacteria. Here, we describe a novel class of butenolides isolated from a Gram-negative Pseudomonas strain, the styrolides. Structure elucidation was aided by the total synthesis of styrolide A. Transposon mutagenesis enabled us to identify the styrolide biosynthetic gene cluster, and by using a homology search, we discovered the related