Synthesis of α-Alkylidene-γ-butyrolactones

Synthesis of Ru alkylidene complexes

The present work describes the robust synthesis of Ru alkylidene complexes (PCy(3))(2)Cl(2)Ru=CHR - precursors for metathesis catalysts. Moreover, the dynamic behavior of complexes where R = 2-naphthyl and 2-thienyl was studied. (1)H NMR techniques were employed to establish the preferred conformations in solution for both complexes and the energy barrier for rotation around single (Ru=)CH-C(th...

Target analysis of α-alkylidene-γ-butyrolactones in uropathogenic E. coli.

α-Alkylidene-γ-butyrolactones are quite common in nature and exhibit a broad spectrum of biological activities. We therefore synthesized a small library of xanthatine inspired α-alkylidene-γ-butyrolactones to screen non-pathogenic and uropathogenic E. coli strains by activity based protein profiling (ABPP). The identified targets are involved in cellular redox processes and give first insight i...

Catalytic Asymmetric Synthesis of Butenolides and Butyrolactones

γ-Butenolides, γ-butyrolactones, and derivatives, especially in enantiomerically pure form, constitute the structural core of numerous natural products which display an impressive range of biological activities which are important for the development of novel physiological and therapeutic agents. Furthermore, optically active γ-butenolides and γ-butyrolactones serve also as a prominent class of...

Highly enantioselective syntheses of functionalized alpha-methylene-gamma-butyrolactones via Rh(I)-catalyzed intramolecular Alder ene reaction: application to formal synthesis of (+)-pilocarpine.

A highly enantioselective Rh(I)-catalyzed intramolecular Alder ene reaction has been developed. The desired products, 3-vinyl, vinyl acetate, and vinyl ether-substitued alpha-methylene-gamma-butyrolactones were formed in high yields. Aldehydes were produced with the formation of gamma-lactones when alcohols were substituted at allylic position in the substrates. All reactions with listed substr...

Mixed Acylais; Synthesis of Alkylidene Carboxylate Formates