Microbial Hydrolysis of Racemic β-Aryl-γ-ethylidene-γ-lactones and Antifeedant Activity of the Products against Panzer.

Hydrolysis of (±)-β-aryl-γ-ethylidene-γ-lactones by fungal strain AM370 afforded (−)-()-γ-ethylidene-γ-lactones ⁻ and (+)-()-γ-ketoacids ⁻. Enantiomeric purity of the unreacted lactones was strictly related to a size of an aryl substituent at C-4 of γ-lactone ring, with the highest (77%) obtained for the (−)-()-γ-ethylidene-γ-lactone possessing unsubstituted benzene ring () and the lowest one (15%) determined for the (−)-()-γ-ethylidene-γ-lactone with bulky 1,3-benzodioxole system (). Lactones ⁻, both racemic and enantiomerically enriched, as well as products of their hydrolysis showed varying degrees of feeding deterrent activity against lesser mealworm, Panzer, which depended on the structure of the compound and the developmental stage of the lesser mealworm.

Chemoenzymatic Synthesis of trans-β-Aryl-δ-hydroxy-γ-lactones and Enzymatic Kinetic Resolution of Their Racemic Mixtures.

Two novel and convenient routes to obtain enantiomerically enriched -β-aryl-δ-hydroxy-γ-lactones - with potential antifeedant and anticancer activity were developed. In the first method starting from corresponding enantiomers of γ,δ-unsaturated esters - derived from enzymatically resolved allyl alcohols -, both enantiomers of hydroxylactones - were synthesized with high enantiomeric excesses (73%-97%). Configurations of the stereogenic centers of the synthesized compounds were assigned based on the mechanism of acidic lactonization of esters - in the presence of -chloroperbenzoic acid (-CPBA).

Lactones 46. Synthesis, antifeedant and antibacterial activity of γ-lactones with a p-methoxyphenyl substituent.

Background: Lactones are well known for their biological activity. Grosheimin and repin are potent deterrents against storage pests. The unsaturated lactones have exhibited a wide spectrum of antibacterial activity.