127762-40-7Relevant academic research and scientific papers
Functionally Substituted Vinyl Carbanions, 42: Synthesis of the Top Half of Chlorothricolide
Hirsenkorn, Rolf,Schmidt, Richard R.
, p. 883 - 899 (2007/10/02)
β-Lithiated functionally substituted acrylates 2a-c prove to be versatile building blocks for spirotetronate syntheses useful in top half syntheses of the aglycon chlorothricolide 1 of the macrolide antibiotic chlorothricin.The electrophilic-nucleophilic cyclohexanone derivatives 27-cis/trans (with relative cis or trans relationship of the carboxylate group) required in this synthesis design are obtained via a cycloaddition route from pentenone in five steps.Generation of the dilithiated species from the acrylates 2a-c affords then the corresponding spirotetronates 32a-c, which serve as versatile intermediates in top half syntheses for different strategies in chlorothricolide total syntheses.Hydroxylation in the vinylic α-position of the tetronate moiety and selective phenylselenylation provide the spirotetronates 39a-cis/trans and 41a, which meet the requirements of a top half molecule.The same is true for a different strategy, which provides the aldehydes 42b-cis/trans.The latter are then converted into the fully functionalized spirotetronates 44b-cis/trans by treatment with vinylmagnesium bromide and subsequent hydroxylation at the vinylic α-position.The investigations delineate similar convenient strategies for the syntheses of kijanolide and tetronolide, which are the aglycon portions of the structurally related macrolide antibiotics kijanimicin and tetrocarcin, respectively.
INVESTIGATIONS FOR SYNTHESIZING CHLOROTHRICOLIDE
Schmidt, Richard R.,Hirsenkorn, Rolf
, p. 4357 - 4360 (2007/10/02)
Functionally substituted acrylates 8a,b obtained by direct lithiation of the corresponding acids, and cyclohexanone derivative 6 accessible in a five step sequence afforded spirotetronates 9a,b containing the carbon skeleton and the stereochemistry of the
