Acylative kinetic resolution of racemic methyl-substituted cyclic alkylamines with 2,5-dioxopyrrolidin-1-yl (R)-2-phenoxypropanoate

Diastereoselective acylation of a number of racemic methyl-substituted cyclic alkylamines with active esters of 2-phenoxypropanoic acid was studied in detail. Ester of (R)-2-phenoxypropanoic acid and N-hydroxysuccinimide was found to be...

STUDY OF BIOLOGICAL ACTIVITY OF RACEMIC AND OPTICALLY ACTIVE ESTERS OF NAPHTHENIC AND FATTY ACIDS BASED ON UNSATURATED OXYESTERS

Petrochemical products based on petroleum naphthenic acids have special properties. Esters of naphthenic acids possess practically valuable organic compounds. The aim of this work is the development of effective methods for the preparation of aromatic esters based on naphthenic and individual fatty acids which is a very promising direction in the medicine practice. The synthesis of unsaturated racemic and chiral oxyethers was carried out on the basis of the interaction of chloromethylpropargyl (allyl) esters with carbonyl compounds with the participation of metallic zinc. Also, to study the biological activity, racemic and optically active esters were synthesized based on naphthenic acids and unsaturated racemic and chiral oxyesters. As test cultures used: gram-positive (Staphylo-coccus aureus-Staphylococcus aureus), gram-negative (Pseudomonas aeruginosa – Pseu-domonas aeruginosa, Escherichia coli) bacteria, as well as yeast-like fungi of the genus Candida - Candida albicans. Analysis of the biological activity of the synthesized compounds showed that optically active bicyclo [2.2.1] hept-5-ene-2-methylol monoesters have higher antimicrobial and antifungal activity compared to their racemic analogs and drugs used in medicine.

Nickel-Catalyzed Decarboxylative Coupling of Redox-Active Esters with Aliphatic Aldehydes

The addition of alkyl fragments to aliphatic aldehydes is a highly desirable transformation for fragment couplings, yet existing methods come with operational challenges related to the basicity and instability of the nucleophilic reagents commonly employed. We report herein that nickel catalysis using a readily available bioxazoline (BiOx) ligand can catalyze the reductive coupling of redox-active esters with aliphatic aldehydes using zinc metal as the reducing agent to deliver silyl-protected secondary alcohols. This protocol is operationally simple, proceeds under mild conditions, and tolerates a variety of functional groups. Initial mechanistic studies suggest a radical chain pathway. Additionally, alkyl tosylates and epoxides are suitable alkyl precursors to this transformation providing a versatile suite of catalytic reactions for the functionalization of aliphatic aldehydes.

Transition metal-free photodecarboxylative amination of redox-active esters with diazirines

Due to the prevalence of nitrogen-containing compounds in medicine, materials, and related fields, the search for general, mild methods for electrophilic amination remains an area of intense research. Diazirines have been recently demonstrated to serve as electrophilic amination reagents that afford diaziridines, versatile heterocycles that are readily transformed into amines, hydrazines, and a variety of nitrogen-containing heterocycles. Here we report the phosphine-mediated, photodecarboxylative amination of redox-active esters with diazirines. This method is transition metal-free, uses inexpensive photoactivators under mild conditions, and offers a significantly enhanced scope and yields for primary redox-active esters. Furthermore, the stability of diazirines to blue light (456 nm) is demonstrated, paving the way for further research into other photochemical amination methods with these unique heterocycles.