Five new silver camphorimine complexes of general formula [Ag(NO3)(Y)L] were synthesized and fully characterized using spectroscopic and analytical techniques. The structure of [Ag(NO3)(OC10H14NC6H4NC10H14O)] () was analyzed using single crystal X-ray diffraction, showing that it arranges as a coordination polymer formed by sequential Ag(NO3) units bridged by the bi-camphor ligand (). The antimicrobial properties of the new complexes were screened using the disk diffusion method and their Minimal Inhibitory Concentrations (MIC) were assessed against selected bacterial strains of the Gram-positive Staphylococcus aureus and the Gram-negative Escherichia coli, Pseudomonas aeruginosa, and Burkholderia contaminans. The lowest MICs were observed for , with estimated values of 72, 20, 32 and 19 μg mL(-1) for S. aureus, E. coli, B. contaminans, and P. aeruginosa, respectively. In the case of S. aureus, similar MIC values were obtained for silver nitrate and compound . All five compounds were bactericidal when used in concentrations equal or above the MIC value, as found by enumerating the total colony forming units (CFUs) after incubation in their presence.

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Recently, we reported the use of a sequence of alkylation and dehydration methodologies to obtain new non‐proteinogenic amino acids (N‐ethyl α,β‐dehydroamino acids) from the methyl esters of N‐(4‐nitrophenylsulfonyl) β‐hydroxy amino acids. Thus, it was possible to obtain for the first time, non‐natural amino acids that incorporate both N‐ethyl and α,β‐dehydro moieties. Herein, we report the application of this N‐alkylation procedure to several methyl esters of β,β‐dibromo and β‐bromo β‐substituted dehydroamino acids protected with standard amine protecting groups such as tert‐butyloxycarbonyl, benzyloxycarbonyl, and (4‐nitrobenzyl)oxycarbonyl, as well as acyl and sulfonyl groups. The procedure allows the synthesis of the methyl esters of N‐protected N‐ethyl β,β‐dibromo and N‐ethyl β‐bromo β‐substituted dehydroamino acids in fair to high yields. Some of these N‐ethylated dehydroamino acid derivatives were used as substrates in cross‐coupling reactions to give β,β‐disubstituted N‐ethyldehydroalanine derivatives.