Regioselective synthesis and antimicrobial activities of some novel aryloxyacetic acid derivatives

Reaction of aryloxyacetic acid hydrazides 1a,b with α-haloketones such as hydrazonoyl chlorides 2a,b; phenacyl bromides 6a,b; and 2-chloro-N-(1,3-thiazol-2-yl)acetamide 10 led to the formation N-(4-halophenyl)-2-[2-(aryloxyacetyl)hydrazinylidene]propanehydrazonoyl chloride 3a–d; (ethene-1,2-diyl)bis-2-(naphthalen-2-yloxy)acetohydrazides 9a,b; and 2-[(2-aryloxyacetyl)hydrazinyl)]-N-(1,3-thiazol-2-yl)acetamides 11a,b; respectively. The nucleophilic substitution reaction of 3a–d with thiophenol and sodium benzenesulfinate furnished the corresponding hydrazinylidenepropanehydrazonothioates 4a–d and sulfones 5a–d, respectively. The antimicrobial activities of the synthesized compounds were evaluated. The obtained data indicated that the majority of the tested compounds exhibited antibacterial activity while all those compounds showed antifungal activity. Sulfone 5d showed greater effect with all tested organism than well known antibacterial and antifungal agents with minimal inhibitory concentration (MIC) ranged between 4.125 and 16.5 μg/mL.

Graphical abstractSulfone 5d showed greater effect with all tested organism with minimal inhibitory concentration (MIC) ranged between 4.125 and 16.5 μg/mL.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A series of novel aryloxyacetic acid derivatives have been synthesized. ► The structure of compound 5b was proved by X-ray single crystal analysis. ► Antimicrobial studies of the newly synthesized compounds showed promising activity. ► Compound 5d showed greater antimicrobial effect than known standard drugs.