Synthesis and antifungal activity of 1-[(2-benzyloxy)phenyl]-2-(azol-1-yl)ethanone derivatives: exploring the scaffold flexibility.

Based on the N-(phenethyl)azole backbone of azole antifungals, we designed 1-[(2-benzyloxy)phenyl]-2-(azol-1-yl)ethanone derivatives 2 and 3, containing benzyloxyphenyl scaffold of croconazole. Also these compounds can be considered as flexible analogs, resulted from C2-C3 disconnection of 3'-chloro-3-imidazolylflavanone 1, recently described as antifungal agent. Thus, in this report, we describe the synthesis of 1-[(2-benzyloxy)phenyl]-2-(azol-1-yl)ethanone derivatives 2 and 3 and their biological evaluation against different pathogenic fungi. By comparing the antifungal activity profile of flexible compounds 2 and 3 with that of rigid analog 1, it can be inferred that lower susceptibilities (higher minimum inhibitory concentrations) were observed with flexible compounds. However, among the synthesized compounds, 1-[2-(2,4-dichlorobenzyloxy)phenyl]-2-(1H-imidazol-1-yl)ethanone hydrochloride (2g) showed comparable or more potent antifungal activity in comparison with fluconazole as a standard drug.