Antipicornavirus activity of tetrazole analogues related to disoxaril

A series of tetrazole analogues of Win 54954, a broad-spectrum antipicornavirus compound, has been synthesized to address the acid lability of the oxazoline ring of this series of compounds. The results of X-ray crystallography studies of several members of the oxazoline series bound to human rhinovirus type 1A and 14 have been used to design compounds in the tetrazole series with a broad spectrum of activity. Compound 16b, which has a three-carbon linkage between the isoxazole and phenyl rings and a propyl chain extending from the isoxazole ring, exhibiting an MIC80 for 15 rhinovirus serotypes of 0.20 microM as compared to 0.40 microM for Win 54954. X-ray studies of 16b bound to human rhinovirus-14 show that the propyl side chain extends into a pore in the binding site with the possibility of hydrophobic interactions with a pocket formed by Leu106 and a portion of Ser107.