Synthesis and Antibacterial Activity of Some Glucosyl- and Ribosyl-Pyridazin-3-ones

Abstract

Reaction of 5,6-diphenylpyridazin-3(2H)-one 1a,b with 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl bromide 2 in K₂CO₃/acetone gave 5,6-diphenyl-N²-(2′,3′,4′,6′-tetra-O-acetyl-β-D-glucopyranosyl)pyridazin-3-one 5a,b. The same nucleosides 5a,b were obtained by reaction of 1a,b with peracetylated glucose 3 under MW irradiation. Mercuration of 1a,b followed by reaction with glucosyl bromide 2 gave the same nucleosides 5a,b. The riboside 4-cyano-5,6-diphenyl-N²-(2′,3′,5′-tri-O-acetyl-β-D-ribofuranosyl)-pyridazin-3-one 8 was obtained by reaction of 4-cyanopyridazinone 1b with peracetylated ribose 7 under MW irradiation. The deprotected nucleosides 6a,b and 9 were obtained by stirring of 5a,b and 8 in methanol and TEA/H₂O. The structure was confirmed using ¹H and ¹³C-NMR spectra. Selected members of these compounds were screened for antibacterial activity.

Keywords:

• 5,6-Diphenylpyridazin-3-one
• pyridazine nucleoside
• micowave and antibacterial activity