Nucleosides 5¹⁵: Synthesis of Novel 1,2,4-Triazolo[3,4-c]-1,2,4-Triazole Nucleosides

Abstract

Ribosylation of 3-methylthio-5-phenyl-1,2,4-triazole (1) with ribose derivative 2 gave the protected 1,2,4-triazole-nucleoside 3, which reacted with hydrazine hydrate to afford the 3-hydrazino-1,2,4-triazole derivative 5. Reaction of 5 with aromatic aldehydes yielded the corresponding hydrazones 6, which cyclized under bromination in acetic acid to give 8. Debenzoylation of 8 afforded novel 1,2,4-triazolo[3,4-c]-1,2,4-triazole nucleosides 9.

Keywords:

• Ribosylation
• 3-methylthio-5-phenyl-1,2,4-triazole
• 1,2,4-triazole-nucleoside
• 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribofuranose
• 1,2,4-triazolo[3,4-c]-1,2,4-triazole nucleosides

Acknowledgments

Present address for M.A.N.M.: Taif University, Faculty of Science, Department of Chemistry Taif, Saudi Arabia.

The authors thank den Deutschen Forschungsgemeinschaft (DFG) for the financial support. The authors also thank Prof. Dr. Helmut Duddeck, Institut fuer Organische Chemie, Hannover, Germany for measuring the NOE-¹H NMR spectrum of compound 3.