Synthesis of Uridine 5′‐[2‐S‐Pyridyl‐3‐thio‐α‐d‐galactopyranosyl Diphosphate]: Precursors of UDP‐Thiogal Sugar Nucleotide Donor Substrate for β‐1,4‐Galactosyltransferase

Abstract

The syntheses of a novel uridine diphosphate galactose (UDP‐Gal) analog, (UDP‐2,4,6‐tri‐O‐acetyl‐3‐S‐acetyl‐3‐thio‐α‐d‐galactopyranose) (11) and the thiolpyridine protected (Uridine 5′‐[3‐S‐(2‐S‐pyridyl)‐3‐thio‐α‐d‐galactopyranosyl diphosphate) analog (12) are described. The reported synthesis relies on the novel use of thiolpyridine to generate 12 which is a suitably protected intermediate for generating a UDP‐thioGal derivative by reduction prior to enzyme transfer via β‐1,4‐galactosyltransferase.

^†In honor and celebration of the 70th birthday of Professor Leroy B. Townsend.

Keywords:

• Sugar nucleotides
• β‐1,4‐galactosyltransferase
• Thio sugars
• Dithiodipyridine
• Thiopyridine derivatives

Acknowledgments

The authors acknowledge Magdalena Przydzial for her help in generating ESI‐MS data. Financial support from NIH AI33189, GM48049 are gratefully acknowledged.

Notes

^†In honor and celebration of the 70th birthday of Professor Leroy B. Townsend.