Automated iterative solution-phase synthesis of rhamnogalacturonan I fragments

ORGN 628

Yonghai Chai, ychai@iastate.edu and Nicola L. Pohl, npohl@iastate.edu. Department of Chemistry and the Plant Sciences Institute, Iowa State University, Gilman Hall, Ames, IA 50011
Rhamnogalacturonan I (RG I) is an important component of pectin, a complex family of plant primary cell wall polysaccharides. Pectins have roles in plant growth, development and disease resistance and are used as gelling agents in the food industry and coatings in medical devices. However, little is known about the biosynthesis of RG I and its specific molecular interactions; well-defined structures are difficult to isolate from heterogeneous natural sources. To access specific molecular fragments for such studies, we have developed a flexible strategy to access a range of RG I structures from five different rhamnose and galactose building blocks. These building blocks serve as inputs for a new fluorous-tag-based automated protocol for the iterative solution-phase synthesis of a discrete library of rhamnogalacturonan I fragments.