Chem 109C Summer 2004 Problem Set: Peptide and Carbohydrate Chemistry, Assignments of Economics

Download Chem 109C Summer 2004 Problem Set: Peptide and Carbohydrate Chemistry and more Assignments Economics in PDF only on Docsity! Prob set 10, chem 109C summer 2004 1. What is the structure of L-valine at its isoelectric point? 2. What is the structure of L-arginine at pH 7? 3. Draw L-Ala-L-Ala and compare it with D-Ala-D-Ala. 4. Draw Ala-Gly-Lys in the zig-zag form. Place the N-terminus at the left. 5. Why is the methyl glycoside of mannose not a reducing sugar? Provide the structure of one that is. Draw it in its pyranose form. 6. What is the product of trimerization of styrene under mild acid catalysis? Formulate a mechanism. [How does this problem relate to our discussion of the Merrifield synthesis of peptides?] 7, 8. Formulate a mechanism. Assume the existence of a proton source. CHO OH "base" O OH How does this problem relate to our study of carbohydrate chemistry? 9. What is the product of the reaction of sodium acetate and benzyl chloride? How does this question relate to our study of peptide synthesis? 10. Indicate the reagents needed to accomplish the following overall transformation. 11. What amino acids make up the primary structure of the dipeptide generated above? Is it made up of natural or unnatural amino acids? How do you know? 12. Predict the product. How does this problem relate to our discussion of peptide synthesis? Formulate a mechanism for the transformation. Ph O H N N H O O O O HO H N NH2 O O O N HN NH2 O