Questions from Organic Chemistry

Q: The enolate of an ester can be treated with a ketone to

The enolate of an ester can be treated with a ketone to give a β-hydroxy ester. Draw a mechanism for this aldol-like reaction.

Q: The tetrapeptide Val-Lys-Ala-Phe is cleaved into

The tetrapeptide Val-Lys-Ala-Phe is cleaved into two fragments upon treatment with trypsin. Identify the sequence of a tetrapeptide that will produce the same two fragments when treated with chymotryp...

Q: Consider the structure of the following cyclic octapeptide. Would cleavage of

Consider the structure of the following cyclic octapeptide. Would cleavage of this peptide with trypsin produce different fragments than cleavage with chymotrypsin? Explain.

Q: Draw all of the steps and reagents necessary to prepare each of

Draw all of the steps and reagents necessary to prepare each of the following dipeptides from their corresponding amino acids: a. Trp-Met b. Ala- le c. Leu-Val

Q: Draw all of the steps and reagents necessary to prepare a tripeptide

Draw all of the steps and reagents necessary to prepare a tripeptide with the sequence le-Phe-Gly

Q: Draw all of the steps and reagents necessary to prepare a pentapeptide

Draw all of the steps and reagents necessary to prepare a pentapeptide with the sequence Leu-Val-Phe- le-Ala.

Q: Identify all of the steps necessary to prepare each of the following

Identify all of the steps necessary to prepare each of the following peptides with a Merrifield synthesis: a. Phe-Leu-Val-Phe b. Ala-Val-Leu- le

Q: Identify the sequence of the tripeptide that would be formed from the

Identify the sequence of the tripeptide that would be formed from the following order of reagents. Clearly label the C terminus and N terminus of the tripeptide.

Q: Below is the primary structure for a peptide. Identify the regions

Below is the primary structure for a peptide. Identify the regions that are most likely to form β pleated sheets. Trp-His-Pro-Ala-Gly-Gly-Ala-Val-His-Cys-Asp-Ser-Arg-Arg-Ala-Gly-Ala-Phe

Q: Draw a bondline structure showing the zwitterionic form of each

Draw a bondline structure showing the zwitterionic form of each of the following amino acids: a. L-Valine b. L-Tryptophan c. L-Glutamine d. L-Proline