Which of the following amino acids would most likely be used as a precursor in the synthesis of Compound X, shown below? Compound X

Question

Which of the following amino acids would most likely be used as a precursor in the synthesis of Compound X, shown below?  Compound X

Quizplus · Accepted Answer

11ecba2d_127b_07cd_a3bf_fd0ac7157ff4_MD0008_00 Amino acids are distinguished by the chemical groups on their side chains, which confer different chemical and biological properties on those amino acids. Many amino acids have relatively simple functional groups, including alkyl chains (Ala, Leu, Ile, Val), alcohols (Ser, Thr), carboxylic acids (Glu, Asp), amides (Gln, Asn), amines (Lys), and thiols (Cys). A few amino acids have more complex side chains, such as imidazole (His) and indole (Trp) groups. The indole structure in the tryptophan (Trp) side chain is incorporated into several biologically important molecules, such as serotonin and melatonin. It is present in Compound X, and therefore tryptophan is the most likely amino acid precursor in the synthesis of the compound. (Choice A) The side chain of proline is a cyclic alkyl group that bonds to the nitrogen of the amino acid backbone in a five-membered ring. It is not present in Compound X. (Choice C) The side group of histidine is imidazole, a five-membered aromatic ring containing two nitrogen atoms. Compound X does not include imidazole. (Choice D) The side group of tyrosine is phenol. Compound X does not contain phenol. Educational objective: Each amino acid has a unique side chain that confers specific chemical and biological properties on that amino acid. Side chains may have relatively simple functional groups, such as alkyl chains, alcohols, and carboxylic acids, or they may have more complex groups, such as indole or imidazole.

Which of the Following Amino Acids Would Most Likely Be