Page 84 - Org 3 theoritical book 2024-25

Clinical Pharmacy PharmD - 2024/2025 Level 2 Pharmaceutical Organic Chemistry-3 (PC 305)
Synthesis of amino acids:

The Strecker Synthesis

Treating an aldehyde with ammonia and hydrogen cyanide produces an α-

aminonitrile.

Hydrolysis of the nitrile group of the α-aminonitrile converts the latter to an

α-amino acid.

Polypeptides and Proteins

• Amino acids are polymerized in living systems by enzymes that form amide

linkages from the amino group of one amino acid to the carboxyl group of
another.

• A molecule formed by joining amino acids together is called a peptide, and the
amide linkages in them are called peptide bonds or peptide linkages.

• Peptides that contain 2, 3, a few (3–10), or many amino acids are called
dipeptides, tripeptides, oligopeptides, and polypeptides, respectively.

• Proteins are polypeptides consisting of one or more polypeptide chains.

Hydrolysis of proteins:

When a protein or polypeptide is refluxed with 6M hydrochloric acid for 24 h,

hydrolysis of all the amide linkages usually takes place, liberating its constitutent

amino acids as a mixture.