Page 85 - Pharmaceutical Organic Chemmistry-3 (Theoritical book) 24-25
P. 85

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.
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