Page 170 - Medicinal Chemistry Self Assessment
P. 170

Section 4  Whole Molecule Drug Evaluation

                                                                                                Answers






                                                                     2.13 Dabigatran Etexilate






            Thrombin is the enzyme responsible for catalyzing the conversion of fibrinogen to fibrin. The production of fibrin is
            important in the formation of sturdy blood clots. As you might expect, inhibition of thrombin prevents the forma-
            tion of fibrin. As shown in the diagram below, a catalytic triad of amino acids (Asp, His, Ser) found in the active site
            of thrombin is responsible for hydrolyzing a key peptide bond found within fibrinogen. Orientation of fibrinogen in
            the active site of thrombin relies on the interaction of a key tri-peptide sequence (D-Phe-Pro-Arg) found within the
                          Chapters 1.13/2.13 Concern about His (revised diagram + removed bolded names)
            structure fibrinogen with key amino acids in the enzyme active site.

                 Chapters 1.13/2.13 Concern about His (revised diagram + removed bolded names)

            Dabigatran etexilate is administered as a prodrug. In its active form, dabigatran etexilate is an orally active direct


            thrombin inhibitor used in the prevention of stroke and blood clots in patients diagnosed with atrial fibrillation.

                                          Thrombin Active Site
                                                                                                 Thrombin Active Site
                                 Thrombin Active Site                                   Thrombin Active Site
                                                                Thrombin catalyzed
                                                                 amide hydrolysis
                                                       Thrombin catalyzed
                                                        amide hydrolysis








                          Fibrinogen (D-Phe-Pro-Arg)
                                                                                  Fibrin

                 Fibrinogen (D-Phe-Pro-Arg)
                                                                         Fibrin
                          Chapters 1.13/2.13 (removed bold in drug name)


                 Chapters 1.13/2.13 (removed bold in drug name)











                                                          Dabigatran etexilate

                                                 Dabigatran etexilate
                          Chapters 1.13/2.13 (removed bold and centered text)

                 Chapters 1.13/2.13 (removed bold and centered text)


                                                             159
                                                3

                                       3
                                    1         2

                           1         2






                          D-Phe-Pro-Arg Tripeptide Sequence

                 D-Phe-Pro-Arg Tripeptide Sequence
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