title: [Synthetic inhibitors of serine proteinases. 13. Quantitative structure-activity relationship for inhibition of trypsin and thrombin by 4-amidinophenyl compounds with a ketone structure].
abstract: To establish quantitative structure-activity relationships for the inhibition of trypsin, plasmin and thrombin by 4-amidinophenyl compounds with a keto group, attempts have been made to detect correlations between data on inhibition and substituent constants. The inhibitor activity of the derivatives is described by lipophilic or steric substituent constants using linear free energy relationships. To describe the action of beta-ketones, an additional sigma I term is necessary. The lipophilic or steric term stands for binding of the inhibitor side chain to a second hydrophobic binding site of the enzyme. The electronic term describing inductive influences on the keto group suggests the contribution of the beta-keto group to the enzyme inhibitor binding via a tetrahedral conformation of the carbonyl carbon.
mesh_terms: D001665:Binding Sites; D005341:Fibrinolysin / Q000037:antagonists & inhibitors*; D006801:Humans; D007659:Ketones / Q000494:pharmacology*; D011480:Protease Inhibitors; D013329:Structure-Activity Relationship; D013917:Thrombin / Q000037:antagonists & inhibitors*; D014361:Trypsin Inhibitors / Q000097:blood*
chemical_list: D007659:Ketones; D011480:Protease Inhibitors; D014361:Trypsin Inhibitors; D013917:Thrombin; D005341:Fibrinolysin
vernacular_title: Synthetische Hemmstoffe der Serinproteinasen. 13. Quantitative Struktur-Wirkungs-Beziehungen bei der Hemmung von Trypsin, Plasmin und Thrombin durch 4-Amidinophenylverbindungen mit Ketonstruktur