Synthesis and Evaluation of Guanidine-Containing Schiff Base Copper(II), Zinc(II), and Iron(III) Chelates as Trypsin Inhibitors
作者:Eiko Toyota、Haruo Sekizaki、Kunihiko Itoh、Kazutaka Tanizawa
DOI:10.1248/cpb.51.625
日期:——
3-Formyl-4-hydroxyphenylguanidine hydrochloride and its Schiff base copper(II), zinc(II), and iron(III) chelates were synthesized and their inhibitory activity against bovine β-trypsin were determined. Syntheses of Schiff base metal chelates were carried out from 3-formyl-4-hydroxyphenylguanidine, various L-amino acids, and divalent metal acetate. Their structures were established on the basis of spectroscopic evidence and elemental analysis. The inhibitory activity of these chelates against bovine β-trypsin was determined. The guanidine-containing copper(II) and zinc(II) chelates behaved as potent competitive inhibitors of trypsin. However, similar inhibitory activity was not observed for guanidine-containing iron(III) chelates. The inhibition constants (Ki values, ca. 10−5 M) of guanidine-containing Schiff base copper(II) and zinc(II) chelates were slightly lower than those (ca. 10−6 M) of the corresponding amidine-containing Schiff base chelates with regard to bovine trypsin.
3-甲酰基-4-羟基苯基胍盐酸盐及其席夫碱铜(II)、锌(II)和铁(III)螯合物被合成,并测定其对牛β-胰蛋白酶的抑制活性。席夫碱金属螯合物由3-甲酰基-4-羟基苯基胍、各种L-氨基酸和二价金属乙酸盐合成。根据光谱证据和元素分析确定其结构。测定这些螯合物对牛β-胰蛋白酶的抑制活性。含胍的铜(II)和锌(II)螯合物表现出胰蛋白酶的强效竞争性抑制剂。然而,含胍的铁(III)螯合物没有观察到类似的抑制活性。含胍的席夫碱铜(II)和锌(II)螯合物的抑制常数(Ki值,约10−5M)略低于牛胰蛋白酶中相应含脒的席夫碱螯合物的抑制常数(约10−6M)。