A 3-Amino-4-hydroxy-3-cyclobutene-1,2-dione-Containing Glutamate Analog Exhibiting High Affinity to Excitatory Amino Acid Receptors
摘要:
The syntheses of several novel N-(hydroxydioxocyclobutenyl)-containing analogues of gamma-aminobutyric acid and L-glutamate were undertaken to test the hypothesis that derivatives of 3,4-dihydroxy-3-cyclobutene-1,2-dione (squaric acid), such as 3-amino-4-hydroxy-3-cyclobutene-1,2-dione, could serve as a replacement for the carboxylate moiety in neurochemically interesting molecules. The syntheses were successfully accomplished by preparation of a suitably protected diamine or diamino acid followed by reaction with diethyl squarate. Subsequent deprotection resulted in the isolation of the corresponding N-(hydroxydioxocyclobutenyl)-containing analogues 13, 14, and 18. These analogues were screened as displacers in various neurochemical binding site assays. The L-glutamate analogue 18, which showed high affinity as a displacer for kainate and AMPA binding, was also examined for agonist potency for CA1 pyramidal neurons of the rat hippocampal slice preparation. It rivaled AMPA as one of the most potent agonists for depolarizing pyramidal neurons in medium containing 2.4 mM Mg+2 ions in which kainate/AMPA receptors are active but NMDA receptors are inhibited (IC50 = 1.1 mu M). It was 1 order of magnitude less potent for depolarizing pyramidal neurons under conditions in which kainate/AMPA receptors were inhibited by 10 mu M CNQX but NMDA receptors were active in 0.1 mM Mg+2-containing medium (IC50 = 10 mu M). Compound 18 did not induce sensitization of CA1 pyramidal cells to depolarization by phosphonate analogues of glutamate (the QUIS-effect).
Herein we report the design, synthesis and assessment of the first example of a squaramide-based self-immolative system triggered by an enzymatic reduction. We have proved that the release of the alkylating agent N′,N′-(bis(2-chloroethyl)benzene)-1,4-diamine (ANM) provokes a dramatic reduction of the survival factor in glioblastoma cells, evidencing the suitability of the squaramide-based spacer for drug
A novel tertiary squaramido-based reverse-turn module SQ is reported, and its conformational properties are evaluated. This module is easily incorporated into a alpha-peptide sequence by conventional solid-phase peptide synthesis. The structure characterization of the hybrid squaramido-peptide 4 is described, showing that the turn segment induces the formation of hairpin structures in water through the formation of both alpha SQ- and beta SQ-turns.
[EN] CONJUGATES OF CHEMOTHERAPY AGENTS AND TISSUE-BINDING SMALL MOLECULES, COMPOSITIONS AND METHODS THEREOF<br/>[FR] CONJUGUÉS D'AGENTS DE CHIMIOTHÉRAPIE ET DE PETITES MOLÉCULES DE FIXATION TISSULAIRE, COMPOSITIONS ET MÉTHODES ASSOCIÉES
申请人:[en]CANWELL BIOTECH LIMITED
公开号:WO2023151513A1
公开(公告)日:2023-08-17
The invention provides novel conjugates of tissue-binding small molecules and therapeutic agents and pharmaceutical compositions thereof, and their use in and methods of treatment of certain diseases or conditions (e.g., cancer).