Inhibition of Cellobiohydrolases fromTrichoderma reesei. Synthesis and Evaluation of Some Glucose-, Cellobiose-, and Cellotriose-Derived Hydroximolactams andImidazoles
摘要:
The lactam 16, the hydroximolactams 8, 20, 23, and 27, and the imidazole 32 were prepared following known methods. They were tested together with the known tetrazole 35 and the hydroximolactams 2 and 36 as inhibitors of the cellobiohydrolases Cel7A and Cel6A from Trichoderma reesei. Cel7A is only weakly inhibited by these compounds. Comparing their inhibitory activity evidences the importance of occupying subsites tl and +2. We results strongly suggest that the shape of none of the variants of the lactone-type inhibitor motif embodied by these inhibitors is complementary to the subsite - 1, i.e.,analogous to the transition state. Cel6A is rather strongly inhibited by the cellobiose analogues 20, 23, and 32, and by the cellotriose analogue 27. Their relative inhibitory activities evidence that binding at subsite -2 depends upon the shape of the moiety occupying subsite - 1. There is only a small difference between the inhibition by the hydroximolactams 20 and 23, which may be (partially) protonated by the catalytic acid of either anti- or syn-protonating glycosidases, and the imidazole 32, which can only be protonated by anti-protonating glycosidases. The results strongly suggest that shape requirements must be met by glycosidase inhibitors before they can be used to characterize the proton trajectory of glycosidases.
Inhibition of Cellobiohydrolases fromTrichoderma reesei. Synthesis and Evaluation of Some Glucose-, Cellobiose-, and Cellotriose-Derived Hydroximolactams andImidazoles
摘要:
The lactam 16, the hydroximolactams 8, 20, 23, and 27, and the imidazole 32 were prepared following known methods. They were tested together with the known tetrazole 35 and the hydroximolactams 2 and 36 as inhibitors of the cellobiohydrolases Cel7A and Cel6A from Trichoderma reesei. Cel7A is only weakly inhibited by these compounds. Comparing their inhibitory activity evidences the importance of occupying subsites tl and +2. We results strongly suggest that the shape of none of the variants of the lactone-type inhibitor motif embodied by these inhibitors is complementary to the subsite - 1, i.e.,analogous to the transition state. Cel6A is rather strongly inhibited by the cellobiose analogues 20, 23, and 32, and by the cellotriose analogue 27. Their relative inhibitory activities evidence that binding at subsite -2 depends upon the shape of the moiety occupying subsite - 1. There is only a small difference between the inhibition by the hydroximolactams 20 and 23, which may be (partially) protonated by the catalytic acid of either anti- or syn-protonating glycosidases, and the imidazole 32, which can only be protonated by anti-protonating glycosidases. The results strongly suggest that shape requirements must be met by glycosidase inhibitors before they can be used to characterize the proton trajectory of glycosidases.
An Advantageous Synthesis of 5,6,7,8-Tetra-Hydrotetrazolo[1,5-a]Pyridines
作者:Stefan Vonhoff、Andrea Vasella
DOI:10.1080/00397919908085802
日期:1999.2
Abstract The one-step synthesis of various O -benzyl-protected glyconotetrazoles from the corresponding glyconolactams is reported. The method is superior to the previously employed cycloaddition of azidonitriles as it uses readily available starting materials and leads to higher yields.
Inhibition of Cellobiohydrolases fromTrichoderma reesei. Synthesis and Evaluation of Some Glucose-, Cellobiose-, and Cellotriose-Derived Hydroximolactams andImidazoles
The lactam 16, the hydroximolactams 8, 20, 23, and 27, and the imidazole 32 were prepared following known methods. They were tested together with the known tetrazole 35 and the hydroximolactams 2 and 36 as inhibitors of the cellobiohydrolases Cel7A and Cel6A from Trichoderma reesei. Cel7A is only weakly inhibited by these compounds. Comparing their inhibitory activity evidences the importance of occupying subsites tl and +2. We results strongly suggest that the shape of none of the variants of the lactone-type inhibitor motif embodied by these inhibitors is complementary to the subsite - 1, i.e.,analogous to the transition state. Cel6A is rather strongly inhibited by the cellobiose analogues 20, 23, and 32, and by the cellotriose analogue 27. Their relative inhibitory activities evidence that binding at subsite -2 depends upon the shape of the moiety occupying subsite - 1. There is only a small difference between the inhibition by the hydroximolactams 20 and 23, which may be (partially) protonated by the catalytic acid of either anti- or syn-protonating glycosidases, and the imidazole 32, which can only be protonated by anti-protonating glycosidases. The results strongly suggest that shape requirements must be met by glycosidase inhibitors before they can be used to characterize the proton trajectory of glycosidases.