Synthesis of new 3-alkoxy-7-amino-4-chloro-isocoumarin derivatives as new β-amyloid peptide production inhibitors and their activities on various classes of protease
摘要:
A series of new 7-substituted-4-chloro-3-alkoxy isocoumarin derivatives were synthesized and evaluated as inhibitors of representative classes of proteases: serine protease (alpha-chymotrypsin, trypsin), cysteine protease (Caspase-3), and aspartyl protease (HIV-protease), 20S proteasome and also as inhibitors of amyloid peptide gamma-secretase-mediated production. Protease inhibition selectivity is directly related to the structure of the substituent at the 7-position of the isocoumarin nucleus. 7-Nitro-isocoumarin derivatives (4c, 4d 4f) are potent alpha-chymotrypsin inhibitors but slightly active or inactive on HIV-protease, as well as on cysteine protease. In contrast.. only derivatives bearing a free amino (5d, 5f) or a substituted amino group (6f) at the 7-position of the isocoumarin nucleus, were found weakly active or inactive on alpha-chymotrypsin, trypsin, Caspase-3 and HIV-protease, but prevent gamma-secretase-mediated production of Abeta 40/42 amyloid peptides, which is known to be involved in Alzheimer's disease. Moreover, the most active compounds on beta-amyloid peptide production [JLK6 (5d), JLK2 (5f) and JLK7 (6f)] show only weak or moderate inhibitory activity on the 20S proteasome. The obtained results suggest that the described new isocoumarin analogues could be of interest, since compounds like JLK6 (5d), JLK2 (5f) and JLK7 (6f) can be considered as possible hits for the development of new agents directed towards Alzheimer's disease. (C) 2003 Elsevier Science Ltd. All rights reserved.
Synthesis of new 3-alkoxy-7-amino-4-chloro-isocoumarin derivatives as new β-amyloid peptide production inhibitors and their activities on various classes of protease
摘要:
A series of new 7-substituted-4-chloro-3-alkoxy isocoumarin derivatives were synthesized and evaluated as inhibitors of representative classes of proteases: serine protease (alpha-chymotrypsin, trypsin), cysteine protease (Caspase-3), and aspartyl protease (HIV-protease), 20S proteasome and also as inhibitors of amyloid peptide gamma-secretase-mediated production. Protease inhibition selectivity is directly related to the structure of the substituent at the 7-position of the isocoumarin nucleus. 7-Nitro-isocoumarin derivatives (4c, 4d 4f) are potent alpha-chymotrypsin inhibitors but slightly active or inactive on HIV-protease, as well as on cysteine protease. In contrast.. only derivatives bearing a free amino (5d, 5f) or a substituted amino group (6f) at the 7-position of the isocoumarin nucleus, were found weakly active or inactive on alpha-chymotrypsin, trypsin, Caspase-3 and HIV-protease, but prevent gamma-secretase-mediated production of Abeta 40/42 amyloid peptides, which is known to be involved in Alzheimer's disease. Moreover, the most active compounds on beta-amyloid peptide production [JLK6 (5d), JLK2 (5f) and JLK7 (6f)] show only weak or moderate inhibitory activity on the 20S proteasome. The obtained results suggest that the described new isocoumarin analogues could be of interest, since compounds like JLK6 (5d), JLK2 (5f) and JLK7 (6f) can be considered as possible hits for the development of new agents directed towards Alzheimer's disease. (C) 2003 Elsevier Science Ltd. All rights reserved.
Effect of the 7-amino substituent on the inhibitory potency of mechanism-based isocoumarin inhibitors for porcine pancreatic and human neutrophil elastases: a 1.85-.ANG. x-ray structure of the complex between porcine pancreatic elastase and 7-[(N-tosylphenylalanyl)amino]-4-chloro-3-methoxyisocoumarin
作者:Maria A. Hernandez、James C. Powers、Jan Glinski、Jozef Oleksyszyn、J. Vijayalakshmi、Edgar F. Meyer
DOI:10.1021/jm00084a018
日期:1992.3
A series of new acyl, urea, and carbonate derivatives of 7-amino-4-chloro-3-methoxyisocoumarin were synthesized and evaluated as irreversible inhibitors of human neutrophil elastase (HNE) and porcine pancreatic elastase (PPE). Inhibition of HNE is directly related to the hydrophobicity of the substituent on the 7-amino group. The N-Tos-Phe derivative (19) is the best HNE inhibitor with a second-order
detect their target proteases in a proteome background in a sensitive manner (down to 0.007% of total protein). Furthermore, we show activity-dependent and selective labeling of endogenous proteases in a tissue proteome. These ICs therefore represent a valuable extension to already existing ABPs for serineproteases and may be instrumental in future elucidation of serineprotease functions.
A fundamentally newreagent space has been discovered for the Castagnoli-Cushman reaction. Cyclic anhydride has been successfully replaced with CDI-activated monoesters of homophthalic acid allowing direct preparation of tetrahydroisoquinolonic esters. Mechanistic studies suggested a new reaction pathway not involving any previously described alkoxyisocoumarines.
Lactone Enolates of Isochroman-3-ones and 2-Coumaranones: Quantification of Their Nucleophilicity in DMSO and Conjugate Additions to Chalcones
作者:Mohammad Sadeq Mousavi、Antonia Di Mola、Giovanni Pierri、Consiglia Tedesco、Magenta J. Hensinger、Aijia Sun、Yilan Wang、Peter Mayer、Armin R. Ofial、Antonio Massa
DOI:10.1021/acs.joc.4c00277
日期:2024.5.17
Owing to stereoelectronic effects, lactones often deviate in reactivity from their open-chain ester analogues as demonstrated by the CH acidity (in DMSO) of 3-isochromanone (pKa = 18.8) and 2-coumaranone (pKa = 13.5), which is higher than that of ethyl phenylacetate (pKa = 22.6). We have now characterized the reactivity of the lactone enolates derived from 3-isochromanone and 2-coumaranone by following
由于立体电子效应,内酯的反应性通常与其开链酯类似物不同,如 3-异色满酮 (p Ka = 18.8) 和 2-香豆酮 (p Ka = 13.5 )的 CH 酸度(在 DMSO 中)所证明的那样,高于苯乙酸乙酯 (p K a = 22.6)。现在,我们通过跟踪 3-异苯并二氢吡喃酮和 2-香豆酮衍生的内酯烯醇化物与对醌甲基化物和亚芳基丙二酸酯(参考亲电子试剂)在 20 °C 下在 DMSO 中的迈克尔反应动力学,表征了它们的反应性。通过 Mayr-Patz 方程 lg k 2 = s N ( N + E ) 对实验确定的二阶速率常数k 2进行评估,提供了内酯烯醇化物的亲核性参数N (和s N )。通过将它们在迈尔亲核性尺度上的位置定位,它们的亲电反应伙伴的范围变得可预测,并且我们展示了一种新的催化方法,用于在甲苯中的相转移条件下内酯烯醇化物与查尔酮的一系列碳-碳键形成反应。
Further characterization of a putative serine protease contributing to the γ-secretase cleavage of β-amyloid precursor protein
The 3-alkoxy-7-amino-4-chloro-isocoumarins JLK-6 and JLK-2 have been shown to markedly reduce the production of Amyloid beta-peptide (A beta) by Amyloid-beta Precursor Protein (APP) expressing HEK293 cells by affecting the gamma-secretase cleavage of APP, with no effect on the cleavage of the Notch receptor. This suggested that these compounds do not directly inhibit the presenilin-dependent gamma-secretase complex but more likely interfere with an upstream target involved in gamma-secretase-associated pathway. The mechanism of action of these compounds is unknown and there are high fundamental and therapeutical interests to unravel their target. Isocoumarin compounds were previously shown to behave as potent mechanism-based irreversible inhibitors of serine proteases, suggesting that the JLK-directed target could belong to such enzyme family. To get further insight into structure-activity relationships and to develop more potent isocoumarin derivatives, we have synthesized and evaluated a series of isocoumarin analogues with modifications at positions 3, 4 and 7. In particular, the 7-amino group was substituted with either acyl, urethane, alkyl or aryl groups, which could represent additional interaction sites. Altogether, the results highlighted the essential integrity of the 3-alkoxy-7-amino-4-chloro-isocoumarin scaffold for A beta-lowering activity and supported the involvement of a seri ne protease, or may be more generally, a serine hydrolase. The newly reported 7-N-alkyl series produced the most active compounds with an IC50 between 10 and 30 mu M. Finally, we also explored peptide boronates, a series of reversible serine protease inhibitors, previously shown to also lower cellular A beta production. The presented data suggested they could act on the same target or interfere with the same pathway as isocoumarins derivatives. (C) 2012 Elsevier Ltd. All rights reserved.