A simple, mild, one-pot tandem method catalyzed by trypsin was developed for the synthesis of 3,4-dihydropyrimidin-2(1 H )-ones by the Biginelli reaction of urea, β-dicarbonyl compounds, and in situ-formed acetaldehyde. Trypsin was found to display dual promiscuous functions to catalyze transesterification and the Biginelli reaction in sequence.
Xiaoqing Wang,Huiyi Chen,Jihui Zhang,Hong Zhou,Xiangying Meng,Na Wang,Yishan Fang,Bo Cui
The detection of Escherichia coli ( E. coli ) is of great significance for the environment and human health. Herein, a photoelectrochemical (PEC) detection strategy based on molecularly imprinted polymers (MIPs) was proposed for the sensitive detection of E. coli . 4,4′,4″-Trinitrotriphenylamine (TPA-NO 2 ) was prepared using a simple nitration reaction. Subsequently, MIP films were polymerized on the surface of TPA-NO 2 using 1,3-dihydrothieno[3,2- d ]pyrimidine-2,4-dione as the functional monomer with the dual functions of specific recognition and sensitization. The linear range was 10–10 8 CFU/mL and the limit of detection was 10 CFU/mL. It showed favorable recoveries in real sample tests of milk, orange juice and tomato. Additionally, the ability of functional monomers to bind excellently with E. coli was verified using molecular docking techniques. This research provided broader possibilities for constructing MIPs-PEC sensors and analyzing the interaction mechanism between E. coli and functional monomers.
Yi Huang,Fengling Liu,Shuhua Ren,Yuanqing Ding,Man Chi,Weiwei Huang,Wenjing Gu,Hewen Qian,Yaxia Yuan,Shurong Hou,Xiabin Chen,Lei Ma
Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal lung disease with an elusive etiology. Aberrant activation of c-Jun N-terminal kinase 1 (JNK1) has been implicated in its pathogenesis. Through a combination of structure-based drug design and structure–activity relationship (SAR) optimization, a series of pyrimidine-2,4-diamine scaffold derivatives have been developed as potent JNK1 inhibitors. Compound E1 was identified with low nanomolar JNK1 inhibitory potency (IC50 = 2.7 nM). The introduction of a dimethylamine side chain has significantly enhanced the ability of E1 to inhibit c-Jun phosphorylation, surpassing the clinical candidate CC-90001. Molecular dynamics simulations revealed a binding free energy of −50.46 kcal/mol for E1. Moreover, E1 displayed satisfactory pharmacokinetic properties, with a bioavailability of 69% in rats. Furthermore, compound E1 exerted significant antifibrotic effects in a bleomycin-induced IPF mouse model and prevented a TGF-β-induced epithelial-to-mesenchymal transition in vitro. These findings position E1 as a promising lead for further drug development targeting IPF.