Triplet phenacylimidazoliums-catalyzed photocycloaddition of 1,4-dihydropyridines: An experimental and theoretical study
摘要:
The photocycloadditions of 1,4-dihydropyridines (DHPs) were achieved by using phenacylimidazoliums (Plms) as photosensitizers. Irradiation of DHPs 3a-g in the presence of Plms 1a-e and 2 performed an efficient formation of 3,9-diazatetraasteranes in shorter times under a lower power lamp. The mechanism of photocycloaddition catalyzed by Plm was studied by laser flash photolysis and theoretical OFT computation. These time-resolved results showed that the triplet excited states of Plms were generated with high efficiency and detected by their characteristic ultraviolet absorptions, which were quenched by DHP at almost diffusion controlled rate. Theoretical studies suggest that Plm is involved in the photocycloaddition process through the (3)(DHP center dot center dot center dot Plm)* triplet complexes and assists the stabilization of intermediates. All subsequent steps are predicted to be favorable and exothermic, leading to the cage dimers. (C) 2012 Elsevier B.V. All rights reserved.
Biological evaluation of 4-aryl-1,4-dihydropyridines as VEGFR-2 kinase inhibitors
摘要:
Vascular endothelial growth factor-2 receptor (VEGFR-2) kinase is a promising target for the development of novel anticancer drugs. Molecular docking modeling was performed on a series of 4-aryl-1,4-dihydropyridines derivatives to evaluate the structural basis for VEGFR-2 inhibitory activity. Some 4-aryl-1,4-dihydropyridines were synthesized in the reaction of aromatic aldehydes and ethyl propiolate with anilines in acetic acid. The biological activities were evaluated against the cells A549, A431 and Hep-G2. The results indicated that 4-aryl-1,4-dihydropyridines could be the promising potential VEGFR-2 inhibitors.
Design, Synthesis and Biological Evaluation of 3,9-diazatetraasteranes as Novel Matrilysin Inhibitors
作者:Yanlan Liu、Hongbo Tan、Hong Yan、Xiuqing Song
DOI:10.1111/cbdd.12185
日期:2013.11
Matrilysin is an ideal biological target to develop novel inhibitors because it is overexpressed in malignant tumour cells. A series of 3,9‐diazatetraasteranes was designed as inhibitors of matrilysin, which was an ideal biological target because it is responsible for aggressive malignant phenotypes and poor prognoses implicated in many cancers. Docking simulation supported the initial pharmacophore hypothesis and suggested a common interaction mechanism of 3,9‐diazatetraasteranes with the catalytic site of matrilysin. The 3,9‐diazatetraasteranes were synthesized by the photocyclization of 4‐aryl‐1,4‐dihydropyridines, and their structures were determined using 1H NMR, 13C NMR and MS. The inhibitory activities of these compounds on matrilysin were investigated in vitro using an MTT assay in A549 (small cell lung cancer) cells. The results show that the 3,9‐diazatetraasteranes can inhibit the growth of A549 tumour cells. The best IC50 value is approximately 50 μm. This result indicates that 3,9‐diazatetraasteranes will be useful pharmacological tools for the investigation of matrilysin inhibitors.
Synthesis and Biological Activity of 3,9-Diazatetraasteranes as Novel EGFR Tyrosine Kinase Inhibitors
作者:Li Mao、Nana Tian、Chaochun Wei、Hongjun Wang、Hong Yan