70067-45-7Relevant articles and documents
Coordination polymers derived from a flexible bis(pyridylurea) ligand: Conformational change of the ligand and structural diversity of the complexes
Hao, Yongjing,Wu, Biao,Li, Shaoguang,Jia, Chuandong,Huang, Xiaojuan,Yang, Xiao-Juan
, p. 215 - 222 (2011)
The assembly of a bis(pyridylurea) ligand, N,N′-ethane-1,2-diylbis(3- pyridin-4-ylurea) (L), with Zn(AcO)2, CdCl2, CdSO 4 or CuSO4 led to four coordination polymers, {[Zn(AcO)2L]·H2O·CH3OH} n (1), {[CdCl2L2]·2DMF}n (2), {[CdSO4L(H2O)3]·3H2O} n (3), and {[CuSO4L(H2O)2] ·2H2O}n (4). Compound 1 is an infinite 1D zigzag chain with alternate Zn(AcO)2 units and L molecules. The cadmium(ii) dichloro complex 2 features a corrugated sheet structure with a (4,4) net topology, while the sulfato complex 3 shows a unique 1O/2U interwoven 3D structure assembled from zigzag chains. The copper(ii) complex 4 is an exceptional diamondoid network with an unusual 12-fold [6 + 6] interpenetration mode. Interestingly, the ligand shows the expected flexibility in the formation of the coordination polymers. In 1, 3 and 4, the central ethylene spacer adopts the anti conformations and is roughly linear, whereas in 2 it assumes a gauche form and exists as a V-shaped linker. The structural variation of these coordination polymers as well as the conformational change of the ligand in the presence of different counter anions and metal ions is discussed.
Making and breaking of gels: Stimuli-responsive properties of bis(pyridyl-n-oxide urea) gelators
Damodaran, Krishna K.,Ghosh, Dipankar,Jayabhavan, Sreejith Sudhakaran
, (2021/11/01)
The structural modification of existing supramolecular architecture is an efficient strategy to design and synthesize supramolecular gels with tunable and predictable properties. In this work, we have modified bis(pyridyl urea) compounds with different linkers, namely hexylene and butylene, to their corresponding bis(pyridyl-N-oxide urea). The gelation properties of both the parent and the modified compounds were studied, and the results indicated that modification of the 3-pyridyl moieties to the corresponding 3-pyridyl-N-oxides induced hydrogelation. The stability of the parent and modified compounds were evaluated by sol-gel transition temperature (Tgel ) and rheological measurements, and single-crystal X-ray diffraction was used to analyze the solid-state interactions of the gelators. The morphologies of the dried gels were analyzed by scanning electron microscopy (SEM), which revealed that the structural modification did not induce any prominent effect on the gel morphology. The stimuli-responsive behavior of these gels in the presence of salts in DMSO/water was evaluated by rheological experiments, which indicated that the modified compounds displayed enhanced gel strength in most cases. However, the gel network collapsed in the presence of the chloride salts of aluminum(III), zinc(II), copper(II), and cadmium(II). The mechanical strength of the parent gels decreased in the presence of salts, indicating that the structural modification resulted in robust gels in most cases. The modified compounds formed gels below minimum gel concentration in the presence of various salts, indicating salt-induced gelation. These results show the making and breaking ability of the gel network in the presence of external stimuli (salts), which explains the potential of using LMWGs based on N-oxide moieties as stimuli-responsive materials.
S1PR2 inhibitors potently reverse 5-FU resistance by downregulating DPD expression in colorectal cancer
Zhang, Yu-Hang,Luo, Dong-Dong,Wan, Sheng-Biao,Qu, Xian-Jun
, (2020/02/29)
In this study, S1PR2 was reckoned as a brand-new GPCR target for designing inhibitors to reverse 5-FU resistance. Herein a series of pyrrolidine pyrazoles as the S1PR2 inhibitors were designed, synthesized and evaluated for their activities of anti-FU-resistance. Among them, the most promising compound JTE-013, exhibited excellent inhibition on DPD expression and potent anti-FU-resistance activity in various human cancer cell lines, along with the in vivo HCT116DPD cells xenograft model, in which the inhibition rate of 5-FU was greatly increased from 13.01percent–75.87percent. The underlying mechanism was uncovered that JTE-013 demonstrated an anti-FU-resistance activity by blocking S1PR2 internalization to the endoplasmic reticulum (ER), which inhibited the degradation of 5-FU into α-fluoro-β-alanine (FBAL) by downregulating tumoral DPD expression. Overall, JTE-013 could serve as the lead compound for the discovery of new anti-FU-resistance drugs. Significance: This study provides novel insights that S1PR2 inhibitors could sensitize 5-FU therapy in colorectal cancer.