Structure−Activity Relationship of 4(5)-Aryl-2-amino-1H-imidazoles, N1-Substituted 2-Aminoimidazoles and Imidazo[1,2-a]pyrimidinium Salts as Inhibitors of Biofilm Formation by Salmonella Typhimurium and Pseudomonas aeruginosa
摘要:
A library of 112 4(5)-aryl-2-amino-1H-imidazoles, 4,5-diphenyl-2-amino-1H-imidazoles, and N1-substituted 4(5)-phenyl-2-aminoimidazoles was synthesized and tested for the antagonistic effect against biofilm formation by Salmonella Typhimurium and Pseudomonas aeruginosa. The substitution pattern of the 4(5)phenyl group and the nature of the N1-substituent were found to have a major effect on the biofilm inhibitory activity. The most active compounds of this series were shown to inhibit the biofilm formation at low micromolar concentrations. Furthermore, the influence of 6 imidazo[1,2-a]pyrimidines and 18 imidazo[1,2-a]pyrimidinium salts on the biofilm formation was tested. These compounds are the chemical precursors of the 2-aminoimidazoles in our synthesis pathway. A good correlation was found between the activity of the imidazo[1,2-a]pyrimidinium salts and their corresponding 2-aminoimidazoles, supporting the hypothesis that the imidazo[1,2-a]pyrimidinium salts are possibly cleaved by cellular nucleophiles to form the active 2-aminoimidazoles. However, the imidazo[1,2-a]pyrimidines did not show any biofilm inhibitory activity, indicating that these molecules are not susceptible to in situ degradation to 2-aminoimidazoles. Finally, we demonstrated the lack of biofilm inhibitory activity of an array of 37 2N-substituted 2-aminopyrimidines, which are the chemical precursors of the imidazo[1,2-a]pyrimidinium salts in our synthesis pathway.
Efficient alkylations of amines by alcohols catalyzed by well-defined Co(II) complexes are described that are stabilized by a PCP ligand (N,N′-bis(diisopropylphosphino)-N,N′-dimethyl-1,3-diaminobenzene) based on the 1,3-diaminobenzene scaffold. This reaction is an environmentally benign process implementing inexpensive, earth-abundant nonprecious metal catalysts and is based on the acceptorless alcohol
Palladium-catalyzed remote C–H functionalization of 2-aminopyrimidines
作者:Animesh Das、Akash Jana、Biplab Maji
DOI:10.1039/d0cc00575d
日期:——
A straightforward strategy was developed for the arylation and olefination at the C5-position of the N-(alkyl)pyrimidin-2-amine core with readily available aryl halides and alkenes, respectively. This approach was highly regioselective, and the transformation was achieved based on two different (Pd(ii)/Pd(iv)) and (Pd(0)/Pd(ii)) catalytic cycles.
Ag(i) complexes with alkylidene-bis(2-aminopyrimidines) as building units for discrete metallomacrocyclic frames. A structural and solution study
作者:Angel García-Raso、Juan J. Fiol、Andrés Tasada、Francisca M. Albertí、Elies Molins、Manuel G. Basallote、María A. Máñez、María J. Fernández-Trujillo、David Sánchez
DOI:10.1039/b508260a
日期:——
Alkylidene-bis(2-aminopyrimidines)
(pyr2Cx, x
= 2–5) are useful ligands to interact with Ag(I) yielding discrete metallocycles. Crystal structures of the [(pyr2C2)Ag(NO3)]2 and [(H-pyr2C4)Ag(NO3)2]2 have been isolated where each macrocyclic moiety interacts with their surroundings through weak interactions, yielding 3D discrete structures, On the other hand, the solution study shows that the equilibrium constants for the formation of Ag(pyr2Cx)+ complexes are higher than the literature values for Ag(I) complexes with single pyrimidines, although the differences could be explained by invoking the solid-state structures of the Ag(I)–pyr2Cx complexes.
烯叉双(2-氨基嘧啶)(pyr2Cx, x = 2–5)是有用的配体,能与Ag(I)生成离散的金属环。分离得到了[(pyr2C2)Ag(NO3)]2和[(H-pyr2C4)Ag( )2]2的晶体结构,其中每个大环部分都通过弱相互作用与其周围环境相互作用,形成三维离散结构。另一方面,溶液研究显示,Ag(pyr2Cx)+配合物的形成平衡常数高于已知文献中单嘧啶Ag(I)配合物的值,尽管这种差异可以通过考虑Ag(I)-pyr2Cx配合物的固态结构来解释。
Air Stable Iron(II) PNP Pincer Complexes as Efficient Catalysts for the Selective Alkylation of Amines with Alcohols
A series of well‐defined iron(II) complexes of the types [Fe(PNP)Br2] and [Fe(PNP)(CO)Br2] with PNPpincer ligands based on triazine and pyridine backbones were prepared and fully characterized. These complexes were tested as catalysts for the alkylation of amines by alcohols. The high‐spin complexes [Fe(PNP)Br2] are catalytically inactive. The low‐spin complexes [Fe(PNP)(CO)Br2] bearing a carbonyl