Copper-catalysed oxidative C–H/N–H cross-coupling between formamides and amides through chelation-assisted N–H activation
作者:Xiaoyu Li、Bijin Li、Jingsong You、Jingbo Lan
DOI:10.1039/c3ob40094h
日期:——
A copper-catalysed oxidative CâH/NâH cross-coupling between formamides and amides through chelation-assisted NâH activation has been developed for the preparation of various multi-substituted ureas.
Solvent- and halide-free synthesis of pyridine-2-yl substituted ureas through facile C–H functionalization of pyridine N-oxides
作者:Valentin A. Rassadin、Dmitry P. Zimin、Gulnara Z. Raskil'dina、Alexander Yu. Ivanov、Vadim P. Boyarskiy、Semen S. Zlotskii、Vadim Yu. Kukushkin
DOI:10.1039/c6gc02556k
日期:——
A novel solvent- and halide-free atom-economic synthesis of practically useful pyridine-2-yl substituted ureas utilizes easily accessible or commercially available pyridine N-oxides (PyO) and dialkylcyanamides. The observed C-H functionalization of PyO...
Reaction of coordinated isocyanides with substituted N-(2-pyridyl) ureas as a route to new cyclometallated Pd(II) complexes
作者:Kirill K. Geyl、Sergey V. Baykov、Svetlana O. Kasatkina、Polina Yu. Savko、Vadim P. Boyarskiy
DOI:10.1016/j.jorganchem.2022.122518
日期:2022.12
Substituted N-(pyridin-2-yl) ureas or carbamates act as polynucleophiles upon the reaction with palladium(II) bis(isocyanide) complexes at RT to give metallacycles containing azaheterocyclic and urea fragments. Nine new C,N-chelate deprotonated diaminocarbene palladium(II) complexes were synthesized by coupling substituted N-(2-pyridyl)ureas and coordinated isocyanides. The obtained yellow or green-yellow
取代的N- (吡啶-2-基) 脲或氨基甲酸酯在室温下与双(异氰化物) 钯 (II) 配合物反应时充当多亲核试剂,得到含有氮杂杂环和脲片段的金属环。通过偶联取代的N- (2-吡啶基)脲和配位异氰化物,合成了九种新的C,N-螯合去质子化二氨基卡宾钯(II)配合物。获得的黄色或绿黄色物种通过高分辨率质谱和一维(1 H, 13C) 核磁共振光谱。通过单晶 X 射线衍射 (XRD) 阐明了六种固态配合物的结构。这种在温和条件下制备 C^N-环金属化钯 (II) 配合物的通用且方便的方法为靶向合成结合了金属环和母体氮杂杂环的化学、生物和光物理性质的多功能有机金属化合物开辟了道路。
Intramolecular Hydrogen Bonding in Medicinal Chemistry
作者:Bernd Kuhn、Peter Mohr、Martin Stahl
DOI:10.1021/jm100087s
日期:2010.3.25
The formation of intramolecular hydrogen bonds has a very pronounced effect on molecular structure and properties. We study both aspects in detail with the aim of enabling a more rational use of this class of interactions in medicinal chemistry. On the basis of exhaustive searches in crystal structure databases, we derive propensities for intramolecular hydrogen bond formation of five- to eight-membered ring systems of relevance in drug discovery. A number of motifs, several of which arc clearly underutilized in drug discovery, are analyzed in more detail by comparing small molecule and protein ligand X-ray structures. To investigate effects on physicochemical properties, sets of closely related structures with and without the ability to form intramolecular hydrogen bonds were designed, synthesized, and characterized with respect to membrane permeability, water solubility, and lipophilicity. We find that changes in these properties depend on a subtle balance between the strength of the hydrogen bond interaction, geometry of the newly formed ring system, and the relative energies of the open and closed conformations in polar and unpolar environments. A number of general guidelines for medicinal chemists emerge from this study.
Synthesis and Properties of N,N′-Disubstituted Ureas Containing Adamantane and Pyridine (Quinoline) Fragments
作者:S. O. Baykova、S. V. Baykov、A. A. Petrov、V. V. Burmistrov、V. P. Boyarskiy