4720-29-0Relevant articles and documents
Synthesis of N-(2-guanidinoethyl)-tetrahydrothieno[3,2-c]azepine, N-(2- guanidinoethyl)-tetrahydro-2-benzazepine and N-(2-guanidinoethyl)-tetrahydro- 1-benzazepine as analogous to antihypertensive agent guanetidine
Ravina,Ramos,Masaguer,Mera
, p. 321 - 332 (1994)
N-(2-guanidinoethyl)-tetrahydrothieno[3,2-c]azepine 10a, N-(2- guanidinoethyl)-tetrahydro-2-benzazepine 10b and N-(2-guanidinoethyl)- tetrahydro-1-benzazepine 10c analogous of the antihypertensive agent Guanetidine were prepared by cyanomethylation of the corresponding azepines, reduction and subsequent guanilation of the resulting aminoethyl derivatives. These compounds were evaluated for antihypertensive activity in SHR rats but no significant activity was observed.
Two stepwise synthetic routes toward a hetero[4]rotaxane
Luo, Qian-Fu,Zhu, Lan,Rao, Si-Jia,Li, Hong,Miao, Qi,Qu, Da-Hui
, p. 4704 - 4709 (2015)
Heterorotaxanes have been emerging as an important class of mechanically interlocked molecules and have attracted much attention in recent years. Driven by the distinguishable host-guest interactions between crown ether macrocycles and ammonium with different sizes, a novel hetero[4]rotaxane was successfully prepared by employing the combination of copper-catalyzed "click" reaction and P(n-Bu)3-catalyzed esterification reaction as stoppering reactions. The hetero[4]rotaxane contains an interlocked species in which a dibenzo[24]crown-8 ring threaded by a dibenzylammonium-containing component with two benzo[21]crown-7 macrocycles at both ends to act as stoppers, and each of the two benzo[21]crown-7 rings is also threaded with a benzylalkylammonium unit to form the second interlocked species. The hetero[4]rotaxane was prepared through two different stepwise synthetic routes, and the complicated chemical structure of the hetero[4]rotaxane was well-characterized by 1H NMR spectroscopy and high-resolution electrospray ionization (HR-ESI) mass spectrometry. The investigation shows that the construction of complicated topological heterorotaxane can be achieved via distinct approaches with high efficiencies, which may provide a foundation for the construction of more sophisticated heterorotaxane systems or functional supermolecules.
An Alternative Approach to the Hydrated Imidazoline Ring Expansion (HIRE) of Diarene-Fused [1.4]Oxazepines
Grintsevich, Sergey,Sapegin, Alexander,Reutskaya, Elena,Peintner, Stefan,Erdélyi, Máté,Krasavin, Mikhail
, p. 5664 - 5676 (2020/07/21)
A four-step approach to the “hydrated imidazoline ring expansion” (HIRE) is presented. In most cases, the ring expansion was the sole process. However, for the first time, an alternative course of the hydrated imidazoline evolution was discovered which gave N-aminoethyl derivatives. These can, in principle, be converted into the target HIRE products under sufficiently forcing conditions. The approach offers improved flexibility with respect to the peripheral substituents and is also applicable to the synthesis of eleven-membered lactams. We observed that the latter can exist in two stable isomeric forms due to lactam–amide bond isomerization. The latter finding further demonstrates the value of medium-sized rings as multiple-conformer probes for biological target interrogation.
Iron-Catalyzed Anti-Markovnikov Hydroamination and Hydroamidation of Allylic Alcohols
Ma, Wei,Zhang, Xiaohui,Fan, Juan,Liu, Yuxuan,Tang, Weijun,Xue, Dong,Li, Chaoqun,Xiao, Jianliang,Wang, Chao
supporting information, p. 13506 - 13515 (2019/09/09)
Hydroamination allows for the direct access to synthetically important amines. Controlling the selectivity of the reaction with efficient, widely applicable, and economic catalysts remains challenging, however. This paper reports an iron-catalyzed formal anti-Markovnikov hydroamination and hydroamidation of allylic alcohols, which yields γ-amino and γ-amido alcohols, respectively. Homoallylic alcohol is also feasible. The catalytic system, consisting of a pincer Fe-PNP complex (1-4 mol %), a weak base, and a nonpolar solvent, features exclusive anti-Markovnikov selectivity, broad substrate scope (>70 examples), and good functional group tolerance. The reaction could be performed at gram scale and applied to the synthesis of drug molecules and heterocyclic compounds. When chiral substrates are used, the stereochemistry and enantiomeric excess are retained. Further application of the chemistry is seen in the functionalization of amino acids, natural products, and existing drugs. Mechanistic studies suggest that the reaction proceeds via two cooperating catalytic cycles, with the iron complex catalyzing a dehydrogenation/hydrogenation process while the amine substrate acts as an organocatalyst for the Michael addition step.
