开发了一种高效的催化对映选择性分子内Povarov反应,以伯苯胺作为2-氮杂二烯的前体。无需柱色谱,即可获得各种成角度的稠合氮杂环化合物,高产率至优异产率,非对映异构体和对映异构体选择性高(dr> 99:1,最高可达er er 99:1)。此外,催化剂负载量可以降低至1mol%,并且所获得的氮杂环化合物可以用作进一步转化以产生额外的分子多样性的关键中间体。
Construction of 2,3-disubstituted benzo[<i>b</i>]thieno[2,3-<i>d</i>]thiophenes and benzo[4,5]selenopheno[3,2-<i>b</i>]thiophenes using the Fiesselmann thiophene synthesis
作者:Roman A. Irgashev、Nadezhda S. Demina、Gennady L. Rusinov
DOI:10.1039/d0ob00300j
日期:——
nzo[b]thiophenes. The latter ketones were treated either with methyl thioglycolate in the presence of DBU and calcium oxide powder or successively with sodium sulfide, an alkylating agent, containing methylene active component, and also DBU and calcium oxide, to form the desired benzo[b]thieno[2,3-d]thiophenederivatives. In addition, similar benzo[4,5]selenopheno[3,2-b]thiophenederivatives were prepared
TsNBr2 promoted decarboxylative bromination of α,β-unsaturated carboxylic acids
作者:Debojit Hazarika、Prodeep Phukan
DOI:10.1016/j.tetlet.2018.11.041
日期:2018.12
A rapid process for decarboxylative bromination of α,β-unsaturatedcarboxylicacids have been developed using N,N-dibromo-p-toluenesulfonamide (TsNBr2). Treatment of cinnamic acids with TsNBr2 in presence of potassium carbonate in acetonitrile produces corresponding β-bromostyrenes at room temperature. Exclusive formation of (E)-β-bromostyrenes was observed in a stereoselective manner within a very
1,2,3-triazolo[4,5-d]pyrimidines as P2T receptor antagonists
申请人:AstraZeneca UK Limited
公开号:US06251910B1
公开(公告)日:2001-06-26
Compounds of formula having the following stereochemistry
wherein R, R1, R2, R3 and R4 are as defined in the specification. The compounds are useful as P2T receptor antagonists.
Design, synthesis, and structure activity relationship analysis of new betulinic acid derivatives as potent HIV inhibitors
作者:Yu Zhao、Chin-Ho Chen、Susan L. Morris-Natschke、Kuo-Hsiung Lee
DOI:10.1016/j.ejmech.2021.113287
日期:2021.4
and evaluated for anti-HIV-1 replication activity against HIV-1NL4-3 infected MT-4 cell lines. Five known and 21 newderivatives were as or more potent than 3 (EC50 0.065 μM), while eight newderivatives were as or more potent than 4 (EC50 0.019 μM). These derivatives feature expanded structural diversity and chemical space that may improve the antiviral activity and address the growing resistance crisis
Ligand Dependent Switch from RXR Homo- to RXR-NURR1 Heterodimerization
作者:Marcel Scheepstra、Sebastian A. Andrei、Rens M. J. M. de Vries、Femke A. Meijer、Jian-Nong Ma、Ethan S. Burstein、Roger Olsson、Christian Ottmann、Lech-Gustav Milroy、Luc Brunsveld
DOI:10.1021/acschemneuro.7b00216
日期:2017.9.20
Retinoid X receptors (RXRs) play key roles in many physiological processes in both the periphery and central nervous system. In addition, RXRs form heterodimers with other nuclear receptors to exert their physiological effects. The nuclear receptor related 1 protein (NURR1) is particularly interesting because of its role in promoting differentiation and survival of dopamine neurons. However, only a small number of RXR-heterodimer selective modulators are available, with limited chemical diversity. This work describes the synthesis, biochemical evaluation, and structural elucidation of a novel series of RXR ligands with strongly biased interactions with RXRa-NURRI heterodimers. Targeted modifications to the small molecule biaryl scaffold caused local RXRa side -chain disturbances and displacement of secondary structural elements upon ligand binding. This resulted in the repositioning of protein helices in the heterodimer interface of RXRa, alterations in homo- versus heterodimer formation, and modulation of activation function 2 (AF2). The data provide a rationale for the design of RXR ligands consisting of a highly conserved hydrophilic region, strongly contributing to the ligand affinity, and a variable hydrophobic region, which efficiently probes the effects of structural changes at the level of the ligand on co -regulator recruitment or the RXRa-NURRI dimerization interface.