A synthetically useful approach for the synthesis of functionalized α, α‐disubstituted α‐amino acid derivatives via palladium‐catalyzed 1,7 addition of readily available aldimine esters to vinylcyclopropanes is reported. This methodology was operated under mild conditions, affording α‐allylic α‐amino esters in good to excellent yields and excellent regio‐ and stereoselectivity. This transformation
reported compounds are potent hA3 adenosine receptor antagonists and some of them exhibited high selectivity against the other adenosine receptors. The main structural terms of ligand recognition and selectivity were disclosed by molecular modelling studies. Molecular docking results led to the characterization of an alternative binding mode for antagonists at the orthosteric binding site of the hA3 adenosine
A 3腺苷受体被发现在不同的病理状态中起作用,例如青光眼、肾纤维化、神经性疼痛和癌症。因此,重要的是利用任何有助于研究这些条件的分子工具。在本研究中,我们继续寻找有效的 A 3腺苷受体配体,这些配体可以连续与其他分子偶联,目的是获得更有效的(例如变构配体偶联)或可检测的配体(例如荧光分子或生物素偶联)。具体而言,在吡唑并[4,3 - e ]-1,2,4-三唑并[1,5- c ]的5位引入了不同的氨基酯部分。]嘧啶核。酯官能化代表后续缀合的候选。所有报道的化合物都是有效的 hA 3腺苷受体拮抗剂,其中一些对其他腺苷受体表现出高选择性。分子模型研究揭示了配体识别和选择性的主要结构术语。分子对接结果导致在 hA 3腺苷受体的正构结合位点处对拮抗剂的替代结合模式进行表征,通过经典分子动力学模拟进行评估和评估。
2-(Ethoxycarbonylmethyl)-1H-naphtho[1,8-de]-1,2,3-triazine anion: a new glycine enolate equivalent
The titled triazine can be alkylated with LDA and a variety of alkyl halides: subsequent reduction with aluminium amalgam cleaves the naphthotriazine moiety to afford substituted α amino acids in excellent overall yields; the sequence defines a novel methodology that can be applied under non-acidic and largely non-aqueous conditions.
The invention provides unsaturated phosphonates of Formula I or a tautomer or pharmaceutically accepatble salt thereof, as described herein, as well as pharmaceutical compositions comprising the compounds, and therapeutic methods comprising administering the compounds. The compounds have anti-viral properties and are useful for treating viral infections (e.g. HCV) in animals (e.g. humans).
Efficient Synthesis of <font>α</font>-Substituted Amino Acid Ester: Alkylation and Hydrogenation Removal of Schiff's Base Protecting Group
作者:Aslam M. Ansari、Sydney O. Ugwu
DOI:10.1080/00397910802138611
日期:2008.6.27
Abstract A general and efficient syntheticroute to α-aminoacids by alkylation of the sodium salt of Schiff base ester 1 has been described previously. The α-substituted ethyl glycinates 4a–g are prepared in excellent yield by a two-step sequence involving regioselective alkylation of the anionic glycine synthon 2 with various alkyl halides, followed by purification of the alkylated Schiff base on