Donor cyclopropanes in synthesis: utilising silylmethylcyclopropanes to prepare 2,5-disubstituted tetrahydrofurans
作者:Jonathan Dunn、Majid Motevalli、Adrian P. Dobbs
DOI:10.1016/j.tetlet.2011.10.091
日期:2011.12
The use of donor-only silylmethylcyclopropanes in the Lewis acid promoted reaction with aldehydes to generate 2,5-disubstitutedtetrahydrofurans is described. The diastereoselectivity obtained in the product is very much dependent upon the temperature of the reaction.
[EN] OPSIN-BINDING LIGANDS, COMPOSITIONS AND METHODS OF USE<br/>[FR] LIGANDS DE LIAISON À UNE OPSINE, COMPOSITIONS ET PROCÉDÉS D'UTILISATION
申请人:BIKAM PHARMACEUTICALS INC
公开号:WO2013058809A1
公开(公告)日:2013-04-25
Compounds are disclosed that are useful for treating ophthalmic conditions caused by or related to production of toxic visual cycle products that accumulate in the eye, such as dry adult macular degeneration, as well as conditions caused by or related to the misfolding of mutant opsin proteins and/or the mis-localization of opsin proteins. Compositions of these compounds alone or in combination with other therapeutic agents are also described, along with therapeutic methods of using such compounds and/or compositions. Methods of synthesizing such agents are also disclosed.
amount of InCl3 and aceticanhydride remarkably promotes the Knoevenagel condensation of a variety of aldehydes and activated methylene compounds. This catalytic system accommodates aromatic aldehydes containing a variety of electron-donating and -withdrawing groups, heteroaromatic aldehydes, conjugate aldehydes, and aliphatic aldehydes. Central to successfully driving the condensation series is the formation
Low-temperature photooxygenation of coelenterate luciferin analog synthesis and proof of 1,2-dioxetanone as luminescence intermediate
作者:Ken Usami、Minoru Isobe
DOI:10.1016/0040-4020(96)00699-0
日期:1996.9
13C-enriched coelenterate luciferin analogs were photooxygenated at −78°C to form two peroxidic products as luminescent intermediates. Structures of these unstableintermediates were deduced by means of 13C NMR spectra at low temperatures using substrates enriched at three sites by 13C. Photooxygenation in a mixture of CF3CD2OD and CD3OD as highly protic solvents afforded the dioxetanone and 2-hydroperoxide. These
在2-位具有叔丁基的腔肠荧光素类似物适合在各种条件下进行化学发光研究。在低温(-78°C)下对类似物进行光氧化可得到发光中间体,该发光中间体通过用PPh 3还原而被证明是过氧化物,从而导致发光能力下降。为了通过13 C NMR阐明这些积累的发光中间体的结构,在3,7-二氢咪唑并[1,2-a]吡嗪-3-酮的2、3和5位合成了三个13 C富集的类似物。骨架具有99%的富集和位点特异性。这13个将富C的腔肠荧光素类似物在-78°C进行光氧化,以形成两种过氧化物产物,作为发光中间体。这些不稳定的中间体的结构用的手段推断13 C NMR光谱在使用在三个位点被富集的底物低的温度13 ℃。在光氧化CF的混合物3 CD 2 OD和CD 3 OD为高度的质子溶剂,得到dioxetanone和2 -氢过氧化物。在含有酸或碱的二甘醇二甲醚(DGM)中稀释到10 -5 M后,这两种过氧化物在不同的温度下分别在400
Polystyrene or Magnetic Nanoparticles as Support in Enantioselective Organocatalysis? A Case Study in Friedel–Crafts Chemistry
作者:Sara Ranjbar、Paola Riente、Carles Rodríguez-Escrich、Jagjit Yadav、Kishore Ramineni、Miquel A. Pericàs
DOI:10.1021/acs.orglett.6b00462
日期:2016.4.1
successfully applied to the asymmetric Friedel–Crafts alkylation of indoles with α,β-unsaturated aldehydes. While both catalytic systems can be easily recovered and admit repeated recycling, the polystyrene-based catalyst shows higher stability and provides better stereoselectivities.
第一次描述了第二代MacMillan咪唑啉丁4 -one的异构化版本。通过铜催化的炔-叠氮化物环加成(CuAAC)反应,这种通用的有机催化剂已负载在1%DVB Merrifield树脂和Fe 3 O 4磁性纳米颗粒上。所得的催化材料已成功地用于吲哚与α,β-不饱和醛的不对称Friedel-Crafts烷基化反应。虽然两个催化体系都可以轻松回收并允许重复循环,但聚苯乙烯基催化剂显示出更高的稳定性并提供了更好的立体选择性。