从市售的 (+)-胡芦巴酮中以 12% 的总产率实现了石杉碱 H 的第一个不对称全合成。该合成的关键步骤包括带有甲硅烷基烯醇醚的吡咯的高度非对映选择性 Mukaiyama-Michael 加成反应和分子内 S N 2 环化反应,碘化吡咯作为形成九元环的有效亲核试剂。结果,建立了石杉碱H的相对和绝对立体化学。
The internal heavy-atom effect on 3-phenylselanyl and 3-phenyltellanyl BODIPY derivatives studied by transient absorption spectroscopy
作者:Jamaludin Al Anshori、Tomáš Slanina、Eduardo Palao、Petr Klán
DOI:10.1039/c5pp00366k
日期:2016.2
containing analogues as well as an unsubstituted BODIPY derivative. The fluorescence quantum yields were found to decrease, whereas the intersystem crossing quantum yields (PhiISC), determined by transientspectroscopy, increased in the order of the H --> Cl --> Se/I --> Te substitution. The maximum PhiISC, found for the 3-phenyltellanyl derivative, was 59%. The results are interpreted in terms of the internal
合成了三种单取代的3-苯基硒基和3-苯基tellanyl BODIPY衍生物,并对它们的光谱性质进行了表征,并与含有类似物以及未取代的BODIPY衍生物的碘和氯原子的光谱性质进行了比较。发现荧光量子产率降低,而通过瞬态光谱法测定的系统间交叉量子产率(PhiISC)按H-> Cl-> Se / I-> Te取代的顺序增加。对于3-苯基碲烷基衍生物,发现最大的PhiISC为59%。根据取代基的内部重原子效应来解释结果。
Synthesis and evaluation of cyclic nitrone derivatives as potential anti-cancer agents
作者:Wei Zhou、Dongyan Ju、Yuhui Ao、Yu Liu、Jinbo Zhao
DOI:10.1007/s00044-021-02729-2
日期:2021.6
However, successful clinical cases of nitrone therapeutics are still lacking. Herein we report the synthesis and antiproliferative activity of a series of structurally diverse nitrone derivatives against a panel of 5 cancer cell lines, based on which indole- and pyrrole-fused were further evaluated by analogue preparation and in-vitro screening. Analogues with moderate to good potency were identified
A versatile, modular synthesis of monofunctionalized BODIPY dyes
作者:Volker Leen、Els Braeken、Kristof Luckermans、Carine Jackers、Mark Van der Auweraer、Noël Boens、Wim Dehaen
DOI:10.1039/b906164a
日期:——
A careful choice of the pyrrole building blocks allows the synthesis of a wide range of monohalogenated BODIPY dyes with excellent reactivity in palladium catalyzed coupling reactions.
We report herein an enantioselective intermolecular [2 + 2] photocyclization of alkenyl 2-pyrrolyl ketones using the bathochromic shift mediated by a chiral phosphoricacid. This synthetic method provides access to cyclobutanes with up to 98% ee. According to the UV–Vis spectra, the bathochromic effect was observed by mixing alkenyl 2-pyrrolyl ketones and a chiral phosphoricacid. A non-linear correlation
我们在此报道了烯基2-吡咯基酮的对映选择性分子间[2 + 2]光环化,利用手性磷酸介导的红移。这种合成方法可以得到 ee 高达 98% 的环丁烷。根据紫外-可见光谱,通过混合烯基2-吡咯基酮和手性磷酸观察到红色效应。在催化剂的 ee 和环加合物的 ee 之间观察到非线性相关性,表明两种底物在光环加成之前均与手性磷酸结合并形成二聚体复合物。
Aerobic oxidative α-iodination of carbonyl compounds using molecular iodine activated by a nitrate-based catalytic system
作者:Rok Prebil、Stojan Stavber
DOI:10.1016/j.tetlet.2014.08.055
日期:2014.10
The novel reaction system comprising air/NH4NO3(cat.)/I-2/H2SO4(cat.) is introduced as a simple, safe, cheap, efficient, and regioselective mediator for direct aerobic oxidative a-iodination of aryl, heteroaryl, alkyl, and cycloallcyl methyl ketones. The reaction system enabled the moderate to quantitative regioselective iodination of a large range of different methyl ketone derivatives including those bearing oxidizable heteroatom (S, N) substituents. Several activated aromatic compounds were also efficiently and selectively iodinated. The practical applicability of the presented reaction system was shown on 20 mmol scale under ambient pressure and 100% conversion of substrate was achieved. (C) 2014 Elsevier Ltd. All rights reserved.