Palladium‐Catalyzed Regioselective Dehydrogenative C–H/C–H Cross‐Coupling of Pyrroles and Pyridine
<i>N</i>
‐Oxides
作者:Shanshan Liu、C. Christoph Tzschucke
DOI:10.1002/ejoc.201600680
日期:2016.7
The palladium-catalyzed cross-dehydrogenative coupling of N-alkylpyrroles and pyridine N-oxides gave the corresponding pyrrolylpyridine N-oxides. Cu(OAc)2·H2O as a co-catalyst with air as the terminal oxidant led to preferential coupling in the β-position, whereas AgOAc as the stoichiometric oxidant resulted in preferential coupling in the α-position. N-(Benzyloxymethyl)pyrrole derivatives were deprotected
Aspirin Derivative 5-(Bis(3-methylbut-2-enyl)amino)-2-hydroxybenzoic Acid Improves Thermotolerance via Stress Response Proteins in Caenorhabditis elegans
作者:Xiao-Bing Huang、Gui-Sheng Wu、Lei-Yu Ke、Xiao-Gang Zhou、Yue-Hu Wang、Huai-Rong Luo
DOI:10.3390/molecules23061359
日期:——
Aging is a major risk factor for many prevalent diseases. Pharmacological intervention to improve the health span and extend the lifespan could be a preventive elixir for aging and age-related diseases. The non-steroid anti-inflammation medicine aspirin was reported to delay aging in Caenorhabditis elegans (C. elegans) and mice. We are wondering if the analogues of aspirin could also present antiaging activity. Here, we synthesized several aspirin derivatives and investigated their thermotolerance and antiaging effect in C. elegans. One of the compounds, 5-(bis(3-methylbut-2-en-1-yl)amino)-2-hydroxybenzoic acid, moderately increased the survival of C. elegans under heat stress, but could not extend the lifespan under optimum conditions. This compound could increase the mRNA level of stress response gene gst-4, and the mRNA and protein expression level of heat shock protein hsp-16.2 under heat stress. The failure of activating the transcription factor DAF-16 might explain why this compound could not act as aspirin to extend the lifespan of C. elegans. Our results would help further the investigation of the pharmacological activity of aspirin analogues and the relationship between structures and activity.
衰老是许多常见疾病的主要危险因素。通过药物干预提高健康寿命和延长生命可能是延缓衰老和对抗年龄相关疾病的预防良药。非甾体抗炎药阿司匹林已被报道能延缓秀丽隐杆线虫(Caenorhabditis elegans, C. elegans)和小鼠的衰老。我们想知道阿司匹林的类似物是否也能表现出抗衰老活性。本研究中,我们合成了几种阿司匹林衍生物,并检测了它们在C. elegans中的耐热性和抗衰老作用。其中一种化合物,5-(双(3-甲基丁-2-烯-1-基)氨基)-2-羟基苯甲酸,在热胁迫下适度提高C. elegans的存活率,但不能在最佳条件下延长其寿命。该化合物能在热胁迫下增加应激反应基因gst-4的mRNA水平,以及热休克蛋白hsp-16.2的mRNA和蛋白表达水平。未能激活转录因子DAF-16可能是该化合物不能像阿司匹林那样延长C. elegans寿命的原因。我们的结果将进一步推动对阿司匹林类似物药理活性的研究,以及它们结构与活性之间的关系。
Synthesis of N-alkyl pyrroles via decarboxylation/dehydration in neutral ionic liquid under catalyst-free conditions
作者:Veena D. Yadav、Shashikant U. Dighe、Sanjay Batra
DOI:10.1039/c4ra09797a
日期:——
A catalyst-free benign route toN-alkyl pyrroles by reacting aromatic, heteroaromatic or aliphatic aldehydes with 4-hydroxyproline in neutral ionic liquid under microwave irradiation is presented.
A new facile approach to N-alkylpyrroles from direct redox reaction of 4-hydroxy-l-proline with aldehydes
作者:ZhiQin Zou、ZeJun Deng、XinHong Yu、ManMan Zhang、SiHan Zhao、Ting Luo、Xin Yin、Hui Xu、Wei Wang
DOI:10.1007/s11426-011-4445-1
日期:2012.1
An unprecedented acetic acid-catalyzed efficient access to N-alkylpyrroles from reaction of 4-hydroxy-l-proline with a variety of aldehydes has been achieved in good to excellent yields under mild reaction conditions.
An enantioselective synthesis of α-alkylated pyrroles <i>via</i> cooperative isothiourea/palladium catalysis
作者:W. Rush Scaggs、Toya D. Scaggs、Thomas N. Snaddon
DOI:10.1039/c8ob02600a
日期:——
Herein we describe the direct enantioselective Lewis base/Pd catalysed α-allylation of pyrrole acetic acid esters. This provides high isolated yields of highly enantioenriched products and exhibits broad reaction scope with respect to both reaction partners. The products can be readily elaborated in a manner which points towards potential applications in target directed synthesis.