α,β-Epoxy Esters in Multiple C–O/C–N Bond-Breaking/Formation with 2-Aminopyridines; Synthesis of Biologically Relevant (Z)-2-Methyleneimidazo[1,2-a]pyridin-3-ones
作者:Sankar Guchhait、Garima Priyadarshani、Neha Hura
DOI:10.1055/s-0033-1339105
日期:——
A newreaction of aryl 2,3-epoxy esters with 2-aminopyridines has been developed that involvesmultiple C–O/C–N bond-breaking/formation reactions in one chemical step. Compared with known reactions of α,β-epoxy esters, which take place through oxiranyl C–O or C–C bond cleavage, the present reaction exploits the tendency of the oxirane ring to act as a bi-electrophile. Thus, the reaction follows a unique
Scaffold-Hopping of Aurones: 2-Arylideneimidazo[1,2-<i>a</i>]pyridinones as Topoisomerase IIα-Inhibiting Anticancer Agents
作者:Garima Priyadarshani、Anmada Nayak、Suyog M. Amrutkar、Sarita Das、Sankar K. Guchhait、Chanakya N. Kundu、Uttam C. Banerjee
DOI:10.1021/acsmedchemlett.6b00242
日期:2016.12.8
the first time. 2-Arylideneimidazo[1,2-a]pyridinones as potential topoisomerase IIα (hTopoIIα)-targeting anticancercompounds were considered. A multifunctional activator, polyphosphoric acid, enabled to realize a cascade reaction of 2-aminopyridine with 2,3-epoxyesters toward synthesis of 2-arylideneimidazo[1,2-a]pyridinones. Most of the compounds exhibited hTopoIIα-selective poison activity with efficiency
首次研究了生物活性天然产物金黄色素的脚手架跳跃。有人考虑将2-Arylideneimidazo [1,2- a ]吡啶酮作为潜在的拓扑异构酶IIα(hTopoIIα)靶向抗癌化合物。多功能活化剂多磷酸能够实现2-氨基吡啶与2,3-环氧酯的级联反应,从而合成2-芳基亚氨基咪唑[1,2- a]]吡啶酮。大多数化合物表现出hTopoIIα选择性毒性活性,其效率高于依托泊苷和DNA结合特性,但不与hTopo I相互作用。这些化合物在纳摩尔浓度范围内表现出明显的抗增殖活性,对正常细胞的毒性相对较弱,抑制了侵袭性,并且凋亡作用。还观察到抑制微管蛋白装配的活性CDK1和pCDK1。有趣的是,与具有相同取代作用的相应母体金黄色素相比,具有代表性的强效化合物的hTopoIIα抑制作用(体外和离体研究)和抗增殖活性更高,表明这种支架跳跃策略在药物化学研究中的重要性。
Efficient Synthesis ofα,β-Epoxy Carbonyl Compounds in Acetonitrile:Darzens Condensation of Aromatic Aldehydes with Ethyl Chloroacetate
作者:Zong-Ting Wang、Li-Wen Xu、Chun-Gu Xia、Han-Qing Wang
DOI:10.1002/hlca.200490177
日期:2004.8
The Darzens reaction of ethyl 2-chloroacetate (1) with aromatic aldehydes 2 in the presence of polymer-supported or nonsupported quaternary ammonium salts proceeds under mildconditions by phase-transfercatalysis to give the corresponding epoxides 3 in satisfactory yields (Tables 1 and 2). With both MeCN as solvent and polystyrene-supported catalysts, diastereoselective Darzens reactions proceed in