temperature results in a new four-component reaction giving previously undisclosed heterocyclic compounds, 4,6-diaryl-1,4,6,7-tetrahydro-2′H-spiro[pyrazolo[3,4-b]pyridine-5,5′-pyrimidine]s. Facile multipurpose three-component selective procedures to new spiroheterocycles are proposed. heterocycles - multicomponentreactions - selectivity - ultrasonication - microwave-assisted synthesis
研究了5-氨基吡唑类,巴比妥酸类和芳族醛类在常规加热,微波辐射或超声辐射下的多组分环缩合,发现温度是控制其化学选择性的主要因素。在高温下,取决于5-取代基中N取代基的性质,原料以两种不同的方式反应生成吡唑并[4',3':5,6]吡啶并[2,3- d ]嘧啶或它们的二氢类似物。氨基吡唑。处理在室温下导致新四组分反应得到先前未公开的杂环化合物,4,6-二芳基-1,4,6,7-四氢-2' ħ -螺[吡唑并[3,4- b]吡啶-5,5'-嘧啶] s。提出了针对新型螺杂环的简便的多用途三组分选择性程序。 杂环-多组分反应-选择性-超声处理-微波辅助合成
Pyrazolopyridines II: Synthesis and Antibacterial Screening of 6-Aryl-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic Acids
作者:Tahir Maqbool、Areesha Nazeer、Muhammad Naeem Khan、Mark C. Elliott、Misbahul Ain Khan、Muhammad Ashraf、Muhammad Nasrullah、Shafia Arshad、Munawar Ali Munawar
DOI:10.14233/ajchem.2014.15918
日期:——
5-Amino-3-methyl-1-phenyl-1H-pyrazole was prepared to react with various aromatic aldehydes and pyruvic acid to afford 6-aryl-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carbxylic acids. The prepared compounds were characterized by Mass, IR, 1H, 13C NMR spectra and CHN analysis data. Various 6-aryl-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carbxylic acids synthesized during this work were also evaluated for their antibacterial activities. Some of these compounds were found to be good antibacterial agents.
A simple and efficient procedure for the synthesis of pyrazoloisoquinoline and pyrazolopyridine derivatives by one-pot three-component condensation of aminopyrazoles, aldehydes, and cycloketones in water using carbonaceous material as solid acid catalyst is described. The procedure offers several advantages such as simple experimental and work-up procedures, high yield, recovery, and reusability of metal-free solid acid heterogeneous catalyst along with tolerance of a wide range of functional groups. (C) 2015 Elsevier Ltd. All rights reserved.
Pyrazolopyridines I: Synthesis of Some Pyrazolo[3,4-b]pyridine-4-carboxylates
作者:Tahir Maqbool、Misbahul Ain Khan、Muhammad Naeem Khan、Mark C. Elliott、Munawar Ali Munawar、Muhammad Nasrullah、Abdul Waheed Bhatti、Areesha Nazeer、Whei-Oh Lin
DOI:10.14233/ajchem.2013.14573a
日期:——
A series of ethyl 3-methyl-1-phenyl-6-aryl-1H-pyrazolo[3,4-b]pyridine-4-carboxylates were prepared by the reaction of 5-amino-3-methyl-1-phenyl-1H-pyrazole with various aromatic aldehydes and ethyl pyruvate. The structure elucidation of the prepared compounds was carried out by spectroscopic techniques (mass, IR, H-1 and C-13 NMR).