time-efficient preparation of a variety of functionalized aromatic heterocyclic products exhibiting an isoquinoline core. The approach is based on the normal electron-demand [4 + 2] aza-Diels–Alder cycloaddition of electron-rich N-aryl imines with arynes. Using this strategy, an expeditious total synthesis of the naturally occurring benzo[c]phenanthridinealkaloid nornitidine was achieved.
已经开发了两个级联反应,以高效地制备具有异喹啉核心的各种功能化芳族杂环产物。该方法基于富电子的N-芳基亚胺与芳烃的正常电子需求[4 + 2] aza-Diels-Alder环加成反应。使用该策略,可以快速合成天然存在的苯并[ c ]菲啶生物碱去甲替尼丁。
Synthesis of novel pyrazolo[3,4-b]pyridine derivatives in aqueous medium
作者:Mehdi Mohammad Baradarani、Hadi Zare Fazlelahi、Ahmad Rashidi、John Arthur Joule
DOI:10.24820/ark.5550190.p010.389
日期:——
A synthesis of 5-(3,3-dimethyl-3H-indol-2-yl)-3-methyl-1H-pyrazolo[3,4-b]pyridines by the reaction of variously substituted aminomethylene malondialdehydes [2-(3,3-dimethyl-3H-indol-2-ylidene)malondialdehydes] with 5amino-1-aryl-3-methylpyrazoles in the presence of p-toluenesulfonic acid in water is described.
The stereoselective syntheses of a library of novel spiro-tethered pyrazolo[3,4-b]quinoline–pyrrolidine/pyrrolothiazole/indolizine–oxindole/acenaphthene hybrid heterocycles have been achieved through the 1,3-dipolar cycloaddition of azomethine ylides generated in situ from α-amino acids and 1,2-diketones to dipolarophiles derived from pyrazolo[3,4-b]quinoline derivatives.
通过从现场原位生成的偶氮甲ine啶基的1,3-偶极环加成反应,可以实现新型螺拴的吡唑并[3,4- b ]喹啉-吡咯烷/吡咯并噻唑/吲哚嗪-ox吲哚/ ac杂杂杂环的文库的立体选择性合成。吡唑并[3,4- b ]喹啉衍生物衍生的α-氨基酸和1,2-二酮。
We herein describe a C4 sulfonylmethylation of pyrazol-5-amines with glyoxylic acid and sodium sulfinates. The reaction only needed water as a solvent, and it featured mild reaction conditions, simple operation, and high regioselectivity. Various C4 sulfonylmethylated pyrazol-5-amines were obtained in good to excellent yields. Moreover, this sulfonylmethylation method was applicable for C(sp2)–H sulfonylmethylation