这项工作描述了在电化学条件下喹啉-4(1 H )-酮的有效 C3-H 卤化,其中卤化钾既充当卤化剂又充当电解质。该方案提供了在不分开的电池中方便地获得不同的卤代喹啉-4(1 H )-酮的方法,这些卤代喹啉-4(1 H)-酮具有独特的区域选择性、广泛的底物范围以及采用方便、环保的电解进行的克级合成。机理研究表明,卤素自由基可以促进喹诺酮类药物中N-H键的活化。
An Efficient Synthesis of (
<scp>1‐Methyl</scp>
)‐2‐phenyl‐4‐quinolones from (
<scp>
<i>N</i>
‐Methyl
</scp>
)isatoic Anhydride
作者:Jae In Lee
DOI:10.1002/bkcs.12239
日期:2021.4
substitution of (N‐methyl)isatoic anhydride with N,O‐dimethylhydroxylamine hydrochloride in CH3CN gave N‐methoxy‐N‐methyl 2‐(N‐methyl)aminobenzamide, which was treated with ethynyllithium reagents to afford 1‐[2‐(N‐methyl)amino]‐3‐phenyl‐2‐propyn‐1‐ones. The 6‐endo cyclization of 1‐[2‐(N‐methyl)amino]‐3‐phenyl‐2‐propyn‐1‐ones using NaOCH3 in CH3OH at 65 °C gave various (1‐methyl)‐2‐phenyl‐4‐quinolone
series of C-3 position perfluoroalkylated 4-quinolones were obtained smoothly via radical pathway in the presence of RfSO2Na and (NH4)2S2O8. The protocol features broad substrates scope, high regioselectivity, transition metal-free, and easily available fluorinating reagents, exhibiting potential application value for obtaining bioactive compounds.
在R f SO 2 Na 和(NH 4 ) 2 S 2 O 8存在下,通过自由基途径顺利获得了一系列C-3位全氟烷基化4-喹诺酮类化合物。该方案具有底物范围广、区域选择性高、不含过渡金属、易于获得的氟化试剂等特点,在获得生物活性化合物方面具有潜在的应用价值。
Synthesis of 4-Quinolones via a Carbonylative Sonogashira Cross-Coupling Using Molybdenum Hexacarbonyl as a CO Source
作者:Linda Åkerbladh、Patrik Nordeman、Matyas Wejdemar、Luke R. Odell、Mats Larhed
DOI:10.1021/jo502400h
日期:2015.2.6
A palladium-catalyzed CO gas-free carbonylative Sonogashira/cyclization sequence for the preparation of functionalized 4-quinolones from 2-iodoanilines and alkynes via two different protocols is described. The first method (A) yields the cyclized products after only 20 min of microwave (MW) heating at 120 degrees C. The second method (B) is a gas-free one-pot two-step sequence which runs at room temperature, allowing the use of sensitive substituents (e.g., nitro and bromide groups). For both protocols, molybdenum hexacarbonyl was used as a solid source of CO.
NorA is the most studied efflux pump of Staphylococcus aureus and is responsible for high level resistance towards fluoroquinolone drugs. Although along the years many NorA efflux pump inhibitors (EPIs) have been reported, poor information is available about structure-activity relationship (SAR) around their nuclei and reliability of data supported by robust assays proving NorA inhibition. In this regard, we focussed efforts on the 2-phenylquinoline as a promising chemotype to develop potent NorA EPIs. Herein, we report SAR studies about the introduction of different aryl moieties on the quinoline C-2 position. The new derivative 37a showed an improved EPI activity (16-fold) with respect to the starting hit 1. Moreover, compound 37a exhibited a high potential in time-kill curves when combined with ciprofloxacin against SA-1199B (norA+). Also, 37a exhibited poor non-specific effect on bacterial membrane polarisation and showed an improvement in terms of "selectivity index" in comparison to 1.