我们在这里报告了通过涉及两个连续的钯催化的交叉偶联反应的序列,有效合成了多种取代的咪唑并[1,2- a ]吡啶,这是一种具有许多生物学特性的氮杂杂环家族。首先,我们证明了Hirao偶联在咪唑并吡啶衍生物的位置3、5和6处以高收率直接发生,从而获得了广泛的取代膦酸酯,次膦酸酯和氧化膦。在第二步中,发现磷酰咪唑并吡啶与芳基卤化物的直接CH-芳基化是有效且完全选择性的,这取决于空间位阻,导致中等至高收率的3-芳基取代的咪唑并吡啶。
This paper reports the design and the synthesis of a new family of compounds, the phostines, belonging to the [1,2]oxaphosphinane family. Twenty-six compounds have been screened for their antiproliferative activity against a large panel of NCI cancer cell lines. Because of its easy synthesis and low EC50 value (500 nM against the C6 rat glioma cell line); compound 3.1a was selected for further biological study. Moreover, the specific biological effect of 3.1a on the glioblastoma phylogenetic cluster from the NCI is dependent on its stereochemistry. Within that cluster, 3.1a has a higher antiproliferative activity than Temozolomide and is more potent than paclitaxel for the SF295 and SNB75 cell lines. In constrast with paclitaxel and vincristine, 3.1a is devoid of astrocyte toxicity. The original activity spectrum of 3.1a on the NCI cancer cell line panel allows the development of this family for use in association with existing drugs, opening new therapeutic perspectives.
Diversity-Oriented Synthesis toward Aryl- and Phosphoryl-Functionalized Imidazo[1,2-<i>a</i>]pyridines
We report herein an efficient synthesis of diversely polysubstituted imidazo[1,2-a]pyridines, a family of aza-heterocycles endowed with numerous biological properties, through a sequence involving two consecutive palladium-catalyzedcross-couplingreactions. First, we demonstrated that a Hirao coupling occurred straightforwardly in high yields at positions 3, 5, and 6 of imidazopyridine derivatives
我们在这里报告了通过涉及两个连续的钯催化的交叉偶联反应的序列,有效合成了多种取代的咪唑并[1,2- a ]吡啶,这是一种具有许多生物学特性的氮杂杂环家族。首先,我们证明了Hirao偶联在咪唑并吡啶衍生物的位置3、5和6处以高收率直接发生,从而获得了广泛的取代膦酸酯,次膦酸酯和氧化膦。在第二步中,发现磷酰咪唑并吡啶与芳基卤化物的直接CH-芳基化是有效且完全选择性的,这取决于空间位阻,导致中等至高收率的3-芳基取代的咪唑并吡啶。
reaction conditions for the preparation of pure aryl-H-phosphinate esters, originally developed by Sander and optimized by Petneházy, is reported. The influence of the reaction concentration has been investigated for the formation of phosphonite intermediates via direct addition of triethyl phosphite to the appropriate Grignardreagent. Subsequent hydrolysis of the phosphonites under acidic conditions gives