This invention pertains generally to compounds of Formula I as described herein and compositions containing such compounds, as well as methods of using such compounds to treat bacterial infections. In certain aspects, the invention provides methods and compositions comprising these compounds for treating infections caused by Gram-negative bacteria.本發明大體上係關於如本文所描述之式I化合物及含有該等化合物之組合物,以及使用該等化合物治療細菌感染之方法。在某些態樣中,本發明提供用於治療由革蘭氏陰性細菌(Gram-negative bacteria)引起的感染之方法及包含此等化合物的組合物。