In recognition of the need for effective oral therapies to treat Gram-negative bacterial infections, efforts were directed toward identifying an oral prodrug of β-lactamase inhibitor clinical candidate QPX7728. Seventeen prodrugs were synthesized; key properties investigated were rates of cleavage to the active form in vitro, pharmacokinetics across species, and crystallinity. Compound 5-Na (QPX7831 Sodium) emerged with optimal properties across all key attributes.

中文翻译：

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硼酸 β-内酰胺酶抑制剂 QPX7728 的口服生物可利用前药 QPX7831 的选择

认识到需要有效的口服疗法来治疗革兰氏阴性细菌感染，努力寻找β-内酰胺酶抑制剂临床候选药物 QPX7728 的口服前药。合成了 17 种前药；研究的关键特性是体外裂解成活性形式的速率、跨物种的药代动力学和结晶度。化合物5-Na (QPX7831 Sodium) 在所有关键属性上均具有最佳性能。