Based on the previously described antimicrobial activity of salicylanilide derivatives, we designed and synthesized novel 2-(phenylcarbamoyl)phenyl 4-substituted benzoates. The most active salicylanilides were selected for esterification by various 4-substituted benzoic acids. These compounds were evaluated in vitro against Mycobacterium tuberculosis, including multidrug-resistant strains, nontuberculous mycobacteria (Mycobacterium avium and Mycobacterium kansasii), and eight bacterial and fungal strains. We also investigated the cytostatic and cytotoxic actions of the esters. The minimum inhibitory concentrations (MICs) against mycobacteria ranged from 0.125 to 8 μM. Interestingly, the drug-resistant strains exhibited the highest susceptibility without any cross-resistance with established drugs. 4-Bromo-2-[4-(trifluoromethyl)phenylcarbamoyl]phenyl 4-nitrobenzoate showed the most potent inhibition with MIC values ranging from 0.25 to 2 μM. Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus, were inhibited by two derivatives with MIC values of at least 0.49 μM, whereas Gram-negative bacteria and most of the tested fungi did not display any marked susceptibility. Benzoates exhibited no cytotoxicity at concentrations up to 50 μM but most caused significant cytostasis with IC₅₀ values lower than 10 μM. Some cytotoxicity-based selectivity indexes for drug-susceptible and drug-resistant M. tuberculosis as well as Staphylococci were higher than 100. These values indicate that some of these derivatives are promising candidates for future research.

基于先前描述的水杨酰苯胺衍生物的抗菌活性，我们设计和合成了新型的2-（苯基氨基甲酰基）苯基4-取代的苯甲酸酯。选择活性最高的水杨酰苯胺用于各种4-取代的苯甲酸的酯化。在体外评估了这些化合物对结核分枝杆菌的抵抗力，包括多重耐药菌株，非结核分枝杆菌（鸟分枝杆菌和堪萨斯分枝杆菌）。），以及八种细菌和真菌菌株。我们还研究了这些酯的细胞生长抑制作用和细胞毒性作用。对分枝杆菌的最小抑制浓度（MIC）为0.125至8μM。有趣的是，耐药菌株表现出最高的敏感性，与已建立的药物没有任何交叉耐药性。4-硝基苯甲酸4-溴-2- [4-（三氟甲基）苯基氨基甲酰基]苯基酯显示出最有效的抑制作用，MIC值为0.25至2μM。革兰氏阳性细菌，包括耐甲氧西林的金黄色葡萄球菌，被两种MIC值至少为0.49μM的衍生物抑制，而革兰氏阴性细菌和大多数被测真菌并未表现出任何明显的敏感性。苯甲酸盐在浓度高达50μM时无细胞毒性，但大多数引起明显的细胞停滞，IC ₅₀值低于10μM。对药物敏感性和耐药性结核分枝杆菌以及葡萄球菌的某些基于细胞毒性的选择性指数均高于100。这些值表明，其中一些衍生物有望用于未来的研究。