Rhodanine-3-acetic acid derivatives are attractive compounds with versatile effects. What is very important is that compounds of this type have many biological properties. They are tested, among others, as fluorescent probes for bioimaging and aldose reductase inhibitors. Rhodanine-3-acetic acid derivatives also have antibacterial, antifungal and anticancer activity. The presented work demonstrates that a slight change in the five-membered heterocyclic substituent significantly affects the properties of the compounds under consideration. Three rhodanine-3-acetic acid derivatives (A-1–A-3) were obtained in the Knoevenagel condensation reaction with good yields, ranging from 54% to 71%. High thermal stability of the tested compounds was also demonstrated above 240 °C. The absorption and emission maxima in polar and non-polar solvents were determined. Then, the possibility of using the considered derivatives for fluorescence bioimaging was checked. Compounds A-1 and A-2 were successfully used as fluorescent dyes of fixed cells of mammalian origin. In addition, biological activity tests against bacteria and fungi were carried out. Our results showed that A-1 and A-2 showed the most excellent antimicrobial activity among the newly synthesized compounds, especially against Gram-positive bacteria.

中文翻译：

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杂环取代基的微小变化是否会显着影响 (Z)-2-(5-亚苄基-4-氧代-2-硫代噻唑烷-3-基)乙酸衍生物的理化和生物性质？

绕丹宁-3-乙酸衍生物是具有多种功效的有吸引力的化合物。非常重要的是，此类化合物具有许多生物学特性。除其他外，它们还作为生物成像的荧光探针和醛糖还原酶抑制剂进行了测试。绕丹宁-3-乙酸衍生物还具有抗菌、抗真菌和抗癌活性。目前的工作表明，五元杂环取代基的微小变化会显着影响所考虑的化合物的性能。通过 Knoevenagel 缩合反应得到了三种绕丹宁-3-乙酸衍生物 (A-1–A-3)，收率良好，范围为 54% 至 71%。测试化合物在 240 °C 以上也表现出较高的热稳定性。测定了极性和非极性溶剂中的吸收和发射最大值。然后，检查了使用所考虑的衍生物进行荧光生物成像的可能性。化合物A-1和A-2已成功用作哺乳动物来源固定细胞的荧光染料。此外，还进行了针对细菌和真菌的生物活性测试。我们的结果表明，A-1和A-2在新合成的化合物中表现出最优异的抗菌活性，特别是针对革兰氏阳性菌。