Synthesis of New 1, 3, 4-Oxadiazole-Incorporated 1, 2, 3-Triazole Moieties as Potential Anticancer Agents Targeting Thymidylate Synthase and Their Docking Studies

• Main Authors: Mohammad Mahboob Alam, Abdulraheem SA Almalki, Thikryat Neamatallah, Nada M. Ali, Azizah M. Malebari, Syed Nazreen
• Format: Article
• Language: English
• Published: MDPI AG 2020-11-01
• Series: Pharmaceuticals
• Subjects: thymidylate synthase; cytotoxicity; 1,2,3-triazole; 1,3,4-oxadiazole; 5-fluoruracil; pemetrexed
• Online Access: https://www.mdpi.com/1424-8247/13/11/390

Thymidylate synthase (TS) has emerged as a hot spot in cancer treatment, as it is directly involved in DNA synthesis. In the present article, nine hybrids containing 1,2,3-triazole and 1,3,4-oxadiazole moieties (<b>6</b>–<b>14</b>) were synthesized and evaluated for anticancer and in vitro thymidylate synthase activities. According to in silico pharmacokinetic studies, the synthesized hybrids exhibited good drug likeness properties and bioavailability. The cytotoxicity results indicated that compounds <b>12</b> and <b>13</b> exhibited remarkable inhibition on the tested Michigan Cancer Foundation (MCF-7) and Human colorectal Carcinoma (HCT-116) cell lines. Compound <b>12</b> showed four-fold inhibition to a standard drug, 5-fluoruracil, and comparable inhibition to tamoxifen, whereas compound <b>13</b> exerted five-fold activity of tamoxifen and 24-fold activity of 5-fluorouracil for MCF-7 cells. Compounds <b>12</b> and <b>13</b> inhibited thymidylate synthase enzyme, with an half maximal inhibitory concentration, IC₅₀ of 2.52 µM and 4.38 µM, while a standard drug, pemetrexed, showed IC₅₀ = 6.75 µM. The molecular docking data of compounds <b>12</b> and <b>13</b> were found to be in support of biological activities data. In conclusion, hybrids (<b>12</b> and <b>13</b>) may inhibit thymidylate synthase enzyme, which could play a significant role as a chemotherapeutic agent.