title: Cytotoxicity of new 5-phenyl-4,5-dihydro-1,3,4-thiadiazole analogues.
abstract: A series of 5-phenyl-4,5-dihydro-1,3,4-thiadiazoles were synthesized and their cytotoxicity was examined against four human cancer cell lines, e.g. lung cancer (A549), ovarian cancer (SK-OV-3), skin cancer (SK-MEL-2), and colon cancer (HCT15). The title compounds were synthesized by condensation of thiosemicarbazide with substituted benzaldehydes, followed by cyclization with acetic anhydrides in good yields. Most of the compounds exhibited significant suppressive activity against the growth of all of the cancer cell lines. The 4-hydroxy analogue of 5-phenyl-4,5-dihydro-1,3,4-thiadiazole (2h) was most active in the inhibition of growth of the SK-MEL-2 cell line, with an IC(50) value of 4.27 µg/ml; followed by compound 2a (IC(50) 5.16 µg/ml). The compounds 2j, 2h, and 2b, bearing 3-methoxy-4-hydroxy-, 4-hydroxy- and 4-methyl substituents in the C-5 phenyl ring respectively, exhibited the highest activity against the SK-OV-3 (IC(50) 7.35 µg/ml), HCT15 (IC(50) 8.25 µg/ml) and A549 (IC(50) 9.40 µg/ml) cell lines, respectively. A structure-activity relationship study revealed that an optimal electron density on the C-5 phenyl ring of 1,3,4-thiadiazoles is crucial for their cytotoxic activity against the human cancer cell lines used in the present study.
authors: Division of Bioscience, Dongguk University, Gyeongju 780–714, Republic of Korea.
authors: Mohammad Sayed
authors: MS
authors: Alam
authors: Lijun
authors: L
authors: Liu
authors: Dong Ung
authors: DU
authors: Lee
mesh_terms: D000089:Acetic Anhydrides / Q000737:chemistry; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000633:toxicity*; D001547:Benzaldehydes / Q000737:chemistry; D045744:Cell Line, Tumor; D002477:Cells / Q000187:drug effects*; D003500:Cyclization; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D012663:Semicarbazides / Q000737:chemistry; D013329:Structure-Activity Relationship; D013830:Thiadiazoles / Q000138:chemical synthesis / Q000737:chemistry* / Q000633:toxicity
chemical_list: D000089:Acetic Anhydrides; D000970:Antineoplastic Agents; D001547:Benzaldehydes; D012663:Semicarbazides; D013830:Thiadiazoles; C058949:1,3,4-thiadiazole; C005151:thiosemicarbazide