Synthesis, in vitro Antiproliferative and Anti-HIV Activity of New Derivatives of 2-Piperazino-1,3-benzo[d]thiazoles

A series of N-{2-oxo-2-[4-(1,3-benzothiazol-2-yl)piperazin-1-yl]}-(het)arenecarboxamides 4a-1, sulfonamide derivatives 8a-i as well as benzothiazole-containing N-1-(2-oxoethyl)-N-1-arylthioureas 9a-c have been synthesized. Compounds 4a-l and 9a were evaluated, in vitro, for their antiproliferative activity against a large panel of human tumor-derived cell lines. Compounds 4l and 9a were the most potent analogs in this series, showing remarkable effects on human splenic B-lymphoblastoid cells (WIL-2NS) and human acute B-lymphoblastic leukemia (CCRF-SB) cell lines (4l: CC50 = 5.1 and 7.3 mu m, respectively), and compound 5 against CCRF-SB cell lines with CC50 = 2.3 mu M. These compounds are leading candidates for further development. Compounds 6-7a-i were screened as inhibitors against HIV-1 and HIV-2, and no activity has been witnessed.