Synthesis and cytotoxicity of 2,4-disubstituted and 2,3,4-trisubstituted brominated pyrroles in murine and human cultured tumor cells

The 2,4-disubstituted and 2,3,4-trisubstituted brominated pyrroles were successfully prepared and demonstrated potent cytotoxicity against the growth of suspended murine and human tumors, i.e. leukemia and lymphomas, acute monocytic leukemia, and HeLa-S-3 uterine carcinoma. The brominated compounds were more selective in inhibiting the growth of tumors derived from human solid tumors. Nevertheless activity with some of the derivatives occurred in the human KB nasopharynx, SW-480 colon, and HCT ileum adenocarcinoma, and lung A549 carcinoma screens. In Tmolt(4) T cell leukemia cells DNA synthesis was reduced over 60 min from 25 to 100 mu M followed by RNA synthesis reduction. De novo purine synthesis was retarded with the regulatory enzyme PRPP-amino transferase being markedly inhibited with less effects dehydrogenase, dihydrofolate reductase,, nucleoside kinases. After 60 min incubations d[TTP] and d[GTP] pools were marginally reduced. In vitro ct-DNA studies that the agents may affect the DNA molecule itself with DNA viscosity and the Tmolt(4) studies suggest that DNA cross-linking of DNA strands may be present.