Synthesis and Antitumor Activity of Guanylhydrazones from 6-(2,4-Dichloro-5-nitrophenyl)imidazo[2,1-<i>b</i>]thiazoles and 6-Pyridylimidazo[2,1-<i>b</i>]thiazoles
The design and synthesis of antitumor imidazothiazole guanylhydrazones are reported. The compounds were submitted to NCI for testing. All but one were more active than methyl-GAG. A few compounds were selected for further studies in search of a possible mechanism of action. The results from these studies and a final search with the NCI COMPARE algorithm suggest that the guanylhydrazones described in
Substituted 3-(5-Imidazo[2,1-<i>b</i>]thiazolylmethylene)-2-indolinones and Analogues: Synthesis, Cytotoxic Activity, and Study of the Mechanism of Action
作者:Aldo Andreani、Massimiliano Granaiola、Alessandra Locatelli、Rita Morigi、Mirella Rambaldi、Lucilla Varoli、Natalia Calonghi、Concettina Cappadone、Giovanna Farruggia、Claudio Stefanelli、Lanfranco Masotti、Tam L. Nguyen、Ernest Hamel、Robert H. Shoemaker
DOI:10.1021/jm2012694
日期:2012.3.8
The synthesis of substituted 3-(5-imidazo[2,1-b]thiazolylmethylene)-2-indolinones and analogues is reported. Their cytotoxic activity was evaluated according to protocols available at the National Cancer Institute (NCI), Bethesda, MD. The action of selected compounds was examined for potential inhibition of tubulin assembly in comparison with the potent colchicine site agent combretastatin A-4. The most potent compounds also strongly and selectively inhibited the phosphorylation of the oncoprotein kinase Akt in cancer cells. The effect of the most interesting compounds was examined on the growth of HT-29 colon cancer cells. These compounds caused the cells to arrest in the G2/M phase of the cell cycle, as would be expected for inhibitors of tubulin assembly.
Ligand Based Approach to L-Type Calcium Channel by Imidazo[2,1-<i>b</i>]thiazole-1,4-Dihydropyridines: from Heart Activity to Brain Affinity
The synthesis, characterization, and functional in vitro assay in cardiac and smooth muscle (vascular and nonvascular) of a series of 4-imidazo[2,1-b]thiazole-1,4-dihydropyridines are reported. To define the calcium blocker nature of the imidazo[2,1-b]thiazole-1,4-DHPs and their selectivity on Ca(v)1.2 and Ca(v)1.3 isoforms, we performed binding studies on guinea pig atrial and ventricular membranes on intact cells expressing the cloned Ca(v)1.2a subunit and on rat brain cortex. To get major insights into the reasons for the affinity for Ca(v)1.2 and/or Ca(v)1.3, molecular modeling studies were also undertaken. Some physicochemical and pharmacokinetic properties of selected compounds were calculated and compared. All the biological data collected and reported herein allowed us to rationalize the structure-activity relationship of the 4-imidazo[2,1-b]thiazole-1,4-DHPs and to identify which of these enhanced the activity at the central level.