title: Dinuclear Cu(I) complexes of pyridyl-diazadiphosphetidines and aminobis(phosphonite) ligands: synthesis, structural studies and antiproliferative activity towards human cervical, colon carcinoma and breast cancer cells.
abstract: The copper(i) complexes containing phosphorus donor ligands such as diazadiphosphetidine, cis-{(o-OCH2C5H4N)P(μ-N(t)Bu)}2 (1) and aminobis(phosphonite), C6H5N{P(OC6H3(OMe-o)(C3H5-p))2}2 (2, PNP), have been synthesized. Treatment of 1 with copper iodide afforded the 1D coordination polymer [{Cu(μ-I)}2{(o-OCH2C5H4N)P(μ-N(t)Bu)}2]n (3). Treatment of 3 with 2,2'-bipyridine (bpy) and 1,10-phenanthroline (phen) produced mixed-ligand complexes [(L)2Cu2{(o-OCH2C5H4N)P(μ-N(t)Bu)}2][I]2 (4 L = bpy; 5 L = phen) in good yields. The reaction of 2 with copper iodide yielded a rare tetranuclear copper complex [(CuI)2C6H5N(PR2)2]2 (6), which on subsequent treatment with various pyridyl ligands produced binuclear complexes [{Cu(μ-I)(py)}2(μ-PNP)] (7), [Cu2(μ-I)(bpy)2(μ-PNP)]I (8), [Cu2(μ-I)I(bpy)(μ-PNP)] (9), [Cu2(phen)(bpy)(μ-PNP)](OTf)2 (10), [Cu2(μ-I)I(phen)(μ-PNP)] (11) and [Cu2(μ-I)(phen)2(μ-PNP)]I (12), in an almost quantitative yield. The new copper(i) complexes (4, 5 and 7-12) were tested for anti-cancer activity against three human tumor cell lines. Compounds 5, 10 and 12 showed in vitro antitumor activity 5-7 fold higher than cisplatin, the most used anticancer drug. These three most potent compounds (5, 10 and 12) were chosen for detailed study to understand their mechanism of action. The copper(i) compounds studied in the present investigation were found to inhibit tumor cell growth by arresting cells at the S-phase of the cell cycle. The characteristic nuclear morphology of treated cells showed signs of DNA damage. The experimental evidence clearly indicated that these compounds initiated apoptosis, which is mediated through the p53 pathway.
authors.affiliation: Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
authors.forename: Aijaz
authors.initials: A
authors.lastname: Rashid
authors.forename: Guddekoppa S
authors.initials: GS
authors.lastname: Ananthnag
authors.forename: Susmita
authors.initials: S
authors.lastname: Naik
authors.forename: Joel T
authors.initials: JT
authors.lastname: Mague
authors.forename: Dulal
authors.initials: D
authors.lastname: Panda
authors.forename: Maravanji S
authors.initials: MS
authors.lastname: Balakrishna
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects*; D002945:Cisplatin / Q000494:pharmacology; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D056831:Coordination Complexes / Q000737:chemistry* / Q000494:pharmacology*; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005260:Female; D006801:Humans; D008958:Models, Molecular; D015394:Molecular Structure; D014407:Tumor Cells, Cultured; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy* / Q000473:pathology
chemical_list: D000970:Antineoplastic Agents; D056831:Coordination Complexes; D003300:Copper; D002945:Cisplatin