Synthesis and Preliminary Cancer Activity of Chelidonic Acid Polyesters Containing the Triphenylarsenic,Triphenylantimony, and Triphenylbismuth Moiety

Polyesters derived from the interfacial reaction of the salt of chelidonic acid and triphenylarsenic dibromide, triphenylantimony dichloride, and triphenylbismuth dichloride are formed in moderate yield using commercially available reactants. IR data shows new bands characteristic of the formation of the M-O bond. MALDI MS shows formation of ion fragment clusters to two units. The polymers were tested for their ability to inhibit prostate, colon, breast (two cell lines), and pancreatic (two cell lines) cancer cells. All polymers showed ability to inhibit some of the cancer cell lines. The arsenic polymer exhibits good inhibition of the AsPC-1 pancreatic cell line. All three polymers inhibit the estrogen independent 7233 cell line to a much greater extent compared to inhibition of the 7259 estrogen positive receptor cell line. The arsenic and bismuth polymers also exhibit decent inhibition of the other cancer cell lines while the antimony polymer shows only decent inhibition of the 3465 prostate cell line.     

Synthesis,Structural Characterization,and Ability to Inhibit Cancer Growth of a Series of Organotin Poly(ethylene glycols)

A series of organotin poly(ethylene glycols) were synthesized including the first water soluble organotin polymers. These products are all polymeric with weight average molecular weights about 10⁵. Infrared spectroscopy shows the presence of moieties from both reactants and the formation of the Sn–O linkage. F MALDI MS shows the presence of up to over a hundred units and by isotopic abundance the presence of one, two, and three tin-containing ion fragments. The polymers inhibit the growth of cancer cell lines from bone, prostate, colon, breast, and lung cancers. In a number of instances chemotherapeutic index values of two and greater are found consistent with these polymers being more active against cancer cells than non-cancerous healthy cells. Thus, some of these polymers show good promise as a new family of anticancer drugs including the water-soluble organotin-containing polymers.     

Synthesis and Characterization,Including Cancer Cell Line Inhibition,of Group VA (Group 15)-Containing Polyesters from Reaction with Camphoric Acid

Polyesters were rapidly synthesized employing interfacial polymerization from reaction of the salt of camphoric acid with Group VA (Group 15) triphenylmetallic dihalides. Yields range from 25 to 46 percent with chain lengths about 250. Infrared spectroscopy shows the formation of two new bands one assigned to the symmetrical M–O stretching and the second assigned to the asymmetrical M–O stretching. The bridging structure about the metal atom increases as the metal atom size increases. MALDI MS and proton NMR are consistent with the formation of the polyester structure. Ion fragment clusters to four to six units are identified. The polymers show good inhibition of a group of cancer cell lines including two pancreatic human cancer cell lines. In comparison with other metal/camphoric acid polymers, the metallocene polymers exhibit low EC₅₀ to the nanogram/ml range, and CI₅₀ values greater than one thousand for the hafnocene and zirconocene products. If this trend continues, the emphasis should be on the Group IVB metallocenes with respect to efforts to create anticancer drugs.     

Synthesis of Organotin Polyamine Ethers Containing Acyclovir and their Preliminary Anticancer and Antiviral Activity

Organotin polyamine ethers containing acyclovir in their backbone were synthesized in moderate to high yield employing the aqueous interfacial polycondensation system. The products are high molecular weight polymers. Infrared spectroscopy of the products shows new bands characteristic of the formation of Sn–N and Sn–O bonds consistent with the proposed structure. MALDI-TOF MS below 2000 Da shows the presence of organotin and acyclovir units containing these two moieties. The products show moderate inhibition of a number of cancer cell lines and exhibit the ability to inhibit a number of viruses, particularly the herpes simplex virus-1 and varicella zoster virus that are responsible for herpes, chicken pox and shingles.     

Synthesis,Structural Characterization,and Initial Evaluation as Anticancer Drugs of Dibutyltin Polyamines Derived from Various 4,6-Diaminopyrimidines

A number of diaminopyrimidines have been incorporated into dibutyltin polyamines with molecular weights ranging from 3.5 × 10⁴ to 3.7 × 10⁶ and product yields from 47 to 88%. Infrared spectroscopy is consistent with the inclusion of the diaminopyridines into the polymer backbone with the IR spectroscopy showing the formation of the Sn–N bond as well as the presence of bands from both reactants being present in the polymer. F MALDI MS is also consistent with the products being polymeric and containing units from both the dibutyltin and pyrimidine reactants. The products exhibit good inhibition of cancer cell lines including those derived from human lung, bone, breast, prostrate, and colon cancers. Inhibition occurs within the same concentration range, and lower than that of the most widely employed chemotherapeutic drug, cisplatin.     

Synthesis and Initial Cell Line Results of Organotin Polyethers Containing Diethylstilbestrol

Organotin polyethers containing the synthetic estrogen diethylstilbestrol have been made in moderate yield with chain lengths ranging from 20 to 200 repeat units employing the interfacial polycondensation procedure. Infrared spectroscopy shows the absence of the O–H group and formation of the Sn–O linkage consistent with the formation of the polyether. F-MALDI MS results are consistent with the presence of organotin-containing fragmentation clusters containing one and two tin atoms and ion fragments up to about 30 units long. The polymers all show moderate to good inhibition of a group of cancer cell lines including colon, breast and prostrate cell lines. Many of them show significant CI₅₀ values showing a preference to inhibit the cancer cell lines in preference to the normal cell lines. This article is dedicated to Professor Astruc.     

Synthesis and Preliminary Cancer Cell Line Results for the Product of Organotin Dihalides and Alpha-Cyano-4-Hydroxycinnamic Acid

High polymer poly(ester ethers) are rapidly synthesized in good yield employing the interfacial polycondensation reaction system. Infrared spectroscopy shows the formation of new bands derived from the Sn–O and Sn–O(CO) linkages. It also shows that the products exist as alternating Sn–O and Sn–O(CO) linkages. MALDI MS shows formation of ion fragment clusters several units in length. The products show reasonable inhibition of a variety of cancer cell lines including two pancreatic cancer cell lines.     

Synthesis and Structural and Initial Cancer Cell Line Characterization of Organotin Polyesters from Dipicolinic Acid

The interfacial polymerization is employed to produce high polymer poly(ester ethers) from the reaction of the salt of dipicolinic acid and various organotin dihalides. They are rapidly synthesized with yield increasing as the length of the organotin alkyl chain increases. Infrared spectroscopy shows the formation of new bands derived from the Sn–O and Sn–O(CO) linkages. IR also shows that the products exist as a combination of molecular geometries about the tin atom. MALDI MS shows formation of ion fragment clusters to five and six units in length. The products show good inhibition of a variety of cancer cell lines including two pancreatic cancer cell lines.     

Synthesis and Characterization of Organotin Polyesters Derived from 3,5-Pyridinedicarboxylic Acid

Organotin polyesters were synthesized from the interfacial condensation of organotin dihalides and salts of 3,5-pyridinedicarboxylic acid. The polymers are synthesized in moderate to high yields and are moderate to high polymers. MALDI MS, IR spectral, and NMR spectral results are consistent with the proposed structure. The Sn–O stretching band is found at about 1,028 cm^?1. Infrared spectra are consistent with majority of the products having a non-bridged structure about the tin. All of the polymers exhibit some inhibition of two pancreatic cancer cell lines. The dibutyltin and dicyclohexyltin products show sufficiently good inhibition of both cell lines as to merit further testing.     

A kinetic study of the thermal degradation of chitosan‐metal complexes

The thermal degradation of metal complexes formed by chitosan with Cu(II), Ni(II), Co(II), and Hg(II), at different metal concentrations, was studied by thermogravimetric analysis in a nitrogen atmosphere over the temperature range 25–800°C. The results indicate that thermal degradation of chitosan and chitosan‐metal ion complexes could be of one or two‐stage reaction. In the thermal degradation of chitosan with metal complexes, the temperature of initial weight loss and the temperature of maximum weight loss rate decrease. Fourier transform infrared spectroscopy was used to probe the interaction of chitosan with metal ions. The bands of ? N? H, ? C?O, ? C? O? C? groups of chitosan are shifted or change their intensity in the presence of metal. These changes in the characteristic bands are taken as evidence of the influence of metal ions on the thermal stability of chitosan. Broido's method was employed to evaluate the activation energies as a function of the degree of degradation. The presence of metal ions provoked a decrease in the thermal stability of chitosan, which became more marked when the concentration of metal was increased. The dynamic study showed that the apparent activation energy values of the main stage of the thermal degradation of chitosan‐metal complexes decrease as the strength of the polymer‐metal interaction increases. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis of Organotin Polyesters from Reaction of the Salt of <Emphasis Type="SmallCaps">d</Emphasis>-Camphoric Acid and Organotin Dihalides and Initial Anticancer Activity

Organotin polyesters were synthesized from d-camphoric acid. Since d-camphoric acid is a natural product, this is part of the green chemistry initiative. Further, synthesis occurred employing commercially available reactants and the interfacial system which is used industrially to synthesize aramids and polycarbonates. Thus, scale-up is straightforward. Polymers were synthesized employing the interfacial reaction between various organotin dihalides and the salt of d-camphoric acid. Reaction was rapid occurring in 30 s and less. Product yield was good except for the product from dioctyltin dichloride. The products are polymeric with chain lengths from 230 to 2200. Structural characterization with infrared spectrometry and MALDI MS are consistent with the formation of organotin polyesters containing the camphoric acid moiety within its backbone. IR shows formation of the Sn–OOC(O) linkage with the polymer having a combination of bridging and non-bridging geometrical arrangements about the tin atom. MALDI MS shows ion fragment to two and three repeat units. The products exhibit good ability to inhibit a battery of cancer cells including those from pancreatic cancer. The effective concentration for inhibition of the cancer cell lines are generally in the same range as those found for cisplatin and in the ng/mL range.     

Analysis Characterization and Some Properties of Polyacrylamide Copper Complexes

The complexation of polyacrylamide (PAam) with Cu⁺² metal ions was investigated. The metal complexes were characterized by FTIR, UV-Vis and DSC analysis. The Fourier transform infrared spectroscopy was used to study the characteristic shifts in the maximum absorbance bands of N-H amide C=O and N-H₂ absorption bands. UV-Vis spectroscopy was also used to follow the complex formation of PAam-Cu⁺². UV-Vis spectroscopy shows the appearance of a new band that was absent both in the polymer and its salt solutions.

Thermal analysis of PAam-Cu⁺² complexes was studied using DSC. The shifts in Tg values could be attributed to the improvement in the rigidity of PAam in the presence of Cu⁺² associated with the polymer chain. Pure polyacrylamide polymer is electrically insular. The electrical conductivity improved by several orders of magnitude after the complexation process.

AFM was used to image the surface features of PAam and PAam-Cu⁺²complex films. The association of polyacrylamide with Cu⁺² metal ions at 2.5% (w/w) concentration, showed the formation of large grains with roughness 0.5 µm. Increasing the concentration of PAam-Cu⁺² complex up to 25% (w/w), showed different and surprising results: instead of film with large grains, rods 1 µm in diameter were formed.     

New chelating polymers for heavy metal ion sorption

Twenty‐six new chelating polymers containing pyridyl (Py) or bipyridyl (Bipy) units as ligating centers were synthesized by free‐radical reactions of 2‐vinylpyridine, 4‐vinylpyridine, or 4‐methyl‐4′‐vinyl‐2,2′‐bipyridine with different dimethacrylate crosslinkers and evaluated for heavy metal ion sorption from aqueous solutions. Both the Py‐ and Bipy‐containing polymers are highly selective for Cu(II) over Co(II) and Ni(II) and for Hg(II) over Cd(II). The polymeric materials with Bipy binding sites generally exhibit more efficient metal ion sorption than do the corresponding Py‐containing copolymers. The metal ion sorption capacity of the copolymer also depends on the structure of the dimethacrylate crosslinker. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 849–856, 1999     

Organotin Polyesters from 1,1′-Ferrocenedicarboxylic Acid

Organotin polyesters have been synthesized employing the classical interfacial polycondensation of organotin dihalides and the salt of 1,1′-ferrocenedicarboxylic acid. The products are oligomeric (DP = 5) to polymeric (DP = 220). The presence of new IR bands characteristic of formation of the Sn–O band are present. Ion fragments characteristic of the repeat unit and greater are found employing F MALDI MS.     

Synthesis and performances of 9,9-bis(perfluorohexylethyl propionate) fluorene copolymers

2,7-dibromo-9,9-bis(perfluorohexylethyl propionate) fluorene was synthesized by Michael addition reaction using 2,7-dibromofluorene and perfluorohexyl ethyl acrylate as the reactants. 9,9-Bis(perfluorohexylethyl propionate) fluorene copolymers were then synthesized by Suzuki coupling reaction with 2,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborane-diyl)-9,9 -dioctyl fluorene, 2,7-dibromo-9,9-dioctyl fluorene and 2,7-dibromo-9,9-bis(perfluorohexylethyl propionate) fluorene as the monomers. The fluorinated fluorene copolymers were characterized and investigated via Fourier infrared spectroscopy (FTIR), hydrogen nuclear magnetic resonance spectroscopy (¹HNMR), ultraviolet absorption spectroscopy (UV–vis), cyclic voltammetry (CV) and photoluminance spectroscopy (PL). Because of the long fluorine-containing alkyl side chain, the ultraviolet absorption peak of 9,9-bis(perfluorohexylethyl propionate) fluorene is blue-shifted compared with poly(9,9-dioctylfluorene)(PF8). The LUMO energy level increases and the energy band gap of copolymers widens. Due to the self-assembly of the long fluoroalkyl side chain, the photoluminance spectra of 9,9-bis(perfluorohexylethyl propionate) fluorene copolymers exhibit a new excimer emission peak at 550 nm. The photoluminance stabilities of the copolymers under irradiation and humid conditions are significantly improved due to protective effect from the long fluoroalkyl side chain. After being irradiated under 500 W iodine tungsten lamp or kept under 70% relative humid conditions, the 9,9-bis(perfluorohexylethyl propionate) fluorene copolymers showed much better photoluminance stability than that of poly(9,9-dioctylfluorene) (PF8). These show that introducing long fluoroalkyl side chain into conjugated polymer main chain is a promising strategy to improve environmental stability of devices based on organic conjugated polymers.     

Impact of Functionalized Polystyrenes as the Electron Injection Layer on Gold and Aluminum Surfaces: A Combined Theoretical and Experimental Study

At metal/organic interfaces, the insertion of an organic monolayer can significantly modify the surface properties of the substrate, especially in terms of charge injection across the interface. Herein, we study the formation of an insulating monolayer of morpholine or amine-functionalized polystyrene on Al(111) and Au(111) surfaces and its impact on surface work-function and charge injection. First-principles calculations based on Density Functional Theory have been carried out and point to a significant decrease in the work-function of modified metal surfaces; this is in very good agreement with ultraviolet photoemission spectroscopy measurements performed on the Au(111) surface. In addition, a bilayer cathode, consisting of a thin film of high-work-function metal, such as Al and Au, and a layer of amine-functionalized polystyrene, was also fabricated and tested in organic light-emitting diodes. Such bilayer structures exhibit substantially enhanced efficiency when compared with controls without the functionalized polymers. Our combined theoretical and experimental investigation gives insight into how a thin layer of a commodity polymer can be used to transform rather high-work-function metals into high-performance cathodes to provide efficient electron injection.     

Preliminary Results for the Inhibition of Pancreatic Cancer Cells by Organotin Polymers

Pancreatic cancer kills nearly all patients within 3–6 months after detection. There is no effective chemotherapy for it. We have found a number of organotin polymers that are effective at inhibiting pancreatic cancer cell lines with Chemotherapeutic Index values greater than two with some to values of 50.     

Thermally stable polyureas and poly(urea‐imide)s containing zinc and nickel napthtrien complexes

Two new napthtrien metal complexes, MNapth₂trien; where M = Zn and Ni, were synthesized and used for the synthesis of metal‐containing polyureas and poly(urea‐imide)s. MNapth₂trien underwent polymerization reaction with two diisocyanates, namely, 4,4′‐diphenylmethane diisocyanate and isophorone diisocyanate to yield polyureas. Poly(urea‐imide)s were obtained by the synthesis of metal‐containing isocyanate‐terminated polyurea prepolymers from the reaction between MNapth₂trien and excess diisocyanates, which could then undergo further reaction with different dianhydrides. The dianhydrides used were pyromellitic dianhydride and benzophenone‐3,3′,4,4′‐tetracarboxylic dianhydride. The polymers were characterized by infrared, nuclear magnetic resonance, elemental analysis, X‐ray diffraction, solubility, and viscosity. Glass transition temperature of the polymers was obtained from differential scanning calorimetry and dynamic mechanical thermal analysis. Thermal stability of polymers was studied by thermogravimetric analysis in air. It was found that the resulting metal‐containing polymers exhibited good thermal stability. Initial decomposition temperatures of the polymers depend on the amount of MNapth₂trien in the polymer composition. Char yields of metal‐containing poly(urea‐imide)s are higher than those of metal‐containing polyureas. Most metal‐containing polymers show good solubility in organic solvents. Shore D hardness test indicates that metal‐containing poly(urea‐imide)s are hard materials. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Electrochromic Solid-State Devices Using Organic-Metallic Hybrid Polymers

Organic-metallic hybrid polymers are formed by the complexation of metal ions with organic modules bearing two coordination sites. The hybrid polymers consisting of bis-terpyridines and metal ions such as Fe(II) or Ru(II) have a specific color based on the metal-to-ligand charge transfer (MLCT) absorption. Cyclic voltammograms of the polymers exhibit a reversible redox wave according to the redox reaction of the metal ions. Interestingly, a polymer film cast on an indium tin oxide (ITO) electrode exhibits excellent electrochromic properties; the color of the film disappears when a higher potential as compares to the redox potential of the metal ions is applied to the polymer film. In addition, multicolor electrochromic changes appear on introducing two types of metal ions to the polymer. Electrochromic solid-state devices are successfully fabricated by using these polymers. This paper is dedicated to Professor Takakazu Yamamoto in honor of his pioneering research efforts and accomplishments in the fields of organometallics and π-conjugated polymers.     

Synthesis of Tamoxifen-Artemisinin and Estrogen-Artemisinin Hybrids Highly Potent Against Breast and Prostate Cancer

In the search for new and effective treatments of breast and prostate cancer, a series of hybrid compounds based on tamoxifen, estrogens, and artemisinin were successfully synthesized and analyzed for their in vitro activities against human prostate (PC-3) and breast cancer (MCF-7) cell lines. Most of the hybrid compounds exhibit a strong anticancer activity against both cancer cell lines – for example, EC₅₀ (PC-3) down to 1.07 μM, and EC₅₀ (MCF-7) down to 2.08 μM – thus showing higher activities than their parent compounds 4-hydroxytamoxifen (afimoxifene, 7 ; EC₅₀=75.1 (PC-3) and 19.3 μM (MCF-7)), dihydroartemisinin ( 2 ; EC₅₀=263.6 (PC-3) and 49.3 μM (MCF-7)), and artesunic acid ( 3 ; EC₅₀=195.1 (PC-3) and 32.0 μM (MCF-7)). The most potent compounds were the estrogen-artemisinin hybrids 27 and 28 (EC₅₀=1.18 and 1.07 μM, respectively) against prostate cancer, and hybrid 23 (EC₅₀=2.08 μM) against breast cancer. These findings demonstrate the high potential of hybridization of artemisinin and estrogens to further improve their anticancer activities and to produce synergistic effects between linked pharmacophores.