Synthesis and characterization of novel phenyl‐substituted poly(p‐phenylene vinylene) derivatives

Two novel phenyl‐substituted poly(p‐phenylene vinylene) derivatives, poly{2‐[3′,4′‐(2″‐ethylhexyloxy)(3″,7″‐dimethyloctyloxy)benzene]‐1,4‐phenylenevinylene} (EDP‐PPV) and poly{2‐[3′,4′‐(2″‐ethylhexyloxy)(3″,7″‐dimethyloctyloxy)benzene]‐5‐methoxy‐1,4‐phenylenevinylene} (EDMP‐PPV), and their copolymer, poly{2‐[3′,4′‐(2″‐ethylhexyloxy)(3″,7″‐dimethyloctyloxy)benzene]‐1,4‐phenylene‐vinylene‐co‐2‐[3′,4′‐(2″‐ethylhexyloxy)(3″,7″‐dimethyloctyloxy)benzene]‐5‐methoxy‐1,4‐phenylenevinylene} (EDP‐co‐EDMP‐PPV; 4:1, 1:1, and 1:4), were successfully synthesized according to the Gilch route. The structures and properties of the monomers and the resulting conjugated polymers were characterized with ¹H‐NMR, ¹³C‐NMR, elemental analysis, gel permeation chromatography, thermogravimetric analysis, ultraviolet–visible absorption spectroscopy, and photoluminescence and electroluminescence (EL) spectroscopy. The EL polymers possessed excellent solubility in common solvents and good thermal stability with a 5% weight loss temperature of more than 380°C. The weight‐average molecular weights and polydispersity indices of EDP‐PPV, EDMP‐PPV, and EDP‐co‐EDMP‐PPV were 1.40–2.58 × 10⁵, and 1.19–1.52, respectively. Double‐layer light‐emitting diodes with the configuration of indium tin oxide/polymer/tris(8‐hydroxyquinoline)aluminum/Al devices were fabricated, and EDP‐co‐EDMP‐PPV (1:1) showed the highest EL performance and exhibited a maximum luminance of 1050 cd/m² at 19.5 V. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1259–1266, 2005     

Resistive switching characteristics of polyimides derived from 2,2′‐aryl substituents tetracarboxylic dianhydrides

2,2′‐Position aryl‐substituted tetracarboxylic dianhydrides including 2,2′‐bis(biphenyl)‐4,4′,5,5′‐biphenyl tetracarboxylic dianhydride and 2,2′‐bis[4‐(naphthalen‐1‐yl)phenyl)]‐4,4′,5,5′‐biphenyl tetracarboxylic dianhydride were synthesized. A new series of aromatic polyimides (PIs) were synthesized via a two‐step procedure from 3,3′,4,4′‐biphenyl tetracarboxylic dianhydride and the newly synthesized tetracarboxylic dianhydrides monomers reacting with 2,2′‐bis[4′‐(3″,4″,5″‐trifluorophenyl)phenyl]‐4,4′‐biphenyl diamine. The resulting polymers exhibited excellent organosolubility and thermal properties associated with T_g at 264 °C and high initial thermal decomposition temperatures (T_5%) exceeding 500 °C in argon. Moreover, the fabricated sandwich structured memory devices of Al/PI‐a/ITO was determined to present a flash‐type memory behaviour, while Al/PI‐b/ITO and Al/PI‐c/ITO exhibited write‐once read‐many‐times memory capability with different threshold voltages. In addition, Al/polymer/ITO devices showed high stability under a constant stress or continuous read pulse voltage of ? 1.0 V. Copyright © 2011 Society of Chemical Industry     

Novel magnesium and zinc porphyrazines containing galactose moieties: Synthesis via click reaction and characterization

In this study, galactose conjugated new magnesium and zinc porphyrazines were synthesized by the cyclotetramerization reaction of 2,3-bis[1-(2,2,7,7-tetramethyltetra-hydro-bis[1,3]dioxolo[4,5-b;4′,5′-d]pyran-5,methyl)-1H-[1,2,3]triazol-4-yl methylsulfanyl]-but 2-enedinitrile. This substituted dicyano compound was prepared via two different routes. One started from cis-1,2-dicyano-1,2-ethylenedithiolate disodium, [1-(2, 2, 7,7-tetramethyltetrahydrobis[1,3]dioxolo[4,5-b;4′,5′-d]pyran-5-yl-methyl)-1H-[1,2,3]triazo-l-4-yl]methanol and ended in a multi-step reaction sequence via Click procedures. The other reaction was between 5-azidomethyl-2,2,7,7-tetramethyltetrahydro-bis[1,3]dioxolo[4,5-b;4′,5′-d]pyran and (2Z)-2,3-bis(prop-2-yl-1-yl-thio)but-2-enedinitrile. A very soluble galactose linked magnesium porphyrazine derivative in common polar solvents and water was achieved by the deprotected isopropylidene groups in TFA and water media. It is first time, zinc porphyrazine complex has been achieved at one-step reaction by using Zn(BuO)₂ as template agent. The new compounds have been characterized by a combination of elemental analysis, ¹H, ¹³C NMR, IR, UV–vis and MS spectral data.     

Thia- and selenaheterocycles by a four-component reaction using elemental sulfur and selenium

The course of the four-component reactions of (2-benzimidazolyl) acetonitrile, carbondisulfide, isothiocyanate, and sulfur and selenium, respectively, is quite different. Whereas in the case of sulfur a tetracyclic [1,3]thiazolo[4′,5′:4,5]pyrimido[1,6-a]benzimidazol-2(3H)-thione is formed, a zwitterionic 7-(benzimidazolium-2-yl)-[1,2]thiaselenolo[2,3-b][1,2,4]thiaselenazole-6-thiolate (an azaselenadithiapentalene) is the product in the case of selenium. The structures of the products have been established by X-ray crystallography, and reaction mechanisms for their formation are proposed.     

Two-component,one-pot synthesis of pyrimido[1,2-b] [1,2,4,5]tetrazines

Derivatives containing the cyclohepta4′,5′thieno[2′,3′:4,5]pyrimido[1,2-b][1,2,4,5]-tetrazin-6-one system were prepared from the reaction of 3-amino-2-thioxo-1,2,3,5,6,7,8,9-octahydro-4H-cyclohepta[4,5]thieno[2,3-d]pyrimidin-4-one (5) or its 2-methylthio derivative 6 with hydrazonoyl chlorides 9. The mechanism of the studied reactions has been discussed and the biological activity of the isolated products has been evaluated.     

Palladium(II) Complexes of C2‐Bridged Chiral Diphosphines: Application to Enantioselective Carbonyl‐Ene Reactions

(11bR,11′bR)‐4,4′‐(1,2‐Phenylene)bis[4,5‐dihydro‐3H‐dinaphtho[2,1‐c:1′,2′‐e]phosphepin] [abbreviated as (R)‐BINAPHANE], (3R,3′R,4S,4′S,11bS,11′bS)‐4,4′‐bis(1,1‐dimethylethyl)‐4,4′,5,5′‐tetrahydro‐3,3′‐bi‐3H‐dinaphtho[2,1‐c:1′,2′‐e]phosphepin [(S)‐BINAPINE], (1S,1′S,2R,2′R)‐1,1′‐bis(1,1‐dimethylethyl)‐2,2′‐biphospholane [(S,S,R,R)‐TANGPHOS] and (2R,2′R,5R,5′R)‐1,1′‐(1,2‐phenylene)bis[2,5‐bis(1‐methylethyl)phospholane] [(R,R)‐i‐Pr‐DUPHOS] are C₂‐bridged chiral diphosphines that form stable complexes with palladium(II) and platinum(II) containing a five‐membered chelate ring. The Pd(II)‐BINAPHANE catalyst displayed good to excellent enantioselectivities with ee values as high as 99.0% albeit in low yields for the carbonyl‐ene reaction between phenylglyoxal and alkenes. Its Pt(II) counterpart afforded improved yields while retaining satisfactory enantioselectivity. For the carbonyl‐ene reaction between ethyl trifluoropyruvate and alkenes, the Pd(II)‐BINAPHANE catalyst afforded both good yields and extremely high enantioselectivities with ees as high as 99.6%. A comparative study on the Pd(II) catalysts of the four C₂‐bridged chiral diphosphines revealed that Pd(II)‐BINAPHANE afforded the best enantioselectivity. The ee values derived from Pd(II)‐BINAPHANE are much higher than those derived from the other three Pd(II) catalysts. A comparison of the catalyst structures shows that the Pd(II)‐BINAPHANE catalyst is the only one that has two bulky (R)‐binaphthyl groups close to the reaction site. Hence it creates a deep chiral space that can efficiently control the reaction behavior in the carbonyl‐ene reactions resulting in excellent enantioselectivity.     

Fluorinated polybenzimidazopyrrolones with excellent alkaline‐hydrolysis resistance

Two novel aromatic tetraamines containing bulky lateral phenyl unit and multiple trifluoromethyl groups, 1,1‐bis[4‐(3′,4′‐diaminophenoxy)phenyl]‐1‐(3″‐trifluoromethylphenyl)?2,2,2‐trifluoroethane (6FTA) and 1,1‐bis[4‐(3′,4′‐diaminophenoxy)phenyl]‐1‐[3″,5″‐bis(trifluoromethyl)phenyl]‐2,2,2‐trifluoroethane (9FTA) were synthesized and characterized. A series of fluorinated aromatic polybenzimidazopyrrolones (polypyrrolones, PPys) were synthesized via a two‐step polycondensation procedure. The inherent viscosities of the precursors, poly(amide amino acid) (PAAA), ranged from 0.39 dL/g to 0.54 dL/g. All the FPPys were amorphous. The freestanding FPPy films could be prepared, which exhibited good thermal stability with the glass transition temperature of 315–389°C, the temperatures of 5% weight loss (T_5%) of 497–535°C in nitrogen and residual weight retention at 700°C over 60%. All the FPPy films exhibited excellent alkaline‐hydrolysis resistance which retained their original shapes and toughness after boiling 7 days in 10% sodium hydroxide solution. Also after boiling 8 h in 10% sodium hydroxide solution, the tensile strength could retain as high as 56% of the original values. The alkaline‐hydrolysis resistance was much better than the polyimides which had similar chemical structures. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40041.     

Synthesis of polyazaheterocycles by Michael addition of CH acids to α,β-unsaturated nitriles. Synthesis of pyrido[1,2-a]benzimidazole and pyrimido[5′,4′: 5,6]pyrido[1,2-a]benzimidazole derivatives

Addition of 1H-benzimidazole-2-carbonitrile ( 1 ) to arylidenemalononitrile ( 2 ) gave 1-amino-3-aryl pyrido[1,2-a]benzimidazole-2,4-dicarbonitrile ( 3 ), 2-aryl-benzimidazole ( 4 ) and 1H-benzimidazole-2-acetonitrile,α-(arylmethylene) ( 5 ). Compounds ( 3 ) reacted with formamide yielding 4-amino-5-aryl pyrimido[5′,4′: 5,6]pyrido[1,2-a]benzimidazole ( 6 ).     

Synthesis and photovoltaic device studies of azo‐linked low‐bandgap polymers

We report the synthesis of a series of new polymers containing azo linkage as a part of the main chain. The monomer 1,2‐bis(7‐bromo‐9,9‐dioctyl‐9H ‐fluoren‐2‐yl)diazene was synthesized using a precursor approach which avoids non‐selective bromination and was copolymerized with various donor or acceptor units. The homopolymer poly[1,2‐bis(9,9‐dioctyl‐9H ‐fluoren‐2‐yl)diazene] ( P1 ) as well as the copolymers poly[1‐(9,9‐dioctyl‐9H ‐fluoren‐2‐yl)‐2‐(9,9,9′,9′‐tetraoctyl‐9H ,9′H ‐[2,2′‐bifluoren]‐7‐yl)diazene] ( P2 ), poly[1‐(9,9‐dioctyl‐7‐(4‐octylthiophen‐2‐yl)‐9H ‐fluoren‐2‐yl)‐2‐(9,9‐dioctyl‐9H ‐fluoren‐2‐yl)diazene] ( P3 ) and poly[4‐(7‐((9,9‐dioctyl‐9H ‐fluoren‐2‐yl)diazenyl)‐9,9‐dioctyl‐9H ‐fluoren‐2‐yl)benzo[c ][1,2,5]thiadiazole] ( P4 ) were synthesized by Suzuki polymerization. The copolymers poly[1‐(7‐(4,4‐dioctyl‐4H ‐cyclopenta[1,2‐b :5,4‐b ′]dithiophen‐2‐yl)‐9,9‐dioctyl‐9H ‐fluoren‐2‐yl)‐2‐(9,9‐dioctyl‐9H ‐fluoren‐2‐yl)diazene] ( P5 ) and poly[4‐(5‐(7‐((9,9‐dioctyl‐9H ‐fluoren‐2‐yl)diazenyl)‐9,9‐dioctyl‐9H ‐fluoren‐2‐yl)‐4‐octylthiophen‐2‐yl)‐7‐(4‐octylthiophen‐2‐yl)benzo[c ][1,2,5]thiadiazole] ( P6 ) were synthesized by direct arylation polymerization reaction. Polymers synthesized using the direct arylation method show good molecular weight, with absorption maxima in the range 500 to 532 nm. P5 and P6 possess low optical bandgaps of 1.81 and 1.86 eV, respectively. A power conversion efficiency of 0.53% with open circuit voltage of 0.53 V, short circuit current density of 3.1 mA cm^?2 and fill factor of 29% has been achieved with C71‐PCBM as acceptor in bulk heterojunction solar cells fabricated with P5 as donor. © 2016 Society of Chemical Industry     

Synthesis and spectroelectrochemistry of dithieno(3,2‐b:2′,3′‐d)pyrrole derivatives

New π‐conjugated polymers containing dithieno(3,2‐b:2′,3′‐d)pyrrole (DTP) were successfully synthesized via electropolymerization. The effect of structural differences on the electrochemical and optoelectronic properties of the 4‐[4H‐dithieno(3,2‐b:2′,3′‐d)pyrrol‐4‐yl]aniline (DTP–aryl–NH₂), 10‐[4H‐dithiyeno(3,2‐b:2′,3′‐d)pirol‐4‐il]dekan‐1‐amine (DTP–alkyl–NH₂), and 1,10‐bis[4H‐dithieno(3,2‐b:2′,3′‐d)pyrrol‐4‐yl] decane (DTP–alkyl–DTP) were investigated. The corresponding polymers were characterized by cyclic voltammetry, NMR (¹H‐NMR and ¹³C‐NMR), and ultraviolet–visible spectroscopy. Changes in the electronic nature of the functional groups led to variations in the electrochemical properties of the π‐conjugated systems. The electroactive polymer films revealed redox couples and exhibited electrochromic behavior. The replacement of the DTP–alkyl–DTP unit with DTP–aryl–NH₂ and DTP–alkyl–NH₂ resulted in a lower oxidation potential. Both the poly(10‐(4H‐Dithiyeno[3,2‐b:2′,3′‐d]pirol‐4‐il)dekan‐1‐amin) (poly(DTP–alkyl–NH₂)) and poly(1,10‐bis(4H‐dithieno[3,2‐b:2′,3′‐d]pyrrol‐4‐yl) decane) (poly(DTP–alkyl–DTP)) films showed multicolor electrochromism and also fast switching times (<1 s) in the visible and near infrared regions. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40701.     

Synthesis of pyrazolo[4′,3′:5,6]pyrido[1,2-a]benzimidazole derivatives and study of their fluorescence properties

Synthesis of pyrazolo[4′,3′ :-5,6′pyrido]1,2-a benzimidazoles was achieved by the condensation of 1-chloro-2-formyl-3-methyl pyrido[1,2-a]benzimidazole-4-carbonitrile and 1-chloro-3-methyl pyrido[1,2-a]benzimidazole-2,4-dicarbonitrile with hydrazine hydrate and phenyl hydrazine. The fluorescence properties of the resulting compounds were studied. Some of the compounds when applied on polyester fibres as fluorescent brighteners gave excellent results.     

Crystallography and Structure–Property Relationships in 2,2′,2″,2′′′,4,4′,4″,4′′′,6,6′,6″,6′′′‐Dodecanitro‐1,1′ : 3′1″ : 3″,1′′′‐ Quaterphenyl (DODECA)

X‐ray crystallographic study of 2,2′,2″,2′′′,4,4′,4″,4′′′,6,6′,6″,6′′′‐dodecanitro‐1,1′ : 3′1″ : 3″,1′′′‐quaterphenyl (DODECA) has been carried out. Nonbonding interatomic distances of oxygen atoms inside of all the nitro groups are shorter than those corresponding to the intermolecular contact radii for oxygen. By means of the DFT B3LYP/6‐31(d, p) method a difference of 136 kJ mol⁻¹ between the X‐ray and DFT structures of DODECA was found. The bearer of the highest initiation reactivity in its molecule in solid phase should be the nitro group at 4′′′‐position, in contrast to those at 2′‐ or 2″‐positions in its isolated molecule. The most reactive nitro group in the DODECA molecule can be well specified by the relationship between net charges on nitro groups and charges on their nitrogen atoms, both of them for the X‐ray structure. The ¹⁵N chemical shift, corresponding to this nitro group for the initiation by impact and shock, correlates very well with these shifts of the reaction centers of the other six “genuine” polynitro arenes.     

Crystallography and Structure–Property Relationships of 2,2″,4,4′,4″,6,6′,6″‐Octanitro‐1,1′ : 3′,1″‐Terphenyl (ONT)

An X‐ray crystallographic study of 2,2″,4,4′,4″,6,6′,6″‐octanitro‐1,1′ : 3′,1″‐terphenyl (ONT) has been carried out. The dihedral angles between benzene rings vary from 84.9° to 89.4°. Nonbinding interatomic distances of oxygen atoms inside all the nitro groups are shorter than the intermolecular contact radii for oxygen. On the basis of the DFT B3LYP/6‐31(d, p) method it was found that the difference between the X‐ray structure in the solid phase and DFT result for the gas phase is 98 kJ mol⁻¹, and the bearer of the highest initiation reactivity of the ONT molecule in the solid phase should be the nitro group at 4″‐position, in contrast to those at 4′‐ or 6′‐position that play this role in the isolated molecule. It has been stated that the nitro groups at the reaction centers of the ONT molecule are relatively well specified by their ¹⁵N NMR chemical shifts.     

Gold(I)‐Catalyzed Cascade for Synthesis of Pyrrolo[1,2‐a:2′,1′‐c]‐/Pyrido[2,1‐c]pyrrolo[1,2‐a]quinoxalinones

An efficient and convenient method was developed for the one‐pot construction of the complex polycyclic heterocycles pyrrolo[1,2‐a:2′,1′‐c]‐/pyrido[2,1‐c]pyrrolo[1,2‐a]quinoxalinones from two simple starting materials via a gold(I)‐catalyzed domino reaction. This strategy presents an atom economical and environmentally friendly transformation, in which two new C N bonds and one new C C bond are formed in a one‐pot reaction process.     

Pyrido[2,3-d]pyrimidine-2,7-dithiol in heterocyclic synthesis: Synthesis and characterization of several new fused pyridopyrimidine heterocycles

Pyridine-2(1H)-thione 1 reacted with phenyl isothiocyanate to give pyrido[2,3-d]pyrimidine derivative 3. Compound 3 reacted with halogen containing compounds 4a–d and methyl iodide in dimethylformamide/potassium hydroxide solution at room temperature to give 2,7-bisalkylthiopyrido[2,3-b]pyrimidine derivatives 5a–d and 9, respectively. Compounds 5a–d could be cyclized into thienopyrido[2,3-d]pyrimidine derivatives 6a–d by boiling with ethanolic potassium hydroxide solution. Compound 6a reacted with acetic anhydride or formic acid and gave the corresponding pyrimido[4″,5″:4′,5′]thieno[3′,2′:5,6]pyrido[2,3-d]pyrimidine derivatives 8a,b. Compound 9 reacted with hydrazine hydrate to yield pyrazolo[4′,3′:5,6]pyrido[2,3-d]pyrimidine derivative 11 which could be reacted with nitrous acid and dimethylformamide-dimethylacetal (DMF-DMA) and gave the final isolable products corresponding to the pyrazolo[4′,3′:5,6]pyrido[2,3-d]tetrazolo-[5,1-b]pyrimidine and pyrimido[1″,2″:1′,5′]pyrazolo[4′,3′:5,6]pyrido[2,3-d]1 Abbas, A. A., Elneairy, M. A.A. and Mabkhot, Y. N. 2001. J. Chem. Res.(S), 4: 124[Crossref] , [Google Scholar] 2 Riad, B. Y., Negem, A. M., Abdou, S. E. and Daboun, H. A. 1987. Heterocycles, 26: 205[Crossref], [Web of Science ®] , [Google Scholar] 4 Gad-Elkareem, M. A.M. and Abedelhamid, A. O. 2004. Afinidad, 61(513): 427[Web of Science ®] , [Google Scholar]triazolo-[4,3-b] pyrimidine derivatives 13 and 17, respectively. Compound 11 also reacted with some β-dicarbonyl compounds such as acetylacetone (18) and ethyl acetoacetate (20) to yield the corresponding pyrimido[1″,2″:1′,5′]pyrazolo[4′,3′:5,6]pyrido[2,3-d]pyrimidine derivatives 19 and 21, respectively. Finally, compound 11 reacted with chloroacetyl chloride (22) to give the corresponding imidazo[1″′,2″′:1″,5″]pyrazolo[4″,3″:5′,6′]pyrido[3′,2′:5,6]pyrimido[2,1-c]1 Abbas, A. A., Elneairy, M. A.A. and Mabkhot, Y. N. 2001. J. Chem. Res.(S), 4: 124[Crossref] , [Google Scholar] 2 Riad, B. Y., Negem, A. M., Abdou, S. E. and Daboun, H. A. 1987. Heterocycles, 26: 205[Crossref], [Web of Science ®] , [Google Scholar] 4 Gad-Elkareem, M. A.M. and Abedelhamid, A. O. 2004. Afinidad, 61(513): 427[Web of Science ®] , [Google Scholar]triazine derivative 23.     

Cyclization of 1,4‐Phenylenediacrylic Acid with Thionyl Chloride and Subsequent Suzuki–Miyaura Reactions Revisited. The Products are Benzo[1,2‐b;5,6‐b′]dithiophenes and not Benzo[1,2‐b;4,5‐b′]dithiophenes

The reaction of 1,4‐phenylenediacrylic acid with thionyl chloride was reinvestigated. In earlier reports [Liebigs Ann. Chem. 1980 , 1172; Heterocycles 1995 , 41, 2691; Adv. Synth. Catal. 2009 , 351, 2683] it was claimed that 3,7‐dichlorobenzo[1,2‐b;4,5‐b′]dithiophenes were formed in these reactions. Herein, we provide unambiguous evidence that the assignment of these structures is wrong and that, in contrast, 3,6‐dichlorobenzo[1,2‐b;5,6‐b′]dithiophenes are formed. As a consequence, the structures of these parent molecules and of numerous aryl‐substituted derivatives prepared by Pd‐catalyzed cross‐coupling reactions have to be revised. As many of these dithiophenes were reported to show interesting optical, thermal and electronic properties, the theoretical explanations for these properties have to be reconsidered in the light of the corrected structures reported herein. Our structural assignments are based on X‐ray crystal structure analyses of the parent molecules and on NMR spectroscopic studies of the first unsymmetrical derivatives. Besides, mechanistic investigations based on quantum chemical calculations have been carried out which support the formation of the 3,6‐dichlorobenzo[1,2‐b;5,6‐b′]dithiophene isomers.     

Pd‐complex‐catalyzed synthesis of oligomers having a recurring benzodiazaborole unit in the main chain

BACKGROUND: Rigid‐rod oligomers and polymers comprising a recurring benzodiazaborole unit show high thermal stability and intriguing optical and electrochemical properties due to the expanded electron system through the B? C and B? N bonds in the main chain by the use of the p_z orbital on boron. However, the conventional method for the preparation of these oligomers and polymers often requires polycondensation under severe conditions. In this study, we report the synthesis of oligomers comprising a recurring benzodiazaborole unit using the Stille reaction under mild conditions. In addition, we describe their chemical properties and solid‐state structures. RESULTS: The reaction of 3,3′‐diaminobenzidine with 4‐bromophenylboronic acid and benzeneboronic acid yielded 2,2′‐bis(4‐bromophenyl)‐2,3,2′,3′‐tetrahydro‐1H,1′H‐[5,5′]bi(benzo[1,3,2]diazaborolyl) (1) and 2,2′‐biphenyl‐2,3,2′,3′‐tetrahydro‐1H,1′H‐[5,5′]bi(benzo[1,3,2]diazaborolyl), respectively. Pd‐complex‐catalyzed polycondensation of 1 with bis(tributyltin) and bis(tributylstannyl)acetylene in N,N‐dimethylformamide provided oligomers comprising a recurring benzodiazaborole unit in 98 and 97% yields, respectively. CONCLUSION: The oligomers comprising a recurring benzodiazaborole unit were obtained under mild reaction conditions in high yields. The expansion of the electron system through the B? C and B? N bonds of the oligomers was confirmed by UV‐visible spectroscopy. The oligomers were photoluminescent in solution and electrochemically active in a film, and they assumed self‐assembled stacked structures in the solid state. Copyright © 2008 Society of Chemical Industry     

Synthesis,antimicrobial, anti-inflammatory and antioxidant activity of novel Spiro (imidazo[4′,5′:4,5′]benzo[1,2-e][1, 4] thiazepine)-9,3′-indolines

An efficient synthesis of novel spiro(imidazo[4′,5′:4,5′]benzo[1,2-e][1, 4]thiazepine)-9,3′-indolines has been accomplished from 5-amino-2-mercapto benzimidazole, istains and mercapto acetic acid. Compounds 6 were characterized by IR, ¹H NMR, ¹³C NMR and mass spectral data. The title compounds 6a–6e were evaluated for their antimicrobial, anti-inflammatory and antioxidant activity. Compounds 6a–6e exhibited significant antimicrobial activity, and as potent anti-inflammatory and antioxidant activities as that shown by standard drugs.     

Synthesis and Biological Evaluation of Pyrrolo[2,1‐f][1,2,4]triazine C‐Nucleosides with a Ribose, 2′‐Deoxyribose,and 2′,3′‐Dideoxyribose Sugar Moiety

The synthesis of hitherto unknown pyrrolo[2,1‐f][1,2,4]triazine C‐nucleosides is described. Structural variations (chlorine, bromine, iodine, and cyano groups) were introduced at position 7 of 4‐aza‐7,9‐dideazaadenine. In addition, pyrrolo[2,1‐f][1,2,4]triazine C‐nucleosides bearing a 2′‐deoxy‐, 2′,3′‐dideoxy‐, and 2′,3′‐dehydrodideoxyribose moiety were also prepared. Among these analogues, the pyrrolo[2,1‐f][1,2,4]triazine C‐ribonucleosides with either a hydrogen atom or cyano group at position 7 of the nucleobase displayed potent cytotoxic activity in a panel of various cancer cell lines.     

Poly(propylene)-based Films Modified with a Tetracationic Phthalocyanine with Applications in Photodynamic Inactivation of Candida albicans

Photoactive films based on polymer-like poly(propylene) were generated and utilized as support of zinc(II)tetramethyltetrapyridino[2,3-b:2′,3′-g:2″,3″-l:2″′,3″′-q]porphyrazinium salt (ZnTM2,3PyPz). Using a photograft polymerization of acrylic acid, the poly(propylene) film was functionalized with carboxyl groups (PP-g-PAAc), which attached ZnTM2,3PyPz by electrostatic bond to form PP-g-PAAc-Pc films. In vitro investigations indicated that PP-g-PAAc-Pc films produced photodynamic inactivation of Candida albicans cells, mainly mediated by a contribution of type II process. According to the results, the photodynamic activity produced by the PP-g-PAAc-Pc film and visible light irradiation can successfully inactivate C. albicans deposited on the surface of the films.