Copper‐Assisted Click Reactions for Activity‐Based Proteomics: Fine‐Tuned Ligands and Refined Conditions Extend the Scope of Application

Copper‐catalysed alkyne–azide 1,3‐dipolar cycloaddition (CuAAC) is the predominantly used bioconjugation method in the field of activity‐based protein profiling (ABPP). Several limitations, however, including conversion efficiency, protein denaturation and buffer compatibility, restrict the scope of established procedures. We introduce an ABPP customised click methodology based on refined CuAAC conditions together with new accelerating copper ligands. A screen of several triazole compounds revealed the cationic quaternary {3‐[4‐({bis[(1‐tert‐butyl‐1H‐1,2,3‐triazol‐4‐yl)methyl]amino}methyl)‐1H‐1,2,3‐triazol‐1‐yl]propyl}trimethylammonium trifluoroacetate (TABTA) to be a superior ligand. TABTA exhibited excellent in vitro conjugation kinetics and optimal ABPP labelling activity while almost exclusively preserving the native protein fold. The application of this CuAAC‐promoting system is amenable to existing protocols with minimal perturbations and is even compatible with previously unusable buffer systems such as Tris ? HCl.     

6,7‐Dimethoxy‐2‐{2‐[4‐(1H‐1,2,3‐triazol‐1‐yl)phenyl]ethyl}‐1,2,3,4‐tetrahydroisoquinolines as Superior Reversal Agents for P‐Glycoprotein‐Mediated Multidrug Resistance

P‐glycoprotein (P‐gp)‐mediated multidrug resistance (MDR) is a major obstacle for successful cancer chemotherapy. Based on our previous study, 17 novel compounds with the 6,7‐dimethoxy‐2‐{2‐[4‐(1H‐1,2,3‐triazol‐1‐yl)phenyl]ethyl}‐1,2,3,4‐tetrahydroisoquinoline scaffold were designed and synthesized. Among them, 2‐[(1‐{4‐[2‐(6,7‐dimethoxy‐3,4‐dihydroisoquinolin‐2(1H)‐yl)ethyl]phenyl}‐1H‐1,2,3‐triazol‐4‐yl)methoxy]‐N‐(p‐tolyl)benzamide (compound 7 h ) was identified as a potent modulator of P‐gp‐mediated MDR, with high potency (EC₅₀=127.5±9.1 nM ), low cytotoxicity (TI>784.3), and long duration (>24 h) in reversing doxorubicin (DOX) resistance in K562/A02 cells. Compound 7 h also enhanced the effects of other MDR‐related cytotoxic agents (paclitaxel, vinblastine, and daunorubicin), increased the accumulation of DOX and blocked P‐gp‐mediated rhodamine 123 efflux function in K562/A02 MDR cells. Moreover, 7 h did not have any effect on cytochrome (CYP3A4) activity. These results indicate that 7 h is a relatively safe modulator of P‐gp‐mediated MDR that has good potential for further development.     

Potent,Metabolically Stable 2‐Alkyl‐8‐(2H‐1,2,3‐triazol‐2‐yl)‐9H‐adenines as Adenosine A2A Receptor Ligands

Inhibition of adenosine A_2A receptors has been shown to elicit a therapeutic response in preclinical animal models of Parkinson’s disease (PD). We previously identified the triazolo‐9H‐purine, ST1535, as a potent A_2AR antagonist. Studies revealed that ST1535 is extensively hydroxylated at the ω‐1 position of the butyl side chain. Here, we describe the synthesis and evaluation of derivatives in which the ω‐1 position has been substituted (F, Me, OH) in order to block metabolism. The stability of the compounds was evaluated in human liver microsomes (HLM), and the affinity for A_2AR was determined. Two compounds, (2‐(3,3‐dimethylbutyl)‐9‐methyl‐8‐(2H‐1,2,3‐triazol‐2‐yl)‐9H‐purin‐6‐amine ( 3 b ) and 4‐(6‐amino‐9‐methyl‐8‐(2H‐1,2,3‐triazol‐2‐yl)‐9H‐purin‐2‐yl)‐2‐methylbutan‐2‐ol ( 3 c ), exhibited good affinity against A_2AR (K_i=0.4 nM and 2 nM , respectively) and high in vitro metabolic stability (89.5 % and 95.3 % recovery, respectively, after incubation with HLM for two hours).     

Synthesis of isoelectronic polyazomethine and poly(arylene vinylene) by a palladium‐catalyzed Suzuki coupling method

Two fully conjugated copolymers containing 2,7‐(9,9‐dioctyl) fluorene and 3,6‐(N‐hexyl‐9H‐carbazole) disubstituted rings and arylene vinylene or azomethine units in the main chain were synthesized through a palladium‐catalyzed Suzuki coupling method of 2,7‐bis(4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolan‐2‐yl)‐9,9‐dioctyl fluorene with 1,4‐bis(6‐bromo‐N‐hexyl‐9H‐carbazole‐3‐yl vinyl) benzene or N,N‐bis(6‐bromo‐N‐hexyl‐9H‐carbazole‐3‐yl methylidene) 1,4‐phenylenediamine. Bisbromine arylene vinylene and arylenazomethine monomers were synthesized by condensation of 3‐formyl‐N‐hexyl‐6‐bromo carbazole with tetraethyl‐p‐xylylene diphosphonate or 1,4‐phenylenediamine. Copolymers were characterized by FTIR, ¹H‐NMR, DSC, UV‐visible and photoluminescence methods. Copyright © 2005 Society of Chemical Industry     

From Mono‐Triazolium Salt to Bis‐Triazolium Salt: Improvement of the Asymmetric Intermolecular Benzoin Condensation

A solution to the long‐standing challenge of developing a highly effective method for the enantioselective intermolecular benzoin condensation of aromatic aldehydes is described. The chiral bis‐bicyclic triazolium salt – 1,3‐bis{(S)‐5‐benzyl‐6,8‐dihydro‐5H‐[1,4]oxazino[2,1‐c][1,2,4]triazol‐2‐ium‐2‐yl}benzene dichloride [(S)‐ 5a‐1 ] is currently the most efficient precatalyst for the asymmetric variant of the benzoin condensation.     

Glucocerebrosidase Enhancers for Selected Gaucher Disease Genotypes by Modification of α‐1‐C‐Substituted Imino‐D‐xylitols (DIXs) by Click Chemistry

A series of hybrid analogues was designed by combination of the iminoxylitol scaffold of parent 1C9‐DIX with triazolylalkyl side chains. The resulting compounds were considered potential pharmacological chaperones in Gaucher disease. The DIX analogues reported here were synthesized by CuAAC click chemistry from scaffold 1 (α‐1‐C‐propargyl‐1,5‐dideoxy‐1,5‐imino‐D ‐xylitol) and screened as imiglucerase inhibitors. A set of selected compounds were tested as β‐glucocerebrosidase (GBA1) enhancers in fibroblasts from Gaucher patients bearing different genotypes. A number of these DIX compounds were revealed as potent GBA1 enhancers in genotypes containing the G202R mutation, particularly compound DIX‐28 (α‐1‐C‐[(1‐(3‐trimethylsilyl)propyl)‐1H‐1,2,3‐triazol‐4‐yl)methyl]‐1,5‐dideoxy‐1,5‐imino‐D ‐xylitol), bearing the 3‐trimethylsilylpropyl group as a new surrogate of a long alkyl chain, with approximately threefold activity enhancement at 10 nM . Despite their structural similarities with isofagomine and with our previously reported aminocyclitols, the present DIX compounds behaved as non‐competitive inhibitors, with the exception of the mixed‐type inhibitor DIX‐28.     

A DFT Study on the Structures and Energies of Isomers of 4‐Amino‐1,3‐dinitro‐1,2,4‐triazol‐5‐one‐2‐oxide: New High Energy Density Compounds

Isomers of 4‐amino‐1,3‐dinitrotriazol‐5‐one‐2‐oxide (ADNTONO) are of interest in the contest of insensitive explosives and were found to have true local energy minima at the DFT‐B3LYP/aug‐cc‐pVDZ level. The optimized structures, vibrational frequencies and thermodynamic values for triazol‐5‐one N‐oxides were obtained in their ground state. Kamlet‐Jacob equations were used to evaluate the performance properties. The detonation properties of ADNTONO (D=10.15 to 10.46 km s⁻¹, P=50.86 to 54.25 GPa) are higher compared with those of 1,1‐diamino‐2,2‐dinitroethylene (D=8.87 km s⁻¹, P=32.75 GPa), 5‐nitro‐1,2,4‐triazol‐3‐one (D=8.56 km s⁻¹, P=31.12 GPa), 1,2,4,5‐tetrazine‐3,6‐diamine‐1,4‐dioxide (D=8.78 km s⁻¹, P=31.0 GPa), 1‐amino‐3,4,5‐trinitropyrazole (D=9.31 km s⁻¹, P=40.13 GPa), 4,4′‐dinitro‐3,3′‐bifurazan (D=8.80 km s⁻¹, P=35.60 GPa) and 3,4‐bis(3‐nitrofurazan‐4‐yl)furoxan (D=9.25 km s⁻¹, P=39.54 GPa). The  NH₂ group(s) appears to be particularly promising area for investigation since it may lead to two desirable consequences of higher stability (insensitivity), higher density, and thus detonation velocity and pressure.     

Highly trans‐1,4‐specific polymerization of 1,3‐butadiene catalyzed by [2,6‐bis{(4S)‐ (−)‐isopropyl‐2‐oxazolin‐2‐yl}pyridine] chromium complex activated with modified methylaluminoxane

Chromium complexes with N,N,N‐tridentate ligands, LCrCl₃ (L = 2,6‐bis{(4S)‐(?)‐isopropyl‐2‐oxazolin‐2‐yl}pyridine ( 1 ), 2,2′:6′,2″‐terpyridine ( 2 ), and 4,4′,4″‐tri‐tert‐butyl‐2,2′:6′,2″‐terpyridine ( 3 )), were prepared. The structures of 1 and 2 were determined by X‐ray crystallography. Upon activation with modified methylaluminoxane (MMAO), 1 catalyzed the polymerization of 1,3‐butadiene, while 2 and 3 was inactive. The obtained poly(1,3‐butadiene) obtained with 1 ‐MMAO was found to have completely trans‐1,4 structure. The 1 ‐MMAO system also showed catalytic activity for the polymerization of isoprene to give polyisoprene with trans‐1,4 (68%) and cis‐1,4 (32%) structure. Copyright © 2011 Society of Chemical Industry     

Synthesis,characterization, and in vitro drug release study of 3‐arm poly‐β‐alanine

Synthesis of three arms star‐shaped poly‐β‐alanine (3‐b‐ala) based on tri(prop‐2‐yn‐1‐yl) benzene‐1,3,5‐tricarboxylate (TBT) and azido terminated poly‐β‐alanine (N₃‐P‐ala) was performed using click reaction. TBT was synthesized by nucleophilic substitution reaction between propargyl alcohol and 1,3,5‐benzenetricarbonyltrichloride. For the first time, N₃‐P‐ala was synthesized through anionic polymerization of acrylamide using sodium azide as an initiator. TBT was characterized by FT‐IR and ¹HNMR. N₃‐p‐ala was characterized by FT‐IR, GPC, and ¹HNMR and 3‐b‐ala was characterized by FT‐IR, GPC, ¹HNMR, TGA, and XRD. The synthesized 3‐b‐ala was used for drug loading and releasing studies. Polymer loaded drug (3‐b‐ala‐D) hybrid was used in in vitro studies of drug (Diclofenac sodium) release in phosphate buffer solution (PBS) at 37 ± 0.5°C and pH 7.4. The drug loading and releasing studies were analyzed by UV‐visible spectrophotometer. 3‐b‐ala‐D was examined by AFM to analyze the surface morphology and roughness. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42124.     

Energetic Salts of 5‐(5‐Azido‐1H‐1,2,4‐triazol‐3‐yl)tetrazole

Several metal and nitrogen‐rich salts of the recently presented 5‐(5‐azido‐1H‐1,2,4‐triazol‐3‐yl)tetrazole (AzTT), including silver ( 1 ), copper(I) ( 2 ), potassium ( 3 ), cesium ( 4 ), copper(II) ( 7 ), ammonium ( 8 ), and guanidinium ( 9 ), as well as the respective double‐salts of 3 , 4 , 8 and 9 , were prepared and well characterized by IR and multinuclear (¹H, ¹³C, ¹⁴N) NMR spectroscopy, DSC, mass spectrometry, elemental analysis and one ( 4 ) additionally by single‐crystal X‐ray diffraction. The sensitivities towards impact, friction and electrostatic discharge were determined according to BAM standards, revealing most of the metal salts as highly sensitive and the nitrogen‐rich salts as insensitive. The metal salts were further tested for their ability of being primary explosives.     

A water‐soluble supramolecular‐structured photoinitiator between methylated β‐cyclodextrin and 2,2‐dimethoxy‐2‐phenylacetophenone

A water‐soluble supramolecular‐structured photoinitiator (SSPI) was synthesized by supramolecular self‐assembling between methylated β‐cyclodextrin (MβCD) and hydrophobic 2,2‐dimethoxy‐2‐phenylacetophenone (DMPA). The structure of SSPI was characterized by X‐ray diffraction, FTIR, ¹H NMR, UV–vis, and fluorescence spectra. The results indicated that MβCD and DMPA had formed 1 : 1 inclusion complex in methanol solution. The binding constant (K) for the complex was 7.51 × 10²M^?1. SSPI could be dissolved in water easily and its water‐solubility was 15.3 g/100 mL. SSPI was the more efficient photoinitiator than DMPA for the photopolymerization of acrylamide (AM) in homogeneous aqueous system. The conversion for photopolymerization of trimethylolpropane triacrylate system initiated by SSPI was similar to that initiated by DMPA. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Bi‐Spectral IRCM‐Flare Formulations based on Tetrazole‐Derivatives

The spectral performance, sensitiveness to ignition stimuli and burning rate of bi‐spectral flare formulations based on tetrazole containing fuels, 5‐phenyl‐1H‐tetrazole, 5,5′‐(1,4‐phenylene)bis(1H‐tetrazole) and 5‐(4‐nitro‐phenyl)‐1H‐tetrazole, utilizing potassium perchlorate as the oxidizer, are reported. The formulation based on 5‐(4‐nitro‐phenyl)‐1H‐tetrazole yielded the highest spectral efficiency in the β‐band (44.1 J g⁻¹ sr⁻¹). The formulation based on 5‐phenyl‐1H‐tetrazole gave the highest color ratio (θ_β/α=6.8) and was the least sensitive.     

Aryl and heteroaryl azo dyes derived from 6, 8‐dichloro‐4‐hydroxyquinolin‐2 (1H)‐one: synthesis,characterisation, solvatochromism and spectroscopic properties

In this research study, 6, 8‐dichloro‐4‐hydroxyquinolin‐2(1H)‐one was prepared by the thermal cyclocondensation of 2‐(2, 4‐dichlorophenylcarbamoyl) acetic acid or N, N?‐bis(2,4‐dichlorophenyl)malonamide at 140‐150°C in polyphosphoric acid, resulting in a yield of 48%. This compound was then coupled with a series of diazonium salts derived from aromatic and heteroaromatic amines for synthesis of the corresponding azo dyes. The structures of the compounds were confirmed using elemental analysis as well as ultraviolet‐visible, Fourier Transform‐infrared and proton nuclear magnetic resonance spectroscopy. The effects of organic solvents with different polarities, pH values and substituents of the diazotising components on the maximum absorption wavelength of the colorants were discussed and evaluated in detail. The acidity constants (pK_a) of the dyes were also determined using the spectrophotometric method in an ethanol‐water mixture (80:20, v/v) at 20‐23°C.     

Synthesis,Crystal Structure,and Thermal Behavior of 3‐(4‐Aminofurazan‐3‐yl)‐4‐(4‐nitrofurazan‐3‐yl)furazan (ANTF)

The energetic material 3‐(4‐aminofurazan‐3‐yl)‐4‐(4‐nitrofurazan‐3‐yl)furazan (ANTF) with low melting‐point was synthesized by means of an improved oxidation reaction from 3,4‐bis(4′‐aminofurazano‐3′‐yl)furazan. The structure of ANTF was confirmed by ¹³C NMR spectroscopy, mass spectrometry, and the crystal structure was determined by X‐ray diffraction. ANTF crystallized in monoclinic system P2₁/c, with a crystal density of 1.785 g cm⁻³ and crystal parameters a=6.6226(9) Å, b=26.294(2) Å, c=6.5394(8) Å, β=119.545(17)°, V=0.9907(2) nm³, Z=4, μ=0.157 mm⁻¹, F(000)=536. The thermal stability and non‐isothermal kinetics of ANTF were studied by differential scanning calorimetry (DSC) with heating rates of 2.5, 5, 10, and 20 K min⁻¹. The apparent activation energy (E_a) of ANTF calculated by Kissinger's equation and Ozawa's equation were 115.9 kJ mol⁻¹ and 112.6 kJ mol⁻¹, respectively, with the pre‐exponential factor lnA=21.7 s⁻¹. ANTF is a potential candidate for the melt‐cast explosive with good thermal stability and detonation performance.     

Automated Synthesis of (rac)‐, (R)‐, and (S)‐[18F]Epifluorohydrin and Their Application for Developing PET Radiotracers Containing a 3‐[18F]Fluoro‐2‐hydroxypropyl Moiety

To introduce the 3‐[¹⁸F]fluoro‐2‐hydroxypropyl moiety into positron emission tomography (PET) radiotracers, we performed automated synthesis of (rac)‐, (R)‐, and (S)‐[¹⁸F]epifluorohydrin ([¹⁸F] 1 ) by nucleophilic displacement of (rac)‐, (R)‐, or (S)‐glycidyl tosylate with ¹⁸F^? and purification by distillation. The ring‐opening reaction of (R)‐ or (S)‐[¹⁸F] 1 with phenol precursors gave enantioenriched [¹⁸F]fluoroalkylated products without racemisation. We then synthesised (rac)‐, (R)‐, and (S)‐ 2‐{5‐[4‐(3‐[¹⁸F]fluoro‐2‐hydroxypropoxy)phenyl]‐2‐oxobenzo[d]oxazol‐3(2H)‐yl}‐N‐methyl‐N‐phenylacetamide ([¹⁸F] 6 ) as novel radiotracers for the PET imaging of translocator protein (18 kDa) and showed that (R)‐ and (S)‐[¹⁸F] 6 had different radioactivity uptake in mouse bone and liver. Thus, (rac)‐, (R)‐, and (S)‐[¹⁸F] 1 are effective radiolabelling reagents and can be used to develop PET radiotracers by examining the effects of chirality on their in vitro binding affinities and in vivo behaviour.     

Phosphorus‐containing poly(ester‐imide)–polydimethylsiloxane copolymers

New phosphorus‐containing poly(ester‐imide)‐polydimethylsiloxane copolymers were prepared by solution polycondensation of 1,4‐[2‐(6‐oxido‐6H‐dibenz < c,e > < 1, 2 > oxaphosphorin‐6‐yl)]naphthalene‐bis(trimellitate) dianhydride with a mixture of an aromatic diamine (1,3‐bis(4‐aminophenoxy)benzene) and α,ω‐bis(3‐aminopropyl)oligodimethylsiloxane of controlled molecular weight, in various ratios. Poly(amic acid) intermediates were converted quantitatively to the corresponding polyimide structures using a solution imidization procedure. The polymers are easily soluble in polar organic solvents, such as N‐methyl‐2‐pyrrolidone and N,N‐dimethylformamide, as well as in less polar solvents such as tetrahydrofuran. They show good thermal stability, the decomposition temperature being above 370 °C. The glass transition temperatures are in the range 165–216 °C. Solutions of the polymers in N‐methyl‐2‐pyrrolidone exhibit photoluminescence in the blue region. Copyright © 2010 Society of Chemical Industry     

Fluorene‐based conjugated polymer with tethered thymines: click postpolymerization synthesis and optical response to mercury(II)

A kind of fluorene‐based conjugated polymer with tethered thymine (T) groups {poly[(9,9‐dioctyl)‐2,7‐fluorene‐{9,9‐dioctyl‐4–1,2,3‐triazol‐[5‐(hydroxymethyl)tetrahydrofuran‐2‐yl]‐5‐methylpyrimidine‐2,4(1H,3H)‐dione}‐2,7‐fluorene]‐co‐[(9,9‐dioctyl)‐2,7‐fluorene‐4,7‐bis(5‐thiophen‐2‐yl)benzo‐2,1,3‐thiadiazole] ( P‐3 )} was successfully synthesized by a Cu(I)‐catalyzed click reaction between the acetylene‐substituted polymer precursor {poly[(9,9‐dioctyl)‐2,7‐fluorene‐(9,9‐dioctyl‐4‐phenylacetylene fluorene)]‐co‐[(9,9‐dioctyl)‐2,7‐fluorene‐4,7‐bis(5‐thiophen‐2‐yl)benzo‐2,1,3‐thiadiazole]} and 3′‐azido‐3′‐deoxythymidine. The chemical structures of the intermediates and target polymer were verified by Fourier transform infrared spectroscopy and ¹H‐NMR analyses. The specific binding with Hg²⁺ of P‐3 was corroborated by ultraviolet–visible spectroscopy and photoluminescence analyses against other metal ions. The results show that P‐3 possessed selectivity and sensitivity toward Hg²⁺. Around 77% of photoluminescence intensity of P‐3 was quenched when the concentration of Hg²⁺ reached 7.7 × 10^?4 M and with a detection limit in the range of about 4.8 μM. A comparison experiment suggested that a synergic effect of the tethered T and S atoms interrelated with Hg²⁺ existed in P‐3 . Most of the fluorescence intensity of P‐3 was recovered upon the addition of iodide anions to the P‐3 /Hg²⁺ complex; this suggested that P‐3 could be used as a potential reversible optical Hg²⁺ probe. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Poly(N‐[4H‐1,2,4‐triazol‐4‐yl]acrylamide) with different ratio of poly(vinyl chloride) composite membrane for liquid phase sensing of alcohol

Functionalized polymer membranes have been used as sensor materials for fabrication of electronic tongue. Here, we report the synthesis and characterization of a novel poly(N‐[4H‐1,2,4‐triazol‐4‐yl]acrylamide) (PNTA) for liquid phase aliphatic alcohol sensing in the form of membranes prepared after blending with poly(vinyl chloride) (PVC). Three PNTA‐PVC based membranes were prepared for sensing of six aliphatic alcohols. Polymer membranes were characterized by spectroscopic techniques. Polar groups on PNTA molecules contribute to the alcohol sensing characteristics. The membrane electric potential, generated by the interaction between membrane surface and aqueous aliphatic alcohols, was monitored with the developed multi‐channel electrode based prototype sensing system (MEBPSS). The polymer membranes showed distinct and repeatable response patterns toward different aliphatic alcohols. Among them PNTA‐PVC12 membrane showed maximum discrimination ability due to the PNTA molecules on the membrane surface with highest charge density as ascertained from field emission scanning electron microscopic studies. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44675.     

Direct (hetero)arylation polymerization for the synthesis of donor–acceptor conjugated polymers based on N‐benzoyldithieno [3,2‐b:2′,3′‐d]pyrrole and diketopyrrolopyrrole toward organic photovoltaic cell application

In this research, new donor–acceptor (D‐A) photovoltaic polymers were synthesized from dithieno[3,2‐b:2′,3′‐d]pyrrole electron donor derivatives, including N‐benzoyldithieno[3,2‐b:2′,3′‐d]pyrrole and N‐(4‐hexylbenzoyl)dithieno[3,2‐b:2′,3′‐d]pyrrole, in combination with the electron deficient unit 2,5‐bis(2‐ethylhexyl)‐3,6‐di(thiophen‐2‐yl)‐2,5‐dihydropyrrolo[3,4‐c]pyrrole‐1,4‐dione via direct (hetero)arylation polymerization. The D‐A conjugated polymers obtained were characterized via ¹H NMR, gel permeation chromatography, Fourier transform infrared spectroscopy, DSC, XRD, photoluminescence and UV–visible methods. In addition, these D‐A polymers were used as activated layers in bilayer and bulk heterojunction structures for the fabrication of organic photovoltaic cells. © 2019 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.