Molecular Recognition of Imidazole-Based Drug Molecules by Cobalt(III)- and Zinc(II)-Coproporphyrins in Aqueous Media

The methods of ¹H NMR, spectrophotometric titration, mass spectrometry and elemental analysis are applied to determine the selective binding ability of Co(III)- and Zn(II)-coproporphyrins I towards a series of imidazole-based drug molecules with a wide spectrum of pharmacological activity (metronidazole, histamine, histidine, tinidazole, mercazolil, and pilocarpine) in phosphate buffer (pH 7.4) simulating the blood plasma environment. It is shown that in aqueous buffer media, Co(III)-coproporphyrin I, unlike Zn(II)-coproporphyrin I, binds two imidazole derivatives, and the stability of mono-axial Co-coproporphyrin imidazole complexes is two to three orders of magnitude higher than that of similar complexes of Zn-coproporphyrin I. The studied porphyrinates are found to have the highest binding ability to histamine and histidine due to the formation of two additional hydrogen bonds between the carboxyl groups of the porphyrinate side chains and the binding sites of the ligands in the case of histidine and a hydrogen bond between the amino group of the ligand and the carbonyl oxygen atom of the carboxyl group of the porphyrinate in the case of histamine. The structures of the resulting complexes are optimized by DFT quantum chemical calculations. The results of these studies may be of use in the design of biosensors, including those for the detection, control and verification of various veterinary drug residues in human food samples.

Nanoparticles of N-Vinylpyrrolidone Amphiphilic Copolymers and Pheophorbide a as Promising Photosensitizers for Photodynamic Therapy: Design, Properties and In Vitro Phototoxic Activity

A series of nanoparticles (NPs) with a hydrodynamic radius from 20 to 100 nm in PBS was developed over the solubilization of hydrophobic dye methyl pheophorbide a (chlorin e₆ derivative) by amphiphilic copolymers of N-vinylpyrrolidone with (di)methacrylates. Photophysical properties and biological activity of the NPs aqueous solution were studied. It was found that the dye encapsulated in the copolymers is in an aggregated state. However, its aggregation degree decreases sharply, and singlet oxygen quantum yield and the fluorescence signal increase upon the interaction of these NPs with model biological membranes-liposomes or components of a tissue homogenate. The phototoxic effect of NPs in HeLa cells exceeds by 1.5-2 times that of the reference dye chlorin e₆ trisodium salt-one of the most effective photosensitizers used in clinical practice. It could be explained by the effective release of the hydrophobic photosensitizer from the NPs into biological structures. The demonstrated approach can be used not only for the encapsulation of hydrophobic photosensitizers for PDT but also for other drugs, and N-vinylpyrrolidone amphiphilic copolymers show promising potential as a modern platform for the design of targeted delivery vehicles.

Aryl- and Superaryl-Extended Calix[4]pyrroles: From Syntheses to Potential Applications

The incorporation of aryl substituents at the meso-positions of calix[4]pyrrole (C4P) scaffolds produces aryl-extended (AE) and super-aryl-extended (SAE) calix[4]pyrroles. The cone conformation of the all-α isomers of "multi-wall" AE-C4Ps and SAE-C4Ps displays deep aromatic clefts or cavities. In particular, "four-wall" receptors feature an aromatic polar cavity closed at one end with four convergent pyrrole rings and fully open at the opposite end. This makes AE- and SAE-C4P scaffolds effective receptors for the molecular recognition of negatively charged ions and neutral guest molecules with donor-acceptor and hydrogen bonding motifs. In addition, adequately functionalized all-α isomers of multi wall AE- and SAE-C4P scaffolds self-assemble into uni-molecular and supra-molecular aggregates displaying capsular and cage-like structures. The self-assembly process requires the presence of template ions or molecules that lock the C4P cone conformation and complementing the inner polar functions and volumes of their cavities. We envisioned performing an in-depth revision of AE- and SAE-C4P scaffolds owing to their importance in different domains such as supramolecular chemistry, biology, material sciences and pharmaceutical chemistry. Herewith, besides the synthetic details on the elaboration of their structures, we also draw attention to their diverse applications. The organization of this review is mainly based on the number of "walls" present in the AE-C4P derivatives and their structural modifications. The sections are further divided based on the C4P functions and applications. The authors are convinced that this review will be of interest to researchers working in the general area of supramolecular chemistry as well as those involved in the study of the binding properties and applications of C4P derivatives.

Acoplanarity, Aromaticity, Chirality, and Helical Twisting Power of Chlorin e6 13(N)-Methylamide-15,17-dimethyl Ester Complexes: Effect of a Metal

The experimental and theoretical study of the influence of metal complexing on geometry, aromaticity, chirality, and the ability to twist the nematic phase by complexes based on modified natural chlorin e6 was carried out. The geometry optimization of the chlorin e6 13(N)-methylamide-15,17-dimethyl ester (MADMECl) and its Zn, Cu, and Ni complexes by DFT (CAM-B3LYP/6–31 G(d,p) functional) method was performed. Based on these calculations, the acoplanarity degree of the macrocyclic ligand and the distortion energy of its dianion were estimated, which allowed the arrangement of the MADMECl complexes in the series Ni > Cu > Zn. Aromaticity was evaluated using the NICS criterion (nuclear independent chemical shift). An increase in the degree of aromaticity of the macrocycle upon complex formation was established. At the same time, the aromaticity of the inner conjugation contour corresponds to the same series as the acoplanarity, while the outer π-delocalization is characterized by the reverse sequence. An experimental evaluation of the electron circular dichroism of the Soret and the Q-bands, as well as the g-factor of dissymmetry, was carried out. The growth of these parameters with an increase in the degree of acoplanarity and aromaticity of the internal conjugation contour was determined. The induction of helical phases in mixtures of nematic liquid crystals (LCs) based on cyanobiphenyls and MADMECl macrocyclic metal complexes was studied by polarization microscopy, and the clearance temperatures and helix pitch of the mesophases were measured. A strong effect of the metal on the phase transition temperature and helical twisting power was established.

Complexation ability of tetrasulfosubstituted cobalt(II) phthalocyanine toward ORF3a protein of SARS-CoV-2 virus

Complex formation processes of tetrasulfosubstituted cobalt(II) phthalocyanine with ORF3a accessory protein of SARS-CoV-2 coronavirus were studied. The interaction of ORF3a protein with SARS-CoV-2 virus with tetrasulfosubstituted cobalt(II) phthalocyanine affords a stable complex in which metallophthalocyanine exists in the monomeric form. The complex formation induces slight changes in the secondary structure of the protein by increasing the fraction of disordered fragments of the polypeptide chain. The photoirradiation of the complex of ORF3a protein of SARS-CoV-2 virus with tetrasulfosubstituted cobalt(II) phthalocyanine leads to the photooxidation of amino acid residues of the protein.

Synthesis of water-soluble porphyrin with tyrosine fragments and study of its interaction with S-protein of SARS-CoV-2

The multistage purposeful synthesis of 5,15-bis(4'-l-N-tyrosinylamidophenyl)-10,20-bis(N-methylpyridin-3'-yl)porphine diiodide was carried out, and the optimum synthesis conditions were determined. 5,15-Bis(4'-nitrophenyl)-10,20-bis(pyridin-3'-yl)porphine served as the starting porphyrin. The structure, individual character, and purity of the target compound were proved by electron spectroscopy, 1H NMR spectroscopy, mass spectrometry (MALDI TOF), and TLC. Specific features of the interaction of the synthesized porphyrin with S-protein of SARS-CoV-2 were studied using spectral and thermochemical methods, including conditions of photoirradiation. The photoirradiation of the synthesized porphyrin in a complex with the SARS-CoV-2 S-protein can result in the partial oxidation of amino acid residues of the protein and distort its primary and secondary structures. The photoirradiation of the S-protein complex with the porphyrin decreases its thermal resistance to melting by 15 °C compared to the free S-protein and causes porphyrin release.

Synthesis, Structure, and Spectral-Luminescent Properties of Peripherally Fluorinated Mg(II) and Zn(II) Octaphenyltetraazaporphyrins

The cyclization of di-(2,6-difluorophenyl)maleindinitrile with magnesium(II) and zinc(II) acetates in boiling ethylene glycol is applied to synthesize Mg(II) and Zn(II) complexes of the octa-(2,6-difluorophenyl)tetraazaporphyrin. The compounds are identified by UV-Vis, ¹H NMR, and mass spectrometry methods. A comparative analysis is performed of the spectral-luminescent properties of magnesium and zinc octaaryltetraazaporphyrinates and their dependence on the number and position of the fluorine atoms in the macrocycle phenyl fragments. The DFT method is used to optimize the geometry of the synthesized complexes. Machine learning methods and QSPR are applied to predict the Soret band wavelength in the UV-V is spectra of the complexes described.

Switchable Nanozyme Activity of Porphyrins Intercalated in Layered Gadolinium Hydroxide

In this study, organo-inorganic nanohybrids LHGd-MTSPP with enzyme-like activity were prepared by in situ intercalation of anionic 5,10,15,20-tetrakis-(4-sulfonatophenyl)porphyrin and its complexes with Zn(II) and Pd(II) (MTSPP, M = 2H, Zn(II) and Pd(II)) into gadolinium layered hydroxide (LHGd). The combination of powder XRD, CHNS analysis, FT-IR, EDX, and TG confirmed the layered structure of the reaction products. The basal interplanar distances in LHGd-MTSPP samples were 22.3-22.6 Å, corresponding to the size of an intercalated tetrapyrrole molecule. According to SEM data, LHGd-MTSPP hybrids consisted of individual lamellar nanoparticles 20-50 nm in thickness. The enzyme-like activity of individual constituents, LHGd-Cl and sulfoporphyrins TSPP, ZnTSPP and PdTSPP, and hybrid LHGd-MTSPP materials, was studied by chemiluminescence analysis using the ABAP/luminol system in phosphate buffer solution. All the individual porphyrins exhibited dose-dependent antioxidant properties with respect to alkylperoxyl radicals at pH 7.4. The intercalation of free base TSPP porphyrin into the LHGd preserved the radical scavenging properties of the product. Conversely, in LHGd-MTSPP samples containing Zn(II) and Pd(II) complexes, the antioxidant properties of the porphyrins changed to dose-dependent prooxidant activity. Thus, an efficient approach to the design and synthesis of advanced LHGd-MTSPP materials with switchable enzyme-like activity was developed.

Complexation of Oligo- and Polynucleotides with Methoxyphenyl-Functionalized Imidazolium Surfactants

Interaction between cationic surfactants and nucleic acids attracts much attention due to the possibility of using such systems for gene delivery. Herein, the lipoplexes based on cationic surfactants with imidazolium head group bearing methoxyphenyl fragment (MPI-n, n = 10, 12, 14, 16) and nucleic acids (oligonucleotide and plasmid DNA) were explored. The complex formation was confirmed by dynamic/electrophoretic light scattering, transmission electron microscopy, fluorescence spectroscopy, circular dichroism, and gel electrophoresis. The nanosized lipoplex formation (of about 100-200 nm), contributed by electrostatic, hydrophobic interactions, and intercalation mechanism, has been shown. Significant effects of the hydrocarbon tail length of surfactant and the type of nucleic acid on their interaction was revealed. The cytotoxic effect and transfection ability of lipoplexes studied were determined using M-HeLa, A549 cancer cell lines, and normal Chang liver cells. A selective reduced cytotoxic effect of the complexes on M-HeLa cancer cells was established, as well as a high ability of the systems to be transfected into cancer cells. MPI-n/DNA complexes showed a pronounced transfection activity equal to the commercial preparation Lipofectamine 3000. Thus, it has been shown that MPI-n surfactants are effective agents for nucleic acid condensation and can be considered as potential non-viral vectors for gene delivery.

Structure Determination of Binuclear Triple-Decker Phthalocyaninato Complexes by NMR via Paramagnetic Shifts Analysis Using Symmetry Peculiarities

The detailed knowledge about the structure of multinuclear paramagnetic lanthanide complexes for the targeted design of these compounds with special magnetic, sensory, optical and electronic properties is a very important task. At the same time, establishing the structure of such multinuclear paramagnetic lanthanide complexes in solution, using NMR is a difficult task, since several paramagnetic centers act simultaneously on the resulting chemical shift of a particular nucleus. In this paper, we have demonstrated the possibility of molecular structure determination in solution on the example of binuclear triple-decker lanthanide(III) complexes with tetra-15-crown-5-phthalocyanine Ln₂[(15C5)₄Pc]₃ {where Ln = Tb (1) and Dy (2)} by quantitative analysis of the pseudo-contact lanthanide-induced shifts (LIS). The symmetry of complexes was used for the simplification of the calculation of pseudo-contact shifts on the base of the expression for the magnetic susceptibility tensor in the arbitrary oriented magnetic axis system. Good agreement between the calculated and experimental shifts in the ¹H NMR spectra indicates the similarity of the structure for the complexes 1 and 2 in solution of CDCl₃ and the structure in the crystalline phase, found from the data of the X-ray structural study of the similar complex Lu₂[(15C5)₄Pc]₃. The described approach can be useful for LIS analysis of other polynuclear symmetric lanthanide complexes.

The Role of Hidden Conformers in Determination of Conformational Preferences of Mefenamic Acid by NOESY Spectroscopy

Mefenamic acid has been used as a non-steroidal anti-inflammatory drug for a long time. However, its practical use is quite limited due to a number of side effects on the intestinal organs. Conformational polymorphism provides mefenamic acid with unique properties regarding possible modifications obtained during the micronization process, which can improve pharmacokinetics and minimize side effects. Micronization can be performed by decompression of supercritical fluids; methods such as rapid expansion of the supercritical solution have proven their efficiency. However, this group of methods is poorly applicable for compounds with low solubility, and the modification of the method using a pharmaceutically suitable co-solvent may be useful. In our case, addition of only 2 mol% dimethyl sulfoxide increased the solubility remarkably. Information on the conformational state may be critically important for carrying out micronization. In this work, structural analysis and estimate of conformational preferences of mefenamic acid in dimethyl sulfoxide-d6 (at 25 °C and 0.1 MPa) and in a mixed solvent supercritical carbon dioxide + dimethyl sulfoxide-d6 (45 °C, 9 MPa) were performed based on nuclear Overhauser effect spectroscopy. Results show changes in the conformation fractions depending on the medium used. The importance of allowing for hidden conformers in estimating the conformational state was demonstrated in the analysis. Obtained results may be useful for improving micronization parameters.

Can machine learning methods accurately predict the molar absorption coefficient of different classes of dyes?

In this article, we provide a convenient tool for all researchers to predict the value of the molar absorption coefficient for a wide number of dyes without any computer costs. The new model is based on RFR method (ALogPS, OEstate + Fragmentor + QNPR) and is able to predict the molar absorption coefficient with an accuracy (5-fold cross-validation RMSE) of 0.26 log unit. This accuracy was achieved due to the fact that the model was trained on data for more than 20,000 unique dye molecules. To our knowledge, this is the first model for predicting the molar absorption coefficient trained on such a large and diverse set of dyes. The model is available at https://ochem.eu/article/145413. We hope that the new model will allow researchers to predict dyes with practically significant spectral characteristics and verify existing experimental data.

Aggregation behavior and spectroscopic properties of red-emitting distyryl-BODIPY in aqueous solution, Langmuir-Schaefer films and Pluoronic® F127 micelles

Red-emitting distyryl substituted BODIPY dyes are among the most promising luminophors for bioimaging and optics applications. However, the practical application of BODIPYs is limited due to their high hydrophobicity and tendency to aggregate in aqueous organic solutions and solid phase. In this article, we propose an elegant solution to this problem. To this end, we carried out the detailed experimental and quantum-chemical study of the structural and spectral features of BF₂-ms-phenyl-5,5'-bis(4-dimethylaminostyryl)-3,3'-dimethyl-2,2'-dipyrromethene (distyryl-BDP). The particular attention was paid to analysis of high sensitivity of the distyryl-BDP spectral characteristics to the solvent properties, and also the aggregation behavior features both in water-organic media and in mono- and multilayer Langmuir-Schaefer films. We selected the best conditions to obtain the hydrophilic micellar structures of distyryl-BDP with Pluronic® F127 having a high efficiency of dye solubilization. This method increasing the solubility improves the distyryl-BDP transport efficiency in physiological aqueous media. The aqueous solutions of distyryl-BDP-Pl micelles show the intense fluorescence in the phototherapy window region (λ_fl = 739 nm).

Novel porphyrazine derivative – 2,3,5,7,8,10,12,13,15,17,18,20-dodecaazaporphin and its complexes with M(II) ions of 3d-elements: DFT quantum-chemical modeling

Using three different versions of the density functional theory (DFT) – B3PW91/TZVP, M06/TZVP and OPBE/TZVP chemical models, the calculation of the molecular structures of (6666) macrocyclic complexes of 3d-elements (M) with a novel (NNNN)-donor macrocyclic ligand, 2,3,5,7,8,10,12,13,15,17,18,20-dodecaazaporphin (H2L), was carried out. The values of the most important bond lengths, bond and non-bond angles in these metal complexes were presented. The standard enthalpy, entropy, and Gibbs energy of formation of these compounds were also calculated. It was noted that according to the data of the above chemical models, [MnL], [FeL], [CoL], [NiL], and [CuL] complexes with this novel ligand have a flat MN4 chelate node and a planar structure as a whole, while the [TiL], [VL], [CrL] and [ZnL] complexes have a non-coplanar MN4 chelate node. Moreover, all 6-membered rings in each of these metal chelates are identical to each other (both in terms of the sum of the bond angles included in them and in their assortment); adjoining 5-membered cycles for the majority of M are also identical to each other (non-identity is noted only in the cases M = Ti, Mn, as well as for the original 2,3,5,7,8,10,12,13,15,17,18,20-dodecaazaporphin). A good agreement was also noted between similar parameters calculated by various DFT methods, both qualitatively and quantitatively.

Redox-Triggered Switching of Conformational State in Triple-Decker Lanthanide Phthalocyaninates

Double- and triple-decker lanthanide phthalocyaninates exhibit unique physical-chemical properties, particularly single-molecule magnetism. Among other factors, the magnetic properties of these sandwiches depend on their conformational state, which is determined via the skew angle of the phthalocyanine ligands. Thus, in the present work we report the comprehensive conformational study of substituted terbium(III) and yttrium(III) trisphthalocyaninates in solution depending on the substituents at the periphery of molecules, redox-states and nature of solvents. Conjunction of UV-vis-NIR spectroscopy and quantum-chemical calculations within simplified time-dependent DFT in Tamm-Dancoff approximation provided the spectroscopic signatures of staggered and gauche conformations of trisphthalocyaninates. Altogether, it allowed us to demonstrate that the butoxy-substituted complex behaves as a molecular switcher with controllable conformational state, while the crown-substituted triple-decker complex maintains a staggered conformation regardless of external factors. The analysis of noncovalent interactions within the reduced density gradient approach allowed to shed light on the nature of factors stabilizing certain conformers.

Oxidative Cyclodehydrogenation of Trinaphthylamine: Selective Formation of a Nitrogen-Centered Polycyclic π-System Comprising 5- and 7-Membered Rings

We describe a new type of nitrogen-centered polycyclic scaffold comprising a unique combination of 5-, 6-, and 7-membered rings. The compound is accessible through an intramolecular oxidative cyclodehydrogenation of tri(1-naphthyl)amine. To the best of our knowledge this is the very first example of a direct 3-fold cyclization of a triarylamine under oxidative conditions. The unusual ring fusion motif is confirmed by X-ray crystallography and the impact of cyclization on the electronic and photophysical properties is investigated both experimentally and theoretically based on density-functional theory (DFT) calculations. The formation of the unexpected product is rationalized by detailed mechanistic studies on the DFT level. The results suggest the cyclization to occur under kinetic control via a dicationic mechanism.

Controlled Self-Assembly of Low-Dimensional Supramolecular Systems Based on Double-Decker Lanthanide Phthalocyaninates

Abstract

Possessing unique physicochemical properties, phthalocyanines are widely used as active components of supramolecular ensembles and nanomaterials. The functional properties of phthalocyanine-based materials are governed by not only the structure of their discotic molecules, but also the character of their intermolecular interactions, which determine both the self-assembly mechanism and the structure of such systems. This review discusses the experimental approaches, which are based on the notions of colloid and coordination chemistry that enable one to control intermolecular interactions in low-dimensional supramolecular ensembles based on phthalocyanines and metallocomplexes thereof. Using double-decker crown-substituted lanthanide phthalocyaninates as an example, it is shown how one- and two-dimensional nanomaterials with different properties can be obtained from the same type of building blocks employing a set of colloid-chemical methods. Such materials are, in particular, capable for controlled absorption of visible light in ultrathin films and can be employed as conducting one-dimensional components of planar elements for organic electronics.

Design, Synthesis, Electronic Properties, and X-ray Structural Characterization of Various Modified Electron-Rich Calixarene Derivatives and Their Conversion to Stable Cation Radical Salts

We have designed and synthesized electron-rich calixarene derivatives, which undergo reversible electrochemical oxidation in a well-accessible potential range that allows the ready preparation and isolation of the corresponding cation radicals. Preparation of mono- or tetra-radical cation can be achieved by using stable aromatic cation-radical salts such as MA+•, MB+•, and NAP+• as selective organic oxidants. The cation radicals of calixarenes are stable indefinitely at ambient temperatures and can be readily characterized by UV-vis-NIR spectroscopy. These cation radicals bind a single molecule of nitric oxide within its cavity with remarkable efficiency.

Aromatic heterobicycle-fused porphyrins: impact on aromaticity and excited state electron transfer leading to long-lived charge separation

A new synthetic method to fuse benzo[4,5]imidazo[2,1-a]isoindole to the porphyrin periphery at the β,β-positions has been developed, and its impact on the aromaticity and electronic structures is investigated. Reactivity investigation of the fused benzoimidazo-isoindole component reveals fluorescence quenching of a zinc porphyrin (AMIm-2) upon treatment with a Brønsted acid. The reaction of the zinc porphyrin (AMIm-2) with methyl iodide initiated a new organic transformation, resulting in the ring-opening of isoindole with the formation of an aldehyde and dimethylation of the benzoimidazo component. The fused benzoimidazo-isoindole component acted as a good ligand to bind platinum(ii), forming novel homobimetallic and heterobimetallic porphyrin complexes. The fusion of benzoimidazo-isoindole on the porphyrin ring resulted in bathochromically shifted absorptions and emissions, reflecting the extended conjugation of the porphyrin π-system. Time-resolved emission and transient absorption spectroscopy revealed stable excited state species of the benzoimidazo-isoindole fused porphyrins. Zinc porphyrin AMIm-2 promoted excited state electron transfer upon coordinating with an electron acceptor, C60, generating a long-lived charge-separated state, in the order of 37.4 μs. The formation of the exceptionally long-lived charge-separated state is attributed to the involvement of both singlet and triplet excited states of AMIm-2, which is rarely reported in porphyrins.

Nonplanar porphyrins: synthesis, properties, and unique functionalities

Porphyrins are variously substituted tetrapyrrolic macrocycles, with wide-ranging biological and chemical applications derived from metal chelation in the core and the 18π aromatic surface. Under suitable conditions, the porphyrin framework can deform significantly from regular planar shape, owing to steric overload on the porphyrin periphery or steric repulsion in the core, among other structure modulation strategies. Adopting this nonplanar porphyrin architecture allows guest molecules to interact directly with an exposed core, with guest-responsive and photoactive electronic states of the porphyrin allowing energy, information, atom and electron transfer within and between these species. This functionality can be incorporated and tuned by decoration of functional groups and electronic modifications, with individual deformation profiles adapted to specific key sensing and catalysis applications. Nonplanar porphyrins are assisting breakthroughs in molecular recognition, organo- and photoredox catalysis; simultaneously bio-inspired and distinctly synthetic, these molecules offer a new dimension in shape-responsive host-guest chemistry. In this review, we have summarized the synthetic methods and design aspects of nonplanar porphyrin formation, key properties, structure and functionality of the nonplanar aromatic framework, and the scope and utility of this emerging class towards outstanding scientific, industrial and environmental issues.

Synthesis of Metalorganic Copolymers Containing Various Contorted Units and Iron(II) Clathrochelates with Lateral Butyl Chains: Conspicuous Adsorbents of Lithium Ions and Methylene Blue

We report the synthesis of three highly soluble metalorganic copolymers, TCP1-3, that were made from a one-pot complexation of iron(II) clathrochelate units that are interconnected by various thioether-containing contorted groups. TCP1-3 were converted into their poly(vinyl sulfone) derivatives OTCP1-3 quantitatively via the selective oxidation of the thioether moieties into their respective sulfones. All of the copolymers, TCP1-3 and OTCP1-3, underwent structural analysis by various techniques; namely, ¹H- and ¹³C-nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and gel permeation chromatography (GPC). The copolymers were tested as potent lithium ions adsorbents revealing a maximum adsorption (q_m) value of 2.31 mg g^-1 for OTCP2. Furthermore, this same copolymer was found to be a promising adsorbent of methylene blue (MEB); an isothermal adsorption study divulged that OTCP2's uptake of MEB from an aqueous solution (following the Langmuir model) was, at maximum adsorption capacity, (q_m) of 480.77 mg g^-1; whereas the kinetic study divulged that the adsorption follows pseudo second-order kinetics with an equilibrium adsorption capacity (q_e,cal) of 45.40 mg g^-1.