Imidazole Fragment Research Articles

Mutual influence of non-covalent interactions formed by imidazole: A systematic quantum-chemical study.

Imidazole is a five-membered heterocycle that is part of a number of biologically important molecules such as the amino acid histidine and the hormone histamine. Imidazole has a unique ability to participate in a variety of non-covalent interactions involving the NH group, the pyridine-like nitrogen atom or the π-system. For many biologically active compounds containing the imidazole moiety, its participation in formation of hydrogen bond NH⋯O/N and following proton transfer is the key step of mechanism of their action. In this work a systematic study of the mutual influence of various paired combinations of non-covalent interactions (e.g., hydrogen bonds and π-interactions) involving the imidazole moiety was performed by means of quantum chemistry (PW6B95-GD3/def2-QZVPD) for a series of model systems constructed based on analysis of available x-ray data. It is shown that for considered complexes formation of additional non-covalent interactions can only enhance the proton-donating ability of imidazole. At the same time, its proton-accepting ability can be both enhanced and weakened, depending on what additional interactions are added to a given system. The mutual influence of non-covalent interactions involving imidazole can be classified as weak geometric and strong energetic cooperativity-a small change in the length of non-covalent interaction formed by imidazole can strongly influence its strength. The latter can be used to develop methods for controlling the rate and selectivity of chemical reactions involving the imidazole fragment in larger systems. It is shown that the strong mutual influence of non-covalent interactions involving imidazole is due to the unique ability of the imidazole ring to effectively redistribute electron density in non-covalently bound systems with its participation.

ТЕРМОДИНАМИКА КОМПЛЕКСООБРАЗОВАНИЯ И СТРУКТУРА КОМПЛЕКСОВ ЦИНКА(II) С ГИСТИДИНОМ И 2-МЕТИЛДИПИРИДОХИНОКСАЛИНОМ

The complex formation in the zinc(II) - 2-methyldipyrido-[3,2-f:2',3'-h]-quinoxaline (MeDPQ), zinc(II) - L-histidine (HisH) and zinc(II) - 2-methyldipyrido-[3,2-f:2',3'-h]-quinoxaline - L-histidine systems at 37.0 °C on the 0.15 mol dm-3 NaCl background has been investigated by the pH-potentiometry method. A total of 10 complex forms were characterized. Based on the analysis of the complex formation constants and DFT calculations at the B3LYP/TZVPP level, taking into account the solvent effect within the C-PCM model, the structures of Zn(MeDPQ)(HisH)2+, Zn(MeDPQ)(His)+, and Zn(MeDPQ)(His)(OH) complexes were modeled. The higher stability of the homoligand complexes Zn(His)+, Zn(HisH)(His)+, Zn(His)2 and extra-stabilization in the formation constants of the heteroligand complexes Zn(MeDPQ)(HisH)2+ and Zn(MeDPQ)(His)+ were discovered, which was confirmed by the DFT calculations. Higher values of equilibrium constants of the mentioned homoligand forms are explained by coordination to the central nitrogen atom of the imidazole fragment of histidine. Extra-stabilization of heteroligand forms occurs due to d-π-interaction with electron density transfer from π-donor orbitals of oxygen atoms of the carboxy groups of amino acids through the central ion to π-acceptor orbitals of MeDPQ. It is emphasized that the studied zinc(II) complexes, both in binary and ternary systems, can have high biological activity, in particular, due to the nucleophilic attack of the coordinated hydroxide anion on proteins and other biomaterials. This opens up the prospect of using such zinc(II) complexes in medicine. In particular, the studied complexes may exhibit anticancer activity.

Heterogeneous Phosphine-Containing Hydroformylation Catalysts Based on Modified Porous Organic Framework

A series of heterogeneous phosphine-containing rhodium hydroformylation catalysts based on porous aromatic frameworks (PAFs) were prepared. The catalysts PAF30-MDEA-TPPTS-Rh (TPPTS is trisodium triphenylphosphine-3,3',3''-trisulfonate, MDEA is methyldiethanolamine fragment) and PAF-30-Im-TPPTS-Rh (Im is imidazole fragment) showed the highest stability in repeated use in 1-hexene hydroformylation. The catalyst PAF-30-MDEA-TPPTS-Rh before and after use in hydroformylation was characterized by elemental C,N,H,S analysis, inductively coupled plasma atomic absorption spectroscopy, low-temperature nitrogen adsorption–desorption, transmission electron microscopy, IR spectroscopy, and X-ray photoelectron spectroscopy. The effect of temperature, pressure, and solvent on the course of hydroformylation in the presence of PAF-30-MDEA-TPPTS-Rh was studied. The catalyst is active in hydroformylation of a series of unsaturated compounds, including functionalized substrates and olefins with internal double bond.

Special Features of Multiple Luminescence of the Dyad Containing Imidazole and Coumarin Fragments in Photocured Network Acrylate Polymers

The conditions to prepare luminescent acrylate polymers containing the organic dyad, molecule of which combines two different emitting fragments, hydroxyl-substituted 2,4,5–triarylimidazole and 8-azomethine-7-hydroxycoumarine moieties, via photocuring have been optimized. The effect of the nature of the photocured network acrylate polymers on luminescent properties of the dyad has been investigated. The prepared aliphatic network polymers have exhibited independent fluorescence of both molecule fragments, dependent on the excitation wavelength. At the same time, the aromatic network polymers and the aliphatic network polymers containing ether links have revealed only the imidazole fragment fluorescence. The fluorescence nature has been stronger dependent on the polymer repeat unit structure and the content of the aromatic fragments in the polymer matrix than on the presence of the hydroxyl groups in the polymer. It has been shown that the emission of the imidazole fragment of the dyad in the aliphatic network polymers depends on the internode distance and conditional polarity of the medium.

POTENTIAL OF IMIDAZOLE-CONTAINING DERIVATIVES FOR PRACTICAL APPLICATION (Review)

The imidazole ring is becoming a popular structural fragment in synthetic pharmaceuticals, being an ionizing and aromatic component, which activates pharmacokinetic properties. The imidazole cycle is present in many antiprototic, antifungal and antihypertensive drugs, antibiotics and others. These structures are effective against various strains of microorganisms. The imidazole block is contained in the anticancer drug mercaptopurine, which has an effect by interfering with the DNA activity in the treatment of leukemia. Purpose: to review imidazole derivatives with various types of physiological and/or other actions published in the scientific literature over the last twenty years. Objects of research: imidazole derivatives. Results.An imidazole fragment is contained in a large number of natural products and clinically active drug molecules. Most of the publications relate to the study of the therapeutic possibilities of new structures of the class of imidazole derivatives for medical use. However, the potential of imidazole-containing molecules is not limited only to BAS, their other properties are interesting, in particular such one as corrosion inhibition. Conclusion: The introduction of a highly active imidazole fragment into an organic molecule stimulated the appearance of notable achievements in the field of chemotherapeutic and antibacterial agents. The active synthetic search for highly active imidazole compounds continues not only in the field of biologically active compounds, but also as the potential anticorrosiveand other agents.

Reactions of 1,4-NCCN-, 1,4-NNCN- and 1,5-NCCCN-binucleophiles with dicarboxylic acids cyclic anhydrides as a method of heterocyclic compounds synthesis (a review)

Critical analysis of published information related to the features of reaction of 1,4-NCCN-, 1,4-NNCN and 1,5-NCCCN-binucleophiles with cyclic anhydrides of dicarboxylic acids has been presented in the review. It has been shown that the reaction of named anhydrides with 1,4-NCCN-binucleophiles leads to the formation of the imidazole fragment that contains carboxyl-containing moiety. It has been shown that benzimidazole derivatives are among the most studied products of reaction between 1,4-NCCN- and cyclic anhydrides of dicarboxylic acids due to the high availability of initial compounds. The approaches to chemical modification of latter compounds have been discussed as well. It has been found out that 1,4-NNCN-binucleophiles used in reactions with cyclic anhydrides of dicarboxylic acids are mostly presented by amidines and amidrazones. The effects of structures of initial compounds and conditions of reactions on the products of reaction have been described. Literature data shows that the reaction of 1,5-NCCCN-binucleophiles such as amides and hydrazides of anthranilic acid, diamino-substituted polycyclic arenes and 2-azaheterylanilines with cyclic anhydrides of dicarboxylic acids commonly results in the formation of pyrimidine derivatives. It has been established that the application of cyclic anhydrides of non-symmetric dicarboxylic acid as reagents may cause the ambiguity of the reaction pathways. However, the formation of single products of interaction between binucleophiles and non-symmetric anhydrides can be achieved by variation of reaction conditions. The biological activity of the discussed reaction products has been considered in detail. It has been shown that the above-mentioned compounds reveal antibacterial, antifungal, anticancer, immunomodulate, and antidiabetic activities.

Structural correlations of complexation of apple pectin with imidazole and L-histidine methyl ester

The thermodynamic and structural study of the complex formation of apple pectin with structural analogs of histidine (imidazole and its methyl ester) was carried out using spectral methods. The composition, stability constants of the complexes, and standard thermodynamic characteristics (Δ G° , Δ H° , Δ S° ) of the complex formation process were determined. The decisive contribution of the imidazole fragment of the amino acid to the stability of the pectin-histidine complex is shown. The esterification of the carboxyl group of histidine, its conversion into methyl ester, has an insignificant effect on the efficiency of complex formation with pectin, leading only to a slight increase in binding.

Design, Synthesis and Bioactivity Evaluation of Novel 2-(pyrazol-4-yl)-1,3,4-oxadiazoles Containing an Imidazole Fragment as Antibacterial Agents.

Imidazole alkaloids, a common class of five-membered aromatic heterocyclic compounds, exist widely in plants, animals and marine organisms. Because of imidazole's extensive and excellent biological and pharmacological activities, it has always been a topic of major interest for researchers and has been widely used as an active moiety in search of bioactive molecules. To find more efficient antibacterial compounds, a series of novel imidazole-fragment-decorated 2-(pyrazol-4-yl)-1,3,4-oxadiazoles were designed and synthesized based on our previous works via the active substructure splicing principle, and their bioactivities were systematically evaluated both in vitro and in vivo. The bioassays showed that some of the target compounds displayed excellent in vitro antibacterial activity toward three virulent phytopathogenic bacteria, including Xanthomonas oryzae pv. oryzae (Xoo), Xanthomonas axonopodis pv. citri (Xac) and Pseudomonas syringae pv. actinidiae (Psa), affording the lowest EC50 values of 7.40 (7c), 5.44 (9a) and 12.85 (9a) μg/mL, respectively. Meanwhile, compound 7c possessed good in vivo protective and curative activities to manage rice bacterial leaf blight at 200 μg/mL, with control efficacies of 47.34% and 41.18%, respectively. Furthermore, compound 9a showed commendable in vivo protective and curative activities to manage kiwifruit bacterial canker at 200 μg/mL, with control efficacies of 46.05% and 32.89%, respectively, which were much better than those of the commercial bactericide TC (31.58% and 17.11%, respectively). In addition, the antibacterial mechanism suggested that these new types of title compounds could negatively impact the cell membranes of phytopathogenic bacteria cells and cause the leakage of the intracellular component, thereby leading to the killing of bacteria. All these findings confirm that novel 2-(pyrazol-4-yl)-1,3,4-oxadiazoles containing an imidazole fragment are promising lead compounds for discovering new bactericidal agents.

Interaction of Three-Pole ions of carnosine and anserine with an anionic micelle of SDS: Molecular dynamics simulations

Molecular dynamics simulations of the interaction of an anionic micelle of 64 SDS molecules with carnosine and anserine (a substituted analogue) in their three-pole cationic form were performed. The formation of hydrogen bonds between the peptides and the micelle has been established. The H-bond lengths range from 0.184 to 0.198 nm. The H-binding sites in the peptides are the protonated amino group and the NH group in the protonated imidazole fragment, and in the case of carnosine, the uncharged NH group in the OCNH peptide fragment. The binding sites in the micelle are the anionic oxygen atoms located closer to the micelle surface. The ethereal oxygen atoms that bind the sulfo group to the surfactant hydrophobic tail do not show noticeable activity in the formation of hydrogen bonds. The average numbers and the lifetimes of the peptide - SDS and peptide - water H-bonds were determined. The differences in the orientations of equally charged three-pole ions of carnosine and anserine relative to the anionic micelle were discussed. For carnosine associated with the micelle, the ψ-dihedral angle in the alanine residue appears in two discrete zones due to the COO– group rotation. The two zones correspond to two peptide conformers differing in the about-turn of the CH2NH3+ fragment on the micelle surface. The steric correspondence of the peptides and micelle controls the process of H-bonding between them and leads to significant differences in the orientation of equally charged ions of the peptides on an anionic micelle.

Synthesis of Diorganylphosphine Oxides Bearing Hetarylalkyl Moieties and Study of Their Antimicrobial Activities

AbstractTertiary phosphine oxides have been synthesized by the reaction of secondary phosphine oxides with diverse hetarylmethylchlorides (pyridines, imidazoles, pyrazole) in the superbasic systems CsF/NaOH/DMF/4 Å MS or NaOH/DMSO/4 Å MS at 23–25 °C. It is found that a tertiary phosphine oxide bearing the imidazole fragment possess the pronounced antimicrobial activity.

Synthesis and Antimicrobial, Antiplatelet, and Anticoagulant Activities of New Isatin Deivatives Containing a Hetero-Fused Imidazole Fragment

A series of isatin derivatives containing an adenine or theophylline fragment have been synthesized. The corresponding N′-[2-(trimethylammonio)acetyl] and N′-(2-pyridinioacetyl) hydrazones have been found to exhibit neither cytotoxicity nor hemotoxicity. Quaternary salts based on adenine derivatives of 5-methyl- and 5-ethylisatins showed the highest antiplatelet activity which exceeded the activity of acetylsalicylic acid by a factor of 1.5.

SYNTHESIS AND FUNCTIONALIZATION OF SOME PARA-R-PHENYLIMIDAZO[2,1-B][1,3,4]- THIADIAZOLE DERIVATIVES

The article describes the synthesis of new modifications of derivatives of 6-phenyl-, 6-piodophenyl- and 6-p-bromophenylimidazo[2,1-b][1,3,4]-thiadiazoles - N -((6-(4-iodophenyl)-2-R-imidazo[2,1-b][1,3,4]-thiadiazol-5-yl)methyl)-alkyl/ heterylamine based on the Mannich reaction, bromination 2((ethylsulfonyl)methyl)-6-phenylimidazo[2,1-b][1,3,4]-thiadiazole and the structure of the resulting compounds was established on the basis of IR spectroscopy. It was shown that the presence of substituents at the 2-nd position of the thiadiazole fragment and substituents at the 5th and 6th positions of the imidazole fragment of this heterocycle cause the appearance of a nonequivalent absorption band in the imidazo-thiadiazole fragment.

Metal-Organic Fragments with Adhesive Excipient and Their Utilization to Stabilize Multimetallic Electrocatalysts for High Activity and Robust Durability in Oxygen Evolution Reaction.

Multimetallic electrocatalysts have shown great potential to improve electrocatalytic performance, but their deteriorations in activity and durability are yet to be overcome. Here, metal‐organic fragments with adhesive excipient to realize high activity with good durability in oxygen evolution reaction (OER) are developed. First, a leaf‐like zeolitic–imidazolate framework (ZIF‐L) is synthesized. Then, ionized species in hydrogen plasma attack preferentially the organic linkers of ZIF‐L to derive cobalt–imidazole fragments (CIFs) as adhesive excipient, while they are designed to retain the coordinated cobalt nodes. Moreover, the vacant coordination sites at cobalt nodes and the unbound nitrogen at organic linkers induce high porosity and conductivity. The CIFs serve to stably impregnate trimetallic FeNiMo electrocatalysts (CIF:FeNiMo), and CIF:FeNiMo containing Fe contents of 22% and hexavalent Mo contents show to enable high activity with low overpotentials (203 mV at 10 mA cm−2 and 238 mV at 100 mA cm−2) in OER. The near O K‐edge extended X‐ray absorption fine structure proves further that high activity for OER originates from the partially filled eg orbitals. Additionally, CIF:FeNiMo exhibit good durability, as demonstrated by high activity retention during at least 45 days in OER.

Stereochemical aspects in the synthesis of novel N-(purin-6-yl)dipeptides as potential antimycobacterial agents.

The synthesis of purine conjugates with natural amino acids is one of the promising directions in search for novel therapeutic agents, including antimycobacterial agents. The purpose of this study was to synthesize N-(purin-6-yl)dipeptides containing the terminal fragment of (S)-glutamic acid. To obtain the target compounds, two synthetic routes were tested. The first of them is based on coupling of N-(purin-6-yl)-(S)-amino acids to dimethyl (S)-glutamate in the presence of carbodiimide coupling agent followed by the removal of ester groups. However, it turned out that this coupling process was accompanied by racemization of the chiral center of N-(purin-6-yl)-α-amino acids and in all cases led to mixtures of (S,S)- and (R,S)-diastereomers (6:4). Individual (S,S)-diastereomers were obtained using an alternative approach based on the nucleophilic substitution of chlorine in 6-chloropurine or 2-amino-6-chloropurine with corresponding dipeptides as nucleophiles. The enantiomeric purity of the target compounds was confirmed by chiral HPLC. To test the assumption that racemization of the chiral center of N-(purin-6-yl)-α-amino acids occurs with the participation of nitrogen atoms of the imidazole ring via the stage of formation of a chirally labile intermediate, we obtained such structural analogs of N-(purin-6-yl)-(S)-alanine as N-(9-benzylpurin-6-yl)-(S)-alanine and N-(7-deazapurin-6-yl)-(S)-alanine. It was found that coupling of these compounds to dimethyl (S)-glutamate was also accompanied by racemization. This indicates that the imidazole fragment does not play a crucial role in this process. When testing the antimycobacterial activity of some of the obtained compounds, conjugates with moderate activity against the laboratory Mycobacterium tuberculosis H37Rv strain (MIC 3.1–6.25 μg/mL) were identified.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00726-021-02958-0.

СИНТЕЗ И ИЗУЧЕНИЕ СТРУКТУРЫ ТИОЦИАНПРОИЗВОДНЫХ 6-(4-БРОМФЕНИЛ)ИМИДАЗО[2,1-B][1,3,4]ТИАДАИЗОЛA

Исследовано реакция электрофильного замещения 2-бром-6-(4-бромфенил)имидазо [2,1-b][1,3,4]тиадиазола с роданидом калия в присутствии молекулярного брома. Показано, что введенные заместители вступают в С(5)-Н положение имидазольной фрагменте исследуемого гетероцикла. Строения впервые полученного соединения установлено методом ИК-, ЯМР 1Н и 13С – спектроскопии, а состав элементным анализом.

Polymeric proton exchange media with ionic bonds in the main chain of the polymer

This paper proposes a method of obtaining the first representative of a polymeric proton-conducting medium with protic ionic groups in the main chain of a polymer by the mutual neutralization of linear telechelic oligomers with end groups of the basic and acidic nature. Oligoethylene oxide containing 1-(3-aminopropyl) imidazole fragments with two types of basic centers (aliphatic secondary amine groups and imidazole fragments) at the ends of the chain was used as the oligomer with basic properties. Sulfonic acid-terminated oligoethylene oxide was used as the acid oligomer. Protonation of aliphatic secondary amino groups in the composition of the oligomer of the basic type with the formation of an ion-elongated polymer chain is more probable at the equimolar ratio of the starting compounds according to the analysis of ΔKa values. It is shown that the synthesized polymer contains two types of crystalline formations with melting points of 37.6 °C and 46.2 °C and turns into a liquid state, when heated to higher temperature values. The proton conductivity of the polymer under anhydrous conditions is close to the conductivity of the initial sulfonic acid-terminated oligomer in the temperature inter val of 40-100 °C and reaches 2.3 · 10–4 S/cm at 100 °C, despite a much lower content of proton charge carriers.

Platinum nanoparticles stabilized by N-heterocyclic thiones. Synthesis and catalytic activity in mono- and di-hydroboration of alkynes.

N-Heterocyclic Thiones (NHT) proved to be efficient ligands for the stabilization of small platinum nanoparticles (1.3-1.7 nm), synthesized by decomposition of [Pt(dba)2], under a H2 atmosphere, in the presence of variable sub-stoichiometric amounts of the NHT. Full characterization by means of TEM, HR-TEM, NMR, ICP, TGA and XPS have been carried out, providing information about the nature of the metal nanoparticles and the interaction of the NHT ligands to the metal surface. Importantly, DFT calculations indicate that some NHT ligands interact with the metal through the C[double bond, length as m-dash]C double bond of the imidazole fragment in addition to the sulfur atom, thus providing additional stabilization to the nanoparticles. According to XPS, TGA and ICP techniques, the surface coverage by the ligand increases by decreasing the size of the substituents on the nitrogen atom. The platinum nanoparticles have been used as catalyst in the hydroboration of alkynes. The most active system is that with a less covered surface area lacking an interaction of the ligand by means of the C[double bond, length as m-dash]C double bond. This catalyst hydroborates alkynes with excellent selectivities towards the monoborylated anti-Markovnikov product (vinyl-boronate) when one equiv. of borane is used. Very interestingly, aliphatic alkynes undergo a second hydroborylation process leading to the corresponding 1,1- and 1,2-diboroylated species with good selectivities towards the former.

Imidazole‐Bridged Tetrameric Group(IV) Heteroleptic Complexes from the Spontaneous Metal‐Ligand Assembly of a Potentially N4‐Tetradentate Ligand

The imidazole‐containing N4‐tetradentate ligand N‐(2‐(1H‐imidazol‐2‐yl)‐3‐(pyridin‐2‐yl)propyl)‐2,6‐diisopropylaniline (L2H) and its N‐benzyl‐protected variant (L2Bn) at the imidazole fragment have been synthesized and fully characterized. Both molecules contain an unresolved Csp3 stereogenic center. The coordination behavior of the newly prepared ligands towards group IV metal ions (MIV = Zr, Hf) has been examined through multinuclear 1H and 13C{1H} NMR spectroscopy and selected single‐crystal X‐ray structural analyses. The ability of the imidazole fragment to enter the metal coordination sphere as a neutral or a monoanionic system has also been investigated, unveiling quite original coordination modes as well as unexpected molecular architectures. When one N imidazole atom is blocked by a benzyl protecting group (L2Bn), the ligand reaction with MIV(NMe2)4 (MIV = Zr, Hf) as metal precursor gives rise to discrete monometallic tris(dimethylamido) 5‐coordinated compounds of general formula L2BnM(NMe2)3. The ligand chelates the metal ion as a bidentate monoanionic κ2{N–,N} system through the imidazole moiety and the anilido N donor while an uncoordinated picolyl arm dangles away from the metal center. Upon coordination to the metal ion, the unprotected L2H undergoes a unique self‐assembly of the chiral racemic ligand to generate an achiral tetrameric network featuring a regularly alternating (R*,S*,R*,S*) configuration around the 6‐coordinated metal centers. The resulting bis(dimethylamido) tetrameric architectures of formula [L2HM(NMe2)2]4 named “poker complexes” contain the imidazole fragment of each ligand bridging two adjacent MIV ions in a µ‐κ{N}:κ{N–} coordination hapticity. At the same time, the picolyl fragments of each chelating L2H ligand “sting” a neighboring metal center as unconventional scorpion's tails that impose further rigidity to the tetrameric structure.

Biomimetic Non-Heme Iron-Catalyzed Epoxidation of Challenging Terminal Alkenes Using Aqueous H2O2 as an Environmentally Friendly Oxidant.

Catalysis mediated by iron complexes is emerging as an eco-friendly and inexpensive option in comparison to traditional metal catalysis. The epoxidation of alkenes constitutes an attractive application of iron(III) catalysis, in which terminal olefins are challenging substrates. Herein, we describe our study on the design of biomimetic non-heme ligands for the in situ generation of iron(III) complexes and their evaluation as potential catalysts in epoxidation of terminal olefins. Since it is well-known that active sites of oxidases might involve imidazole fragment of histidine, various simple imidazole derivatives (seven compounds) were initially evaluated in order to find the best reaction conditions and to develop, subsequently, more elaborated amino acid-derived peptide-like chiral ligands (10 derivatives) for enantioselective epoxidations.

Novel (2-amino-4-arylimidazolyl)propanoic acids and pyrrolo[1,2-c]imidazoles via the domino reactions of 2-amino-4-arylimidazoles with carbonyl and methylene active compounds.

The unexpectedly uncatalyzed reaction between 2-amino-4-arylimidazoles, aromatic aldehydes and Meldrum’s acid has selectively led to the corresponding Knoevenagel–Michael adducts containing a free amino group in the imidazole fragment. The adducts derived from Meldrum’s acid have been smoothly converted into 1,7-diaryl-3-amino-6,7-dihydro-5H-pyrrolo[1,2-c]imidazol-5-ones and 3-(2-amino-4-aryl-1H-imidazol-5-yl)-3-arylpropanoic acids. The interaction of 2-amino-4-arylimidazoles with aromatic aldehydes or isatins and acyclic methylene active compounds has led to the formation of pyrrolo[1,2-c]imidazole-6-carbonitriles, pyrrolo[1,2-с]imidazole-6-carboxylates and spiro[indoline-3,7'-pyrrolo[1,2-c]imidazoles], which can be considered as the analogues of both 3,3’-spirooxindole and 2-aminoimidazole marine sponge alkaloids.