In this work, stable chemical precursors (3,5-DTBC) and alkylated derivatives were synthesized through strategic modifications guided by the redox and chelation properties of catechol. Leveraging the molecular principle that fusing two bioactive components often yields synergistic effects, catechol — a polyphenol with broad biological activities — was integrated into the nitrogen-containing heterocyclic core structure, imidazolidine-2,4-dione, to design a novel class of hybrid compounds (7a–q) with diverse pharmacological profiles. The primary objective was to explore efficient synthetic routes, characterize structures via physicochemical analyses, and possible evaluate cytotoxicity and AT1-inhibitory activity in vitro.

The impact of substituents at the 4- and 7-positions of 1,10-phenanthroline-2,9-dicarboxamides on the photophysical properties of the ligands and their coordination compounds with the lanthanide triad-europium, gadolinium, and terbium-was analyzed. This study demonstrates how modification of the electronic nature of ligands through the incorporation of diverse functional groups affects the luminescence properties of their complexes. The introduction of various substituents leads to the appearance of intra-ligand or ligand-to-ligand charge transfer (CT) states. The highest luminescence efficiency was observed for LHEu(NO3)3 (Qin = 54.1% and QL = 9.6%), suggesting strong luminescence quenching of the CT state. It was found that a relatively low Delta E (similar to 3000 cm-1) supports direct energy transfer from S1 to T1 bypassing the CT state, even though it is outside Reinhoudt's optimal range. The introduction of fluorines leads to the strongest luminescence quenching among all the substituents. The impact of substituents at the 4- and 7-positions of 1,10-phenanthroline-2,9-dicarboxamides on the photophysical properties of the ligands and their coordination compounds with the triad of lanthanides was analyzed.

A modular synthesis of novel series of 1,7-difluorinated BODIPYs has been elaborated. First, the acid-catalyzed condensation of ethyl 3-aryl-4-fluoro-1H-pyrrole-2-carboxylates with aromatic aldehydes gives the corresponding dipyrromethane-1,9-dicarboxylates. The latter are subjected to the exhaustive reduction with lithium aluminum hydride to transform the ester moieties into methyl groups. The subsequent oxidation of the resulting 1,9-dimethylated dipyrromethanes followed by the boron difluoride complexation afforded a family of novel core-fluorinated BODIPYs in up to 74 % yield. Photophysical properties of the resulting BODIPYs were tuned by varying of the starting fluoropyrroles and aromatic aldehydes and were studied by UV-visible and fluorescence spectroscopy. As a result, the fluorescence quantum yields of the obtained compounds reached up to 99 %. In addition, their ability to generate singlet oxygen and electrochemical properties were also evaluated. As a result, a new promising family of fluorophores with a good combination of the fluorescence and photosensitizing properties was obtained. It was found that conversion of ester groups into methyl ones at the 3,5-positions of the BODIPY core is a crucial step toward fluorescence enhancement. In addition, DFT calculations were performed to elucidate a relationship between electronic structure, geometry and photophysical properties of these BODIPYs. This paper describes a synthetic approach to obtain novel core-fluorinated BODIPYs. The starting 4-fluoropyrroles is transformed into 3,7-difluorinated dipyrromethane-1,9-dicarboxylates. The subsequent exhaustive reduction with LAH, followed by oxidation and boron difluoride complexation, affords 3,5-dimethylated 1,7-difluoro-BODIPYs. As a result, a new promising family of fluorophores with a good combination of the fluorescence and photosensitizing properties has been obtained. image

New octaiodo-substituted lutetium (III) phthalocyanine was prepared using a six-step synthetic procedure starting from commercially available o-xylene. The amide synthesis and dehydration step were optimized. The influence of the nature of peripheral halogen atoms on optical and photochemical properties was studied. For the complex under study, the possibility of participation in photoreactions of types I and II with the formation of two different forms of reactive oxygen species was investigated: superoxide anion radical and singlet oxygen respectively. Competition between two photoreactions was demonstrated. The Z-scan method revealed a pronounced nonlinear optical response of the iodinated complex, caused by the action of heavy atoms of peripheral iodine groups.

Aromatic nitro compounds are important intermediates in synthetic organic chemistry. In this work, catechol was used as raw materials, and nitro‐catechol derivatives with different alkylation substitutions were synthesized using two different synthetic routes. More than 15 new previously undescribed compounds were obtained. Each compound was meticulously characterized using a suite of physicochemical techniques, with selective compounds further analyzed via X‐Ray diffraction to ascertain their structure. These newly synthesized compounds hold significant promise as candidates for further chemical modification, which underlines their potential usefulness in the field of the fine synthesis of organic compounds.

Sodium hydrogen sulfate is proposed as a mild acidic catalyst for the dopamine nitration with sodium nitrite. This reagent system gives nitrodopamine in high yield and excellent purity and is suitable for routine synthesis from milligram to multi-gram scale.

An efficient synthetic protocol for the preparation of novel 1,7-difluorinated BODIPYs was elaborated. A set of novel dipyrromethanes, which are key intermediates for the target dyes, was prepared by acid-catalyzed condensation of ethyl 3-aryl-4-fluoro-1H-pyrrole-2-carboxylates with aldehydes in up to quantitative yield. Subsequent oxidation and boron difluoride complexation under microwave irradiation afforded a family of novel core-fluorinated BODIPYs in up to 92 % yield. Their photophysical properties were studied by UV–visible and fluorescence spectroscopy. In addition, DFT calculations were performed to estimate 2,6-substituents effect. This revealed that the values of the absorption and emission maxima perfectly correlated with the energy gap between the frontier orbitals.

A wide range of 1,10-phenanthroline-2,9-dicarboxylic acid diamides was synthesized, differing in the structure of substituents in the amide function and in the nature of substituents at positions 4 and 7 of the heteroaromatic ring. All new compounds were characterized by NMR, IR spectroscopy, and high resolution mass spectrometry. The molecular structure of one of the ligands was unambiguously confirmed by X-ray diffraction analysis. The solubility of all the obtained compounds in 3-nitrobenzotrifluoride was quantitatively evaluated.

The titular compound was characterized for the first time using a full range of spectroscopic methods, including UV, IR, 1H, and 13C NMR spectra. In solution, all methods showed a keto–enol equilibrium strongly shifted to the enol form. The X-ray structures determined for all simple 2-oxosuccinates showed only the enol form packed as hydrogen-bonded dimer stacks.

A highly efficient synthetic approach was developed for the synthesis of unsymmetrical 1,10-phenanthroline-2,9-diamides with two different substituents in the fourth and seventh positions of the phenanthroline core. The structures of these ligands were confirmed using various spectral methods including 2D-NMR and X-ray analysis. Quantum chemical calculations supported the presence of tautomeric forms of these ligands. Furthermore, it was discovered that these compounds exhibit polydentate ligand behavior toward lanthanide nitrates. The structural characteristics of the complexes formed between these ligands and lanthanide nitrates were investigated both in the solid state and in solution. To further understand the binding properties of these novel unsymmetrical ligands, the binding constants for potential complexes were quantitatively measured by using UV-vis spectrophotometric titration. This allowed for a comprehensive analysis of the binding affinity and stability of these complexes. Extraction experiments of f-elements were performed for symmetrical and unsymmetrical diamides. Overall, this study presents significant advancement in the synthesis and characterization of unsymmetrical 1,10-phenanthroline-2,9-diamides and provides valuable insights into their potential applications as polydentate ligands for lanthanide nitrates.

The reaction of the O,N,N,O-type ligands, namely, 4,7-bis(4- tert -butylphenoxy) 2 -2,9-(HOCRR’CH) 2 -1,10-phenanthrolines, LH 2 (R = R′ = Ph (1) , RR ′ = −(CH 2 ) 5 − (2) , 2,2-adamantylene (3)) , with an equimolar amount of Ti(OPr i ) 4 in toluene under mild conditions afforded the mixtures of the corresponding titanium LTi(OPr i ) 2 (4–6) and titanyl complexes LTi=O (7–9) . Subsequent reflux of these mixtures in toluene gave pure derivatives 7–9 , which were characterized by 1 H and 13 C NMR spectroscopy and elemental analysis. The presence of the Ti=O fragment in molecules 7–9 was unambiguously confirmed by IR spectroscopy data and was found to be consistent with the data of quantum chemical calculations. The new ligand 3 was obtained by sequential treatment of 4,7-di(4- tert -butylphenoxy)-2,9-dimethyl-1,10-phenanthroline with an excess of lithium diisopropylamide and adamantan-2-one. The titanyl complex 7 was found to be moderately active as an initiator of ε-caprolactone polymerization.

1,3-Dipolar cycloaddition of azomethine ylide, generated from isatin and sarcosine, with 5-arylidene-2-thiohydantoins equipped with various chiral substituents at the N3 atom occurs diastereoselectively. The highest selectivity with dr = 5 : 1 was observed for the 2-thiohydantoin bearing 1,2-diphenylethyl substituent.

In this work we report on new examples of phenanthrolindiamides containing asymmetric centers in amide substituents.

AbstractNew pyridyl-containing diarylamines were obtained via Cu-assisted reductive amination of the ortho-2-pyridylarylboronic acids. Comparative analysis of the spectral and electrochemical data obtained for new diarylamines and their pyridyl-free counterparts revealed the intramolecular H-bond (IMHB) formation which significantly influences the properties of the amino group. The electron density at the N atom of the amino group is increased due to partial weakening of the N–H bond, although the BDE and activation energy for the H-atom abstraction is increased due to the chelating effect of two N atoms. The ortho-pyridyl-containing diarylamines are more prone to be oxidized as compared to their pyridyl-free counterparts; the shift in the oxidation potential values correlates with the strength of the intramolecular H-bonding which can be tuned by inserting substituents in the pyridyl or phenyl rings. The IMHB is reserved even in polar solvents having a significant H-acceptor ability (such as DMSO) but can be destroyed in methanol, testifying in favor of the dynamic nature of the H-bonding.

Reprocessing of spent nuclear fuel (SNF) is an important task in a frame of ecology and rational use of natural resources. Uranium, as the main component of SNF (>95%), can be recovered for further use as fresh nuclear fuel. To minimize an amount of solid radioactive waste generated during SNF reprocessing, new extractants are under investigation. Diamides of 1,10-phenanthroline-2,9-dicarboxylic acid are perspective tetradentate N-donor ligands that form strong complexes with f-elements, which are soluble in polar organic solvents. As an example of three ligands of this class, we conducted a comparative study and showed how the substituent in the amide functional group affects the extraction ability toward uranyl nitrate from nitric acid media. We have performed a careful study (NMR, FT-IR, XRD, RMC-EXAFS) of the structures of synthesized complexes of new ligands with uranyl nitrate and used quantum mechanical calculations to explain the discovered regularities through.

An interaction of 2-hydroxy-9(10),16(17),23(24)-tri-tert-butyl-29H,31H- phthalocyanine (1) with hexachlorocyclotriphosphazene (phosphonitrilic chloride trimer) produced, along with the A(3)B type low-symmetry monophthalocyanine (monomer 2), a bis-derivative 3 with spectral characteristics such as that of most clamshell-type phthalocyanines (typically, H-dimers). The reaction can be considered conditionally selective. DFT calculations showed the possibility of the existence of several isomers. Based on the UV-Vis, fluorescent and NMR studies, we found that 3 was obtained as an inseparable mixture of three diastereomers-achiral cis-isomer and two chiral trans-isomers. DFT analysis has also shown that cis-isomer can exist as two rotamers-parallel and oblique, by an analogy with the cofacial J-type dimers that we obtained earlier.

Planar and sandwich-type iodo-substituted phthalocyanines – precursors for cross-coupling reactions were synthesized starting from 4-iodophthalonitrile via a novel user-friendly synthetic strategy. For this purpose, 4-iodophthalonitrile was prepared following the multi-step protocol, including nonclassical version of diazotization/iodination reaction in the presence of p-toluenesulfonic acid. Tetraiodophthalocyaninato Zinc(II) was obtained using a solvent-free microwave-assisted synthesis. For the first time, the polyphosphoric acid was applied to the demetallation of halogen-substituted phthalocyanine complex. Under these conditions, demetallation of Zinc(II) complex occurred in a good yield without the oxidation of peripheral iodogroups. The Sonogashira cross-coupling reaction between the 2(3),9(10),16(17),23(24)-tetraiodophthalocyanine and model (trimethylsilyl)acetylene resulted in a target compound in a high yield (94%). The versatility of iodo-substituted phthalocyanine precursors was demonstrated on the examples of the synthesis of novel tetra-(3-hydroxyprop-1-yn-1-yl)- phthalocyaninato Zinc (II) (52% yield), bis[tetra(2-trimethyhilyethynyl)phthalocyaninato] Lutetium (III) (45% yield). Target compounds were identified by nuclear magnetic resonance, infrared spectroscopy, and mass spectrometry. UV–Vis properties of target compounds were investigated and compared with literature data. The key compounds were characterized by elemental analysis.

A general synthesis of NH-isatin N′-arylimines involves the aza-Wittig reaction of isatin and aryl azides, providing higher E-diastereoselectivity as compared to previously described methods. The procedure is applicable even to anilines which do not directly react with isatins.

For the first time, convenient methods for the preparation of pyrazoline N-alkylidene salts based on terpene (camphor, camphorquinone, carvone) ketones, cage (adamantanone and norcamphor) ketones, and natural aldehydes (carvone and myrtenal) allowing the isolation of stable pyrazolinium salts in individual form were proposed. Optimization of the conditions for the synthesis of the target products was carried out. The antiviral activity of the synthesized salts was studied; among the tested compounds 1-bornylidene-3-phenylpyrazolinium tetrafluoroborate (IC50 6.2 μM, SI 107) exhibited the greatest activity against influenza A/Puerto Rico/8/34 (H1N1) virus.