5-bromonicotinic Acid Research Articles

Structural, electronic, intermolecular interaction, reactivity, vibrational spectroscopy, charge transfer, Hirshfeld surface analysis, pharmacological and hydropathy plot on 5-Bromo nicotinic acid – Antiviral study (Hepatitis A, B, and C)

The therapeutic properties of 5-Bromonicotinatic acid (5BNA) were studied for antiviral illnesses like Hepatitis A, Hepatitis B and Hepatitis C and the influence of electron-donating and electron-withdrawing properties of functional groups on the nicotinic acid was evaluated and represented in this study using the DFT approach. The molecular parameters were determined for both gases as well as for various solvent phases. The reactive areas in the compound are examined utilising Fukui analysis. The molecular interactions are accomplished by recognising the different types of bonding found in the compound using the AIM, ELF, LOL, RDG and IRI. Solvation investigations were demonstrated to have an influence on molecular orbital energy, ESP, UV–Vis and NLO analyses. Electron-hole, NBO and Hirshfeld investigations are used to investigate the transfer of charges and interactions inside the molecule. The method of vibrational spectroscopy (IR and Raman) is used to differentiate and identify the various types of vibrations displayed by the compound. The hydropathy plots for the proteins 2A4O, 6CWD and 2OC8 associated with Hepatitis A, Hepatitis B and Hepatitis C illustrate the disquiet and attraction of the amino acids towards the water.

New 3D metal–organic framework isomer containing trinuclear oxo-centered mixed valence iron

Reaction of FeCl2·4H2O, 5-bromonicotinic acid and 4,4′-bipyridine under hydrothermal conditions produced a new isomer of [(Fe iii )2Fe ii (μ3-O)(5-bromonicotinato)6]n, which represented 3D metal–organic covalent framework with trinuclear oxo-centered mixed valence iron clusters. Crystal structure of the isomer has been characterized by single crystal X-ray diffraction data and found distinct from the one for the known isomer with 2D structure.

Multifunctional coordination compounds based on lanthanide ions and 5-bromonicotinic acid: magnetic, luminescence and anti-cancer properties

Four novel coordination compounds based on 5-bromonicotinic acid and lanthanide(iii) ions with interesting magnetic and luminescence properties, and a complete absence of cytotoxicity.

Construction and structural diversification of eight rare-earth MIII coordination complexes with 5-bromonicotinic acid N-oxide

A series of eight MIII (PrIII, SmIII, NdIII, EuIII, GdIII, YIII, ErIII, and YbIII) coordination complexes were assembled from the 5-bromonicotinic acid N-oxide ligand (Hbno) under similar method. Single-crystal X-ray diffraction shows that these complexes display 1-D or bimetallacyclic coordination motifs, respectively. These structural discrepancies may be attributed to the radii of MIII ions, as well as their diverse affinities to N-oxide group. Furthermore, these lower-dimensional coordinative arrays can be further extended via additional secondary interactions, such as H-bonding and aromatic stacking interactions. All samples have been characterized by elemental analyses, and powder X-ray diffraction techniques. In addition, the luminescence sensing ability of 4 was investigated in detail.

Assembling supramolecular networks by halogen bonding in coordination polymers driven by 5-bromonicotinic acid

A series of six coordination compounds {[Zn(5-Brnic)2]·1.5H2O}n (1), [Cd(5-Brnic)2]n (2), [Co(5-Brnic)2(H2O)2]n (3), [Zn(5-Brnic)2(H2biim)]n (4), {[Cd(5-Brnic)2(phen)]·H2O}n (5), and [Pb(5-Brnic)2(phen)] (6) have been generated by the hydrothermal method from the metal(II) nitrates, 5-bromonicotinic acid (5-BrnicH), and an optional ancillary 1,10-phenanthroline (phen) or 2,2′-biimidazole (H2biim) ligand. All the products 1–6 have been characterized by IR spectroscopy, elemental, thermal, powder and single-crystal X-ray diffraction analyses. Their 5-bromonicotinate-driven structures vary from the 3D metal-organic framework with the seh-3,5-P21/c topology (in 2) and the 2D interdigitated layers with the sql topology (in 1 and 3), to the 1D chains (in 4 and 5) and the 0D discrete monomers (in 6). The 5-bromonicotinate moiety acts as a versatile building block and its tethered bromine atom plays a key role in reinforcing and extending the structures into diverse 3D supramolecular networks via the various halogen bonding Br⋯O, Br⋯Br, and Br⋯π interactions, as well as the N–H⋯O and C–H⋯O hydrogen bonds. The obtained results demonstrate a useful guideline toward engineering the supramolecular architectures in the coordination network assembly under the influence of various halogen bonding interactions. The luminescent (for 1, 2, 4, 5, and 6) and magnetic (for 3) properties have also been studied and discussed in detail.

Distinct 2-D and 3-D Co(II) coordination polymers with 5-bromonicotinate induced by different synthetic approaches

Two distinct Co(II) coordination polymers [Co(L-Br)2(H2O)2]n (1) and {[Co(L-Br)2(H2O)0.5](H2O)0.5}n (2) have been prepared from 5-bromonicotinic acid (HL-Br) by using different synthetic approaches (ambient condition vs hydrothermal method). Both complexes have been characterized by elemental analysis, IR, and powder X-ray diffraction. Single crystal X-ray diffraction reveals that 1 displays a 2-D (4,4) polymeric layered network whereas 2 presents a 3-D unusual binodal (3,6)-connected net of (3.4.5)(32.44.55.62.72) topology. Their structural divergences should be properly attributed to the different coordination patterns of L-Br− and water ligands. In addition, thermal stability and magnetic properties of both complexes are also studied.

Exceptional Crystallization Diversity and Solid‐State Conversions of CdII Coordination Frameworks with 5‐Bromonicotinate Directed by Solvent Media

A series of nine coordination polymers {[Cd(L)(2)(solvent)(x)](solvent)(y)}(n) have been prepared from Cd(NO(3))(2) and 5-bromonicotinic acid (HL) in different solvents through a layered diffusion method. By using CH(3)OH/H(2)O at different volume ratios of 1:1 and 1:3, a one-dimensional (1D) coordination species (1a) and a three-dimensional (3D) (3,6)-connected framework (2a·g(1)) can be obtained. A similar self-assembly process in C(2)H(5)OH/H(2)O or H(2)O/1,4-dioxane gives 2a·g(2) or 2a·g(3), which are isomorphic to 2a·g(1) but with different lattice solvents. Replacement of the mixed solvents with DMF/H(2)O (v/v 1:1 or 1:3) also gives a 1D chain complex (1b) or a 3D microporous framework (2b·g(1)). Similarly, MOF 2b·g(2) can be assembled from CH(3)CN/H(2)O as an isomorphic solvate of 2b·g(1). Significantly, the 3D MOF families of 2a·g(n) and 2b·g(n) are supramolecular isomers even though they are topologically equivalent. Also, if a mixture of CH(3)OH/CH(2)Cl(2) (v/v 1:1 or 3:1) is used, a pair of distinct MOFs (3a·g) and (3b) are generated as pseudo-polymorphs that show a two-dimensional (2D) sheet and a 3D coordination framework, respectively. Furthermore, mutual solvent-induced conversions were realized between 1a and 1b and between 2a·g(1), 2a·g(2), and 2a·g(3) following the size-dependent rule of the solvent. These results are of great significance in recognizing the solvent effect upon coordination assemblies and their crystal transformations.

Novel metal–organic frameworks based on 5-bromonicotinic acid: Multifunctional materials with H2 purification capabilities

Two new metal–organic frameworks based on 5-bromonicotinic acid complexes [Cd(5-BrNic)2]n (1) and [Co(5-BrNic)2(H2O)]n (2) have been synthesized by hydrothermal reactions of this ligand with cadmium and cobalt metallic(II) salts in the presence of water. Compound 1 displays intense photoluminescence properties in the solid state at room temperature, while 2 exhibits an antiferromagnetic interaction between Co(II) ions with a J value of −4.1 cm−1. Experimental studies, backed up by Monte Carlo simulations about adsorption, pore size distribution and accessible surface area reveal the capability of 2 for H2 purification applications.

Synthesis, Crystal Structure and Antibacterial Activity of 5-Bromonicotinic Acid [1-(4-Chlorophenyl)methylidene]hydrazide Monohydrate Methanol Solvate

The compound 5-bromonicotinic acid [1-(4-chlorophenyl)methylidene]hydrazide monohydrate methanol solvate, derived from the condensation reaction of 5-bromonicotinic acid hydrazide with 4-chlorobenzaldehyde in a methanol solution, was synthesized and characterized by elemental analysis, IR spectrum, 1H NMR and X-ray single crystal determination. The compound crystallizes in the triclinic space group P − 1 with unit cell dimensions a = 6.9360(14) A, b = 10.070(2) A, c = 12.267(3) A, α = 84.39(3)°, β = 86.10(3)°, γ = 80.50(3)°, V = 839.8(3) Ǻ3, Z = 2, R 1 = 0.0724, and wR 2 = 0.1720. X-ray structure determination reveals that the compound has a trans configuration with respect to the C=N double bond or C–N single bond. In the crystal structure, molecules are linked through intermolecular O–H···N, O–H···O, and C–H···O hydrogen bonds, forming layers parallel to the ab plane. The preliminary biological tests show that the compound has excellent antibacterial activity. The compound 5-bromonicotinic acid [1-(4-chlorophenyl)methylidene]hydrazide monohydrate methanol solvate, derived from the condensation reaction of 5-bromonicotinic acid hydrazide with 4-chlorobenzaldehyde in a methanol solution, was synthesized and characterized by elemental analysis, IR spectrum, 1H NMR and X-ray single crystal determination. The molecule of the compound has a trans configuration with respect to the C=N double bond or C–N single bond. In the crystal structure, molecules are linked through intermolecular O–H···N, O–H···O, and C–H···O hydrogen bonds, forming layers parallel to the ab plane. The preliminary biological tests show that the compound has excellent antibacterial activity.

Fast and Efficient Access to a Family of Multifunctional 1,3,5-Trisubstituted Piperidines

A collection of new 1,3,5-trisubstituted piperidines has been synthesized starting from the commercially available 5-bromonicotinic acid. A unified, diastereoselective strategy allows the controlled access to both cis and trans stereochemistries. The heterocyclic compounds thus prepared bear multiple functional groups suitable for structural diversification and combichem protocols.

Astatine-211 labeling of insulin: Synthesis and preliminary evaluation in vivo and in vitro

A first attempt to label insulin, a small protein with significant affinity to tumors with the α-emitter 211At was performed by an indirect method using N-succinimidyl 5-(tributylstannyl)-3-pyridinecarboxylate (SPC) as a bi-functional linker, and the stability of the conjugated insulin (211At-insulin) was evaluated in vitro and in vivo. SPC was synthesized by using 5-bromonicotinic acid as the starting material. With this bi-functional linker, insulin was conjugated with 211At in a labeling yield of 30–40%, with radiochemical purity of more than 98%. After 24 hours at room temperature, the radiochemical purity was still more than 95%, implying that 211At-insulin is fairly stable in vitro. Biodistribution of 211At-insulin was investigated in NIH strain mice. 211At accumulated rapidly in the liver post injection, with the maximum uptake of 4.29%I.D/g at 30 minutes, and was mainly excreted by kidney. More importantly, 211At-insulin uptake in some key organs or tissues, especially in thyriod, stomach, lung and spleen, was much less than that of free astatide (211At−). This result indicated that 211At-insulin has considerable stability in vivo as well as in vitro.

Unusual Sterically Controlled Regioselective Lithiation of 3-Bromo-5-(4,4‘-dimethyl)oxazolinylpyridine. Straightforward Access to Highly Substituted Nicotinic Acid Derivatives

[Structure: see text] Lithiation of 5-bromonicotinic acid protected as secondary or tertiary amide as well as (4,4'-dimethyl)oxazoline with lithium amides is reported. The unusual C-2 and C-4 regioselective lithiation of 3-bromo-5-(4,4'-dimethyl)oxazolinylpyridine using LTMP versus LDA was observed, providing a new route to substituted nicotinic acid scaffolds. The methodology was applied to the synthesis of novel C-4 and C-6 arylated 5-bromonicotinic acids.

Lanthanide molecular-based hybrids covalently bonded with silica: Photoluminescence and control of micromorphology

The syntheses of modified 5-bromonicotinic acid by (3-aminopropyl)triethoxysilane and the preparation of their corresponding organic–inorganic molecular-based hybrid material with the two components equipped with covalent bonds are described. The organic moiety is a derivative of 5-bromonicotinic acid which is applied to coordinate to RE 3+ and further introduced into silica matrices by Si–O bonds after hydrolysis and polycondensation processes. Judd–Ofelt theory proves that covalency increases along with increasing reciprocal energy difference between the 4fN and 4fN-15d1configurations. Ultraviolet absorption, phosphorescence and luminescence spectra were utilized to characterize the photophysical properties of the obtained hybrid material and the above spectroscopic data reveal that the triplet energy of modified 5-bromonicotinic acid matches with the emissive energy level of RE 3+. In this way, the intramolecular energy transfer process took place within these molecular-based hybrids and strong green, red or blue emissions of RE 3+ have been acquired. Scanning electronic microscope presents no phase separation phenomenon appear and the different crystal structures of lanthanide complex precursor molecules have influence on the microstructure and micromorphology of corresponding molecular hybrids.

Radioiodination of insulin using N-succinimidyl 5-(tributylstannyl)-3-pyridine-carboxylate (SPC) as a bi-functional linker: Synthesis and biodistribution in mice</p> </p>

Insulin receptors are overexpressed on a number of human tumors, leading to significant affinity of insulin to these tumors. It is appealing to receptor-targeted radiotherapy for malignant tumors if insulin is labeled with suitable radionuclide. In this paper, N-succinimidyl 5-(tributylstannyl)-3-pyridinecarboxylate (SPC), a potential bi-functional linker for radioiodination of proteins or peptides, was synthesizedby using 5-bromonicotinic acid as the starting material. Then, with this bi-functional linker, insulin was conjugated with 131I, and the tissue distribution of the labeled insulin (131I-SIPC-insulin) in normal mice was investigated. The results showed that insulin could be conjugated with131I using SPC as the linker in a labeling yield of40-58%, and with radiochemical purity of more than 98% after purification bySephadexOG-10. Even kept at room temperature for 72 hours, the radiochemical purity of 131I-SIPC-insulin was still more than 97%, implying that the conjugated insulin was constantly stable in vitro.Meanwhile, in order to evaluate the in vivo stability of the conjugated compounds, insulin was also labeled with 131I by a direct method using chloramine-T (Ch-T) as the electrophilic agents.Biodistribution of131I-SIPC-insulinin micesuggested that 131I could clear rapidly from the blood,mainly excreted by kidney. However, 131I uptake of mice with131I-SIPC-insulin in some key organs, especially in thyroid and stomach, were much less (150 or 30 times) than that with the direct labeled insulin (131I-insulin). Additionally, it was noted that 131I-SIPC-insulin hasmuch betterinvivo stability than131I-insulin.

Suzuki coupling reaction for the solid-phase preparation of 5-substituted nicotinic acid derivatives

The application of the Suzuki coupling reaction to the preparation of small combinatorial libraries using 5-bromonicotinic acid as a scaffold onto three different types of solid support (Wang, Rink, and BAL resin) is described.

Different crystal structure and photophysical properties of lanthanide complexes with 5-bromonicotinic acid

Five novel lanthanide (Eu3+ (1), Tb3+ (2), Sm3+ (3), Dy3+ (4) and Gd3+ (5)) complexes with 5-Bromonicotinic acid (5-Brnic) were synthesized and two of them (Tb3+, Sm3+) were characterized by X-ray diffraction. The results reveal that {[Tb(5-Brnic)3(H2O)3]·H2O}n (2) and [Sm(5-Brnic)3(H2O)2·H2O]2 (3) exhibit different coordination geometries and crystal structures. Complex 2 has a one-dimensional chain-like polymeric structure through the bridged 5-Brnic anions which links up two neighboring terbium ions, while Complex 3 forms a dimeric molecular structure. The lowest triplet state energy of 5-Brnic was determined to be 24330cm−1 corresponded to the 0–0 transition in the phosphorescence spectrum of its gadolinium complex at 411nm. The strong luminescent emission intensities of these complexes indicated that the triplet state energy of 5-Brnic is suitable for the sensitization of luminescence of Eu3+, Tb3+, Sm3+ and Dy3+, especially for that of Tb3+ and Dy3+.

Direct Space Structure Solution Applications.

The crystal structures of 2,4,6-triisopropylbenzenesulfonamide, 1,2,3-trihydroxybenzene-hexamethylenetetramine (1/1), 5-bromonicotinic acid and chlorothalonil form II have been solved from x-ray powder diffraction data, by application of a direct space structure solution approach using the Monte Carlo method and confirmed by Rietveld refinement. In the sulfonamide, the molecules are linked by N–H⋯O hydrogen bonds into two-dimensional sheets built from alternating eight and twenty-membered rings. In the cocrystal, the molecules are linked by O–H⋯N hydrogen bonds to form puckered molecular ribbons that are in turn linked into a continuous 3D framework by C–H⋯π (arene) interactions. 5-bromonicotinic acid also displays atypical hydrogen-bonding behaviour by formation of dimers through a self-complementary acid-acid hydrogen-bond motif that are connected into antiparallel ribbons by C–H⋯O and C–H⋯N hydrogen bonds. Structure determination of the cocrystal and the bromonicotinic acid was successful despite the presence of preferred orientation in the data, whereas the distortion of the chlorothalonil data was so severe that structure solution was only possible when the effects of preferred orientation were minimized. Both the disordered structure, and an ordered structural approximation of chlorothalonil form II have been determined and rationalized.

A Combination of X-ray Single-Crystal Diffraction and Monte Carlo Structure Solution from X-ray Powder Diffraction Data in a Structural Investigation of 5-Bromonicotinic Acid and Solvates Thereof

The crystal structures of 5-bromonicotinic acid ethylacetate 1, 5-bromonicotinic acid acetonitrile 2, and 5-bromonicotinic acid methanol 3 (all of which were obtained from single-crystal data) and of 5-bromonicotinic acid 4 (solved from powder diffraction data using a direct-space method based on the Monte Carlo technique) are presented; in 1−3, heteromeric N-H···O/C-H···O hydrogen-bonds lead to infinite polar chains of 5-bromonicotinic acid, whereas in 4, the principal noncovalent connector (head-to-head acid···acid hydrogen bonds) generates centrosymmetric dimers.

Syntheses of Selected Quaternary Phenacylbromopyridinium Compounds and their Biological Evaluation

The studies, presented here, deal with the synthetic modification of 5-bromonicotinic acid on its nitrogen nucleus. The synthetic transformations were carried out by reacting equimolar amounts of 5-bromonicotinic acid and phenacyl halides in acetone. A range of phenacyl halides were used with the objective of getting a variety of quaternary ammonium salts of 5- bromonicotinic acid derivatives as multipurpose biologically active compounds. Twelve quaternary ammonium salts of 5-bromonicotinic acid have been synthesized and tested for cytotoxicity, antibacterial and antifungal activities. These compounds showed promising cytotoxicity against Artemia salina. Two compounds, 3-carboxy-1-(4′-methylphenacyl)-5-bromopyridinium bromide (2) and 3-carboxy-1-(4′-nitrophenacyl)-5-bromopyridinium bromide (12), were highly active against Gram-positive and Gram-negative bacteria among all the tested compounds. All the compounds were examined for antifungal activity against fifteen fungal cultures, but none of these compounds proved to be effective against these fungi. The parent compounds and its derivatives were also examined for their effect on mean arterial blood pressure in anaesthetized rats. Compounds 7 and 8 were found to be twofold more active than the parent compound. The rest of the products showed blood pressure lowering effects comparable to the parent compound. All compounds were characterised via elemental analysis UV, IR , mass and 1H NMR spectroscopy.

Iodopyridine-for-iodobenzene substitution for use with low molecular weight radiopharmaceuticals: application to m-iodobenzylguanidine.

Substituting a pyridine ring for a benzene ring in the acylation agent N-succinimidyl 3-iodobenzoate has resulted in a useful approach for the radiohalogenation of monoclonal antibodies, peptides, and labeled biotin conjugates. It was hypothesized that such a substitution in m-iodobenzylguanidine (MIBG), a radiotracer used in the detection and treatment of neuroendocrine tumors, might result in an analogue with more rapid normal tissue clearance, thereby facilitating its use for tumor therapy. For the preparation of this analogue, 3-guanidinomethyl-5-iodopyridine (GMIP; 9b), the silicon precursor 4 was synthesized starting from 5-bromonicotinic acid. Attempts to convert 4 to 9b under various conditions were not successful. Radioiodinated 9b could be prepared by the iododestannylation of the tin precursor 8 in 65-70% radiochemical yield. A number of in vitro, in vivo, and ex vivo studies showed that pyridine-for-benzene substitution in MIBG yielded a compound that no longer was taken up by the uptake-1 pathway.