S-triazine Core Research Articles

Design and synthesis of C3-symmetric polymers with triazine-core and acetamide-linkers eliminating mobile genetic elements

A new class of C3-symmetric polymers with a s-triazine core hybrid and three acetamide linkers was successfully prepared from the etherification of acetamide derivatives Ace-1–4 with 1,3,5-tris-(4-hydroxyphenyl)triazine (THT), resulting in C3-symmetric polymers PTriAce-1–4. The precursor THT was synthesized through cyclotrimerization in the present superacid, while Ace-1–4 was synthesized through the condensation of chloroactyl chloride and different diamine derivatives. The synthesized C3-symmetric polymers were characterized by investigating their FT-IR, PXRD, SEM, and EDX mapping. These characterization techniques showed semi-crystalline structures, homogeneous distribution of microparticles, and good thermal stability as displayed by TGA. The preliminary results suggest that PTriAce-1 demonstrates substantial antibacterial efficacy against a diverse array of pathogenic strains and eliminates the mobilization of mobile genetic elements. The results indicate that this polymer interferes with S. aureus temperate bacteriophage 80α and affects their replication. This indicates the potential of these polymers as important agents in eliminating pathogens, bacteriophage replication, and the growth of antibiotic-resistant bacteria.

Mechanochemical synthesis of a red luminescent coordination polymer from a polydentate quinoline ligand with large conjugation

Abstract A red luminescent coordination polymer has been prepared from a polydentate 8-hydroxyquinoline ligand via mechanochemical synthesis. The obtained coordination polymer is micro/nano spherical and can suspend stably in organic solvents after ultrasonic treatment. Due to the large conjugation of the ligand with a strong polar s-triazine core, the coordination polymer shows a largely red-shifted emission relative to the ligand. The photoluminescence peak of the coordination polymer in organic solvent is at 613 nm, while a largely red-shifted photoluminescence peak at 675 nm and a shoulder peak at 770 nm are found in the photoluminescence spectrum of the coordination polymer in solid due to the strong interchain interaction.

Centripetal triazine chromophores: towards efficient two-photon absorbers and highly emissive polyimide films

Centripetal chromophores based on the s-triazine core with tuneable properties and excellent two-photon absorption properties were used for the construction of high-quality and well-transparent emissive polyimide films.

Synthesis, Structure and Biological Evaluations of Zn(II) Pincer Complexes Based on S-Triazine Type Chelator.

2,4-bis (3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazine (BPMT) pincer ligand was used to synthesize the new [Zn(BPMT)(NCS)2] (1) and [Zn(BPMT)(Br)2] (2) complexes by a reaction with Zn(NO3)2·6H2O in the presence of either KSCN or KBr, respectively. The structure of complex 1 has been exclusively confirmed using single crystal X-ray diffraction. In this neutral heteroleptic complex, the BPMT is a pincer chelate coordinating the Zn(II) ion via three interactions with the two pyrazole moieties and the s-triazine core. Hence, BPMT is a tridentate NNN-chelate. The coordination environment of Zn(II) is completed by two strong interactions with two terminal SCN− ions via the N-atom. Hence, the Zn(II) is penta-coordinated with a distorted square pyramidal coordination geometry. Hirshfeld analysis indicated the predominance of H…H, H…C and N…H intermolecular interactions. Additionally, the S…H, S…C and S…N contacts are the most significant. The free ligand has no or weak antimicrobial, antioxidant and anticancer activities while the studied Zn(II) complexes showed interesting biological activity. Complex 1 has excellent antibacterial activity against B. subtilis (2.4 μg/mL) and P. vulgaris (4.8 μg/mL) compared to Gentamycin (4.8 μg/mL). Additionally, complex 1 (78.09 ± 4.23 µg/mL) has better antioxidant activity than 2 (365.60 ± 20.89 µg/mL). In addition, complex 1 (43.86 ± 3.12 µg/mL) and 2 (30.23 ± 1.26 µg/mL) have 8 and 12 times the anticancer activity of the free BPMT ligand (372.79 ± 13.64 µg/mL).

Recent Advances in the Biological Activity of s-Triazine Core Compounds.

An effective strategy for successful chemotherapy relies on creating compounds with high selectivity against cancer cells compared to normal cells and relatively low cytotoxicity. One such approach is the discovery of critical points in cancer cells, i.e., where specific enzymes that are potential therapeutic targets are generated. Triazine is a six-membered heterocyclic ring compound with three nitrogen replacing carbon-hydrogen units in the benzene ring structure. The subject of this review is the symmetrical 1,3,5-triazine, known as s-triazine. 1,3,5-triazine is one of the oldest heterocyclic compounds available. Because of its low cost and high availability, it has attracted researcher attention for novel synthesis. s-Triazine has a weak base, it has much weaker resonance energy than benzene, therefore, nucleophilic substitution is preferred to electrophilic substitution. Heterocyclic bearing a symmetrical s-triazine core represents an interesting class of compounds possessing a wide spectrum of biological properties such as anti-cancer, antiviral, fungicidal, insecticidal, bactericidal, herbicidal and antimicrobial, antimalarial agents. They also have applications as dyes, lubricants, and analytical reagents. Hence, the group of 1,3,5-triazine derivatives has developed over the years. Triazine is not only the core amongst them, but is also a factor increasing the kinetic potential of the entire derivatives. Modifying the structure and introducing new substituents makes it possible to obtain compounds with broad inhibitory activity on processes such as proliferation. In some cases, s-triazine derivatives induce cell apoptosis. In this review we will present currently investigated 1,3,5-triazine derivatives with anti-cancer activities, with particular emphasis on their inhibition of enzymes involved in the process of tumorigenesis.

S-Triazine: A Privileged Structure for Drug Discovery and Bioconjugation.

This review provides an overview of the broad applicability of s-triazine. Our many years working with this intriguing moiety allow us to discuss its wide activity spectrum (inhibition against MAO-A and -B, anticancer/antiproliferative and antimicrobial activity, antibacterial activity against MDR clinical isolates, antileishmanial agent, and use as drug nano delivery system). Most of the compounds addressed in our studies and those performed by other groups contain only N-substitution. Exploiting the concept of orthogonal chemoselectivity, first described by our group, we have successfully incorporated different nucleophiles in different orders into s-triazine core for application in peptides/proteins at a temperature compatible with biological systems.

In situ preparation of composites based on trishydrazino-s-triazine (1,4-/1,3-) benzene dicarboxyaldehyde with reduced graphene oxide and their electrical conductivity performance

Herein we report a novel covalent triazine framework (CTF) based on the s-triazine core. The CTF was in situ prepared onto the surface of reduced graphene oxide (rGO) via the condensation of trishydrazino-s-triazine with terephthaldehyde (TPA) or isophthaldehyde (IPA) via hydrazone linkage using both conventional heating (CFTx-rGO) and ultrasonic method (CFT1-rGOus). The resistivity and conductivity studies showed that CFT1-rGOus showed a good attachment onto the surface of rGO via the non-covalent functionalization approach (π-π stacking) and showed the highest resistivity materials applications with very promising character, even with high temperature. While the prepared composite using conventional heating CFTx-rGO showed at the room temperature and high-temperature studies, it is the best among the prepared materials for the conductivity.

Synthesis, Anti-proliferative Activity, and Molecular Docking Study of New Series of 1,3-5-Triazine Schiff Base Derivatives.

Based on the use of s-triazine as a scaffold, we report here a new series of s-triazine Schiff base derivatives and their anti-proliferative activity against two cancer cell lines: human breast carcinoma (MCF-7), and colon cancer (HCT-116) compared with tamoxifen as a reference compound. Several derivatives exhibited growth inhibition activity in the sub-micromolar range. The results reveal that the s-triazine Schiff base derivatives showed varied activities and that the substituents on the s-triazine core have a great effect on the anti-proliferative activity. Compounds with a piperidino and benzylamino substituent on the s-triazine moiety 4b and 4c were most effective in both cell lines compared to the reference compound used. In addition, compound 4b has a para chlorine atom on the benzylidine residue, demonstrating the most potent activity with IC50 values of 3.29 and 3.64 µM in MCF-7 and HCT-116, respectively. These results indicate that in general, the nature of the substituents on the triazine core and the type of substituent on the benzilyldene ring significantly influenced the anti-proliferative activity. The results obtained from the anti-proliferative activity and the molecular docking study indicate that s-triazine-hydrazone derivatives may be an excellent scaffold for the development of new anti-cancer agents.

Synthesis and Characterization of New Series of 1,3-5-Triazine Hydrazone Derivatives with Promising Antiproliferative Activity.

A new series of s-triazine hydrazone derivatives was prepared based on the reaction of 6-hydrazino-2,4-disubstituted-s-triazine with p-substituted benzaldehyde derivatives using a straightforward synthetic pathway. The antiproliferative activity of all synthesized compounds was evaluated against two human cancer cell lines; breast cancer MCF-7 and colon carcinoma HCT-116 using MTT assay. Among all, 11 compounds have shown strong to moderate antiproliferative activity with IC50 values in the range 1.01–18.20 µM in MCF-7 and 0.97–19.51 µM in HCT-116. The best results were obtained with 4,4’-(6-(2-(pyridin-2-ylmethylene)hydrazinyl)-1,3,5-triazine-2,4-diyl) dimorpholine 11 (IC50 = 1.0 µM and 0.98 µM in MCF-7 and HCT-116 cell lines, respectively). The substituents on the s-triazine core as well as the substituent at the benzylidene moiety have a great effect on the antiproliferative activity. Whereas compounds containing dimorpholino-s-triazine derivatives 8a–e showed more potent antiproliferative in MCF-7 compared to their analogs 7a–f (compounds containing two-piperidine rings), compounds containing one piperidine and one morpholine ring 9a–f showed better IC50 values in the range 10.4–22.2 µM. On the other hand, compounds containing two-piperidine rings 7a–f showed more potent antiproliferative in HCT-116 (IC50 values in the range 8.8–19.5 µM) than their analogs 8a–e and 9a–f.

Synthesis, X-ray structure, and DFT studies of five- and eight-coordinated Cd(II) complexes with s-triazine N-pincer chelate

The synthesis and spectral characterizations of [CdLCl2] (1) and [CdL(NO3)2(H2O)] (2) pincer complexes of the s-triazine core ligand (L), 2,4-bis(3,5-dimethyl-1H-pyrazol-1-yl)-6-methoxy-1,3,5-triazine), are presented. Complexes 1 and 2 have five- and eight-coordinated Cd(II) ions, respectively, where L acts as a neutral tridentate N-chelate. The coordination sphere is completed by two coordinated Cl– anions in 1 and with one water molecule and two bidentate nitrate anions in 2. The neutral complex units of 1 and 2 are packed by the polar Cl…H and O…H hydrogen bonds, respectively. Using Hirshfeld analysis, the percentages of these contacts are 24.5% and ∼36.8%, respectively. Both complexes showed some anion-π stacking interactions. Thermogravimetric analysis showed that 1 is thermally more stable than 2. The orbital-orbital interactions included in the Cd-Cl, Cd-O, and Cd-N coordinate bonds were analyzed using DFT calculations. The calculated NMR results correlated very well with the experimental data.

Synthesis, molecular structure and DFT studies of two heteroleptic nickel(II) s-triazine pincer type complexes

Two new heteroleptic Ni(II) pincer complexes of s-triazine core ligand (L) were synthesized and characterized. The two complexes [NiL(H2O)2Cl]Cl; (1) and [NiL(H2O)3](ClO4)2.H2O; (2) showed a slightly distorted octahedral configuration around Ni(II), and L acts as a tridentate N-chelate with NiN bonds are generally shorter in 2 than 1. Using atoms in molecules (AIM) theory, the net interaction energies between Ni(II) and L are higher in 2 (96.75 kcal/mol) than in 1 (90.32 kcal/mol). The packing is dominated by O⋯H (45.0%) and Cl⋯H (16.0%) hydrogen bonds, respectively. Both complexes showed different extents of CH⋯O and anion-π stacking interactions. The MPW1PW91/TZVP method was used to predict the electronic properties of complexes 1 and 2. As a result of the interactions between the Ni(II) ion and ligand groups, the charge densities of nickel ion are reduced to 0.76–0.86 e in 1 and 0.87–0.98 e in 2. Also, its spin density is reduced to ∼1.73 e instead of 2.00 e in both complexes. Thermogravimetric analysis showed that 2 exploded at 281 °C in a fashion like the popcorn.

Ultrasound-assisted synthesis of nanocomposites based on aromatic polyamide and modified ZnO nanoparticle for removal of toxic Cr(VI) from water

In this study, novel nanocomposites (NCs) of aromatic polyamide (PA) and surface modified ZnO nanoparticle with s-triazine heterocyclic ring was introduced for efficient removal of toxic hexavalent chromium (VI) from aqueous solution. The surface of ZnO nanoparticle was modified by s-triazine core silane coupling agent (ZnO-TSC) and PA/ZnO-TSC NCs with different amount of ZnO-TSC nanoparticles (0, 5, 10 and 15wt%) were prepared by ultrasonic irradiation. The synthesized PA/ZnO-TSC NCs were characterized by FT-IR, XRD, FE-SEM, TEM and TGA methods. TEM images showed that ZnO nanoparticles were dispersed homogeneously in the polymer matrix. The adsorption experiments were carried out in batch mode to optimize various parameters like contact time, pH and concentration of metal ion that influence the adsorption rate. The maximum uptakes of Cr(VI) at pH 4.0 was 72%, 81%, 89% and 91% for pure PA, NC5%, NC10% and NC15%, respectively. The kinetic of adsorption was investigated and the pseudo second-order model is an appropriate model for interpretation of adsorption mechanism of Cr(VI) ions.

Investigation of photophysical properties of new branched compounds with triazine and benzimidazole units

Three new acceptor–donor–acceptor branched compounds with triazine and benzimidazole units (M1, M2, and M3) were synthesized and characterized by infrared, hydrogen-1 nuclear magnetic resonance, carbon-13 nuclear magnetic resonance, mass spectrometry, and elemental analysis. Their photophysical properties were investigated including linear absorption, single-photon excited fluorescence, fluorescence quantum yield, two-photon absorption, and frequency up-converted fluorescence. When the number of branches increases, the spectral positions of the linear absorption and the single-photon excited fluorescence show red shifts, while the fluorescence quantum yields decrease. When the polarity of solvents increases, the spectral positions of the single-photon excited fluorescence and the Stokes shifts also show red shifts, while the fluorescence quantum yields of the two-branched compound (M2) and three-branched compound (M3) decrease. Under the excitation of an 800 nm laser with a pulse width of 80 fs, all these compounds emit intense green frequency up-converted fluorescence, and the two-photon absorption cross-sections are 210, 968, and 1613 GM for M1, M2, and M3, respectively. This result shows that significant enhancement of the two-photon absorption cross-section can be achieved by sufficient electronic coupling between the strong charge transfer acceptor–donor–acceptor quadrupolar branches through the s-triazine core.

New serinolic amino-s-triazines by chemoselective amination of cyanuric chloride and their (pro)diastereomerism in restricted rotational phenomena

Abstract The highly chemoselective preparation of new elaborated N-unsymmetrically substituted chlorodiamino-s-triazines and melamines, seen as building-blocks for iterative synthesis, is reported. It consisted of amination of cyanuric chloride with commercial C-2-substituted 2-aminopropane-1,3-diols (“serinols”), playing the role as “open-chain” unit and enantiopure (1S,2S)-2-amino-1-(4-nitrophenyl)propane-1,3-diols (“p-nitrophenylserinols”) based amino-1,3-dioxanes (“closed-chain” unit). Issued from the restricted rotation about C(s-triazine)-N(exocyclic) partial double bonds, seen as axes of (pro)diastereomerism, a global four-component rotational equilibrium involving the title compounds is discussed based on DFT computation and (VT) NMR data. Depending on π-deficiency of the s-triazine core, an (un)synchronised deblocking of the generated rotational diastereomers was observed. They are discussed as influence of intra-vs. intermolecular NH...OH (dynamic) interactions occurring in the “open-chain” unit and the anancomeric, axial vs. equatorial, amino-anchorage of the “closed-chain” unit.

Technologically promising, room temperature luminescent columnar liquid crystals derived from s-triazine core: molecular design, synthesis and characterization

Three fold Horner-Wadsworth-Emmons (HWS) reaction of triphosphonate with achiral/chiral 3,4,5-tris(alkoxy)benzaldehydes yield novel achiral/chiral star-shaped liquid crystals (LCs), in which three fluorophore arms such as 1,2,3-tris(alkoxy)-5-styrylbenzenes are tethered to a central s-triazine core. These LCs, the first of their kind, display a columnar liquid crystalline phase over a wide temperature range existing between well below and above the room temperature, which is evidenced by optical and calorimetric studies. Besides, they show photoluminescence both in solution and mesomorphic states. Thus, given their self-organization into fluid one-dimensional columnar array coupled with light generating capability, these organic ordered-fluids can be regarded as novel media for advanced technological applications.

Synthesis, characterization, and optical properties of two-photon-absorbing octupolar molecule with an s-triazine core

The octupolar molecule with s-triazine as the π-electron deficient core, N-ethylcarbazole groups as the electron-donating end-groups, 2,4,6-tris[2-( N-ethyl-3-carbazole)carboxethenyl]-1,3,5- s-triazine(III), was prepared. The assemblies of III, 2,4-dimethyl-6-[2-( N-ethyl-3-carbazole)carboxethenyl]-1,3,5- s-triazine(I), and 2-methyl-4,6-bis [2-( N-ethyl-3-carbazole)carboxethenyl]-1,3,5- s-triazine(II), were also prepared. The linear and nonlinear spectra of these compounds regularly vary: (1) the spectral positions ( λ max values) of the linear absorption, the one-photon excited fluorescence (OPEF) and the two-photon excited fluorescence (2PEF) show regular red-shifts when the branch number increases from I to III; (2) the OPEF and the 2PEF intensities are all increased significantly when going from I to III. Excited by femtosecond laser at 800 nm wavelength, the fluorescence intensities of II, III show a quadratic dependence on the pump intensity, suggesting that the emission originates from a 2PA process. Two-photon absorption (2PA) cross-section of II, III is 397 GM and 994 GW, respectively. The value of σ 2/MW of II, III varies with the ratio of 1.0:1.8.

Synthesis and electrochemical characterization of donor–acceptor phenylazomethine dendrimers

The synthesis of the first donor–acceptor phenylazomethine dendrimers ( 4 and 5 ) is described. A convergent method is used via the condensation of aromatic ketones with an appropriately functionalized tri(aminophenyl)- s-triazine promoted by titanium (IV) chloride. Cyclic voltammetry investigations show a donor–acceptor behaviour due to the presence of the electron acceptor s-triazine core and the donor ability of the conjugated peripheral butoxybenzene units.

Cooperative Enhancement of Two-photon Absorption of Multibranched Compounds with Vinylenes Attaching to the s-Triazine Core

Abstract Two series of multibranched compounds with vinylenes attaching to the s-triazine core have been synthesized. The two-photon absorption cross section (σ) increases significantly as the branch number increases, with the ratios of σ between one-, two-, and three-branched compounds being 1.0:3.3:7.0 for series A and 1.0:3.7:7.0 for series B respectively, indicating remarkable cooperative enhancement.