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In this study, the novel 4-(N,N′-dimethylamino)phenyl substituted lutetium(III) acetate phthalocyanine (2) and its quaternized derivative (3) were synthesized via a Suzuki-Miyaura coupling reaction between tetrakis(iodo) lutetium(III)acetate phthalocyanine (1) and 4-(N,N-dimethylamino)phenylboronic acid, and subsequent quaternization using dimethyl sulfate, respectively. The obtained phthalocyanine 3 exhibited excellent solubility in water which is important for photodynamic therapy applications. Photophysical properties such as fluorescence quantum yield and fluorescence lifetime, and photochemical properties such as singlet oxygen generation and photostability were investigated to determine their suitability for photodynamic therapy. The lutetium(III) phthalocyanines, especially quaternized derivative 3, showed promising properties as potential photosensitizers for the treatment of cancer, producing higher singlet oxygen (ΦΔ = 0.59) than motexafin lutetium (ΦΔ = 0.31) which is a clinically used lutetium texaphyrin photosensitizer.

In an attempt to design and prepare a new library of anticancer candidates, focused thiopropargylated benzothiazole was reacted with ethyl azidoacetate and/or ethyl azidobenzoate to yield newer 1,2,3-triazole-benzothiazole conjugates bearing ester functionality through click chemistry approach. The hydrazinolysis of the obtained ester-based triazoles was also carried out to give the corresponding 1,2,3-triazole acid hydrazide derivatives as precursors for the synthesis of the focused Schiff bases by their condensation with various benzaldehyde derivatives. Spectroscopic study was investigated on the establishment of the structures of all newly synthesized Schiff bases bearing benzothiazole-1,2,3-triazole molecular conjugate. The newly designed hydrazones showed two isomers (cis-E and trans-E) with different isomeric distribution as confirmed by NMR spectral data and supported by DFT carried out in gas phase at B3LYP 6‒311G (d,p) basis set. The DFT results showed that the cis-E isomer is the lower energy structure and this finding was illustrated in terms of the intermolecular H-bonding. These molecules were screened for anticancer activities with A549 and H1299 lung cancer cell lines. The anticancer activities ranged from 55 to 90%. DNA binding study was also carried out to see the mechanism of action and the DNA binding constants were of good value ranging from of 2.0 × 105 and 14.7 × 105 M−1; indicating good interactions of the reported molecules with DNA. Finally, the modeling was confirmed and it was found that the results of modeling were in good agreement with the results of anticancer and DNA binding studies. All these finding confirmed that the reported molecules work as anticancer agents by interacting with DNA.

Despite the availability of some drugs, there is an urgent need for effective anti-cancer medication. It is due to various side effects and non-functionality of the present drugs; especially at the late stage of cancer. Therefore, three series (4a-e, 6a-e and 8a-j; 21 compounds) of benzotriazole-1,2,3-triazole hybrids (carrying different pharmacophores) have been designed and synthesized (by both conventional and microwave syntheses) through the Cu(I)-catalyzed click 1,3-dipolar cycloaddition reaction of the propargylated benzotriazole with the appropriate aliphatic, aromatic and phenyl/benzyl acetamide azides. The syntheses times were from 6 to 12 h and 4 to 8 min in conventional and microwave syntheses. The yields were 80 to 86% and 89 to 95% in conventional and microwave syntheses; confirming microwave synthesis as an economic and eco-friendly method. These compounds were characterized by proper spectroscopic methods. The anticancer activities with A549 and H1299 lung cancer cell lines were in the range of 70.0 to 90.0% for 4a-e series, 78.0 to 90.0% for 6a-e series and 81.0 to 90.0% for 8a-j series. The reported compounds showed good DNA binding constants in the range of 1.3 × 103 to 11.90 × 105 M−1. The docking results suggested strong DNA bindings of the reported compounds in the minor grooves of DNA; through hydrogen bonding and hydrophobic interactions. The quite good anticancer activities and high DNA binding constants have indicated that the reported molecules may be future anticancer agents.

The novel zinc(II) phthalocyanine directly conjugated with 4-(diethylamino)phenyl groups (2) via C C bond formation using Suzuki-Miyaura coupling reaction was synthesized for the first time. This phthalocyanine was converted to the quaternized derivative (3) to enhance its water solubility. The photochemical (singlet oxygen quantum yield and photodegradation quantum yield) and photophysical (fluorescence quantum yield and lifetime) properties of the synthesized novel zinc(II) phthalocyanines (2 and 3) were investigated in DMSO (for both phthalocyanines 2 and 3) and in aqueous solution (for only phthalocyanine 3) for determination of their photodynamic therapy abilities. Additionally, the bovine serum albumin (BSA) binding behavior of the water soluble zinc(II) phthalocyanine (3) was investigated in aqueous solution for determination of transporting capability of this phthalocyanine in the circulatory system.

The symmetrical zinc(II) phthalocyanines conjugated with 9,10-dioctyl-6,7-dimethoxy-2,3-dioxytriptycene or 9,10-diundecyl-6,7-dimethoxy-2,3-dioxytriptycene moieties were synthesized in this study. These novel phthalocyanines were characterized by standard characterization techniques such as 1H-NMR, FT-IR, UV–vis, Mass and Elemental Analysis. All these phthalocyanines showed highly solubility and formed non-aggregated monomeric species in most of the organic solvents. Their photochemical properties such as singlet oxygen, and photodegradation quantum yields, and photophysical properties including fluorescence quantum yields and lifetimes were investigated in toluene. The fluorescence quenching behavior of the studied zinc(II) phthalocyanines by the addition of 1,4-benzoquinone were also described in toluene.

The novel axially bis[4-(4-pyridinyl)phenol] substituted silicon(IV) phthalocyanine (3) and its quaternized derivative (3Q) were designed and synthesized. These phthalocyanines were fully characterized by elemental analysis and different spectroscopic methods, such as FT-IR, UV–Vis, MALDI-TOF and 1H NMR. The photophysical and photochemical properties, such as electronic absorption, fluorescence emission, fluorescence lifetimes, singlet oxygen generation and photostability, of these phthalocyanines were investigated. These properties were examined in DMSO for the non-ionic phthalocyanine (3) and in both DMSO and aqueous solution for the ionic phthalocyanine (3Q). The addition of bis[4-(4-pyridinyl)phenol] groups as axial ligands showed an improvement of the photophysical and photochemical properties. In addition, a spectroscopic investigation of the binding behavior of the quaternized silicon(IV) phthalocyanine complex to bovine serum albumin (BSA) and DNA was also studied in this work.

A3B type unsymmetrical 8,11,15,18,22,25-hexadecyl-2,3-(9,10-dioctyl-6,7-dimethoxy-2,3-dioxytriptycene) (11) and 8,11,15,18,22,25-hexadecyl-2,3-(9,10-diundecyl-6,7-dimethoxy-2,3-dioxytriptycene) (12) zinc(II) phthalocyanines were synthesized for the first time. Their photophysical and photochemical properties were investigated as solutions in toluene and obtained values were compared with unsubstituted zinc(II) phthalocyanine for determination of substitution effect. Both newly synthesized phthalocyanines showed high singlet oxygen generation making them good candidates as photosensitizers for photocatalytic reactions.

New metal-free and zinc(II) phthalocyanines containing four triptycene moieties were synthesized and characterized by 1H NMR, mass, IR, electronic spectroscopies and elemental analysis as well. The steady-state absorption spectra of the investigated compounds exhibited the main absorption bands in the visible region, at around 700 nm. The fluorescence spectra and quantum yields were recorded by steady-state emission measurements. The powerful nanosecond laser flash photolysis technique was employed to record the transient absorption spectra of the long-lived triplet states of the investigated compounds. The singlet oxygen generation and photodegradation properties of the target phthalocyanines under light irradiation were also investigated in tetrahydrofuran solution.

Synthesis of a new symmetrical 1,4,8,11,15,18,22,25-octahexyloxy-2,3,9,10,16,17,23,24-octa-(3,5-dichlorophenyl)phthalocyaninato zinc(II), ZnPc, has been described and characterized by 1H NMR, 13C NMR, MS, UV–Vis, and IR spectrometry. The newly prepared ZnPc is soluble in organic solvents and is not aggregated in solution. The photophysical properties were studied by steady-state absorption and emission, cyclic voltammetry, and nanosecond transient absorption techniques. The prepared ZnPc absorbs and emits at longer wavelengths compared to that of reported phthalocyanine derivatives. The electron-donating properties of the ZnPc have been examined by mixing it with the electron-accepting dicyanoperylene-3,4,9,10-bis(dicarboximide), PDICN2. The recorded nanosecond transient spectra in the visible/near-IR region showed clearly the electron-transfer from the triplet-excited state of the ZnPc to PDICN2 with a rate of 3.40 × 108 M−1 s−1. Light absorption in a wide section of the solar spectrum, favorable redox properties, and the electron-transfer properties suggest usefulness of the ZnPc in light-energy harvesting and developing optoelectronic devices.

In this work, photochromic materials based on the dihydroindolizine (DHI) system were synthesized in multistep reactions using chemical and photochemical methods. Some of the synthesized photochromic dihydroindolizine derivatives were substituted on the fluorene (region A) and pyridazine (region C) moieties in order to provide the appropriate functionality for optimal tuning of the photochromic properties of the system. Irradiation of the photochromic DHIs with polychromatic light led to ring opened colored betaines, which underwent thermal 1,5-electrocyclization. The red to green colored betaines produced after UV irradiation returned back through 1,5-electrocyclization to the corresponding DHIs with different rate constants depending on the substituents in both fluorene and pyridazine regions. The kinetic measurements of the thermal 1,5-electrocyclization under different temperatures that ranged from −10 to 25 °C showed that the half-lives of the colored betaines fall in the second to hours domain. Interestingly, these materials showed a very good photochromic behavior not only in solution but also in the PMMA matrix. Irradiation of a slide prepared by the deep-coating method led to the formation of the colored betaine and the kinetics of the thermally reversible 1,5-electrocyclization and the AFM image of the film has been recorded. Indeed, the chemical and thermal stability of the investigated betaines in polymer (PMMA) will render such species useful for a plethora of new of applications.

The kinetics involved in the thermal degradation of an aryl azo dye-containing polynorbornene was investigated by using isothermal DSC data. The activation energy of the degradation was found to be temperature dependent with two different values of 140 ± 5 and 21 ± 2 kJ mol −1 , and the Avrami exponent was observed to increase from 2 to 4 in the temperature range 573–608 K. The degradation mechanism follows the Avrami–Erofeev mechanism for solid state reaction models and it changes from A2 toward A4 for the same temperature range.

NMR Studies on the reaction of triphenylphosphine with various amounts of triflic anhydride at 0 °C is described. The reagent structure resulting from mixing 1.3 equiv of Ph 3 P with Tf 2 O (1.0 mmol) has been established as an equilibrium mixture consisting mainly of triphenyl(trifluoromethylsulfonyloxy)phosphonium trifluoromethanesulfinate and the corresponding bis(triphenyl)oxodiphosphonium trifluoromethanesulfinate dimer. The electrophilic properties of the system have been exploited in the development of a mild method for converting aldoximes into nitriles. The dehydration occurs at 0 °C under very mild conditions by initial activation of the oxime oxygen, followed by treatment with a base and subsequent elimination of triphenylphosphine oxide. The substrate scope and functional group tolerance of this useful method are explored.

Novel symmetrical 1,4,8,11,15,18,22,25-octahexyloxy-2,3,9,10,16,17,23,24-octa-(3,5- dichlorophenoxy)phthalocyaninato zinc(II) was synthesized and characterized by 1H NMR, 13C NMR, MS, UV–Vis, XRD, and IR spectrometry. The synthesized ZnPc complex is soluble in various organic solvents such as CH2Cl2, THF, acetone, and ethyl acetate. This property helped to obtain thin films of the new ZnPc complex by spin coating method. The surface morphology of the thin films was investigated by atomic force microscopy, AFM, and showed that the molecules grow in stacks of rows. The spectrophotometric measurements of transmittance (T) and reflectance (R) spectra were carried out in the wavelength range 190–3000 nm.

The synthesis of novel, symmetrical, hexadecasubstituted phthalocyaninatozinc(II) bearing eight, fluorinated phenoxy groups in peripheral positions and eight, non-peripheral hexyloxy groups as well as their related unsymmetrical derivatives is described. The compounds were characterized by 1H NMR, GC–MS, UV–vis and IR. The synthesized ZnPc complexes possess excellent solubility in various organic solvents such as CH2Cl2, THF, acetone and ethyl acetate and do not readily aggregate in solution. The new complexes show interesting luminescence properties in different organic solvents.

Metal-free 1,4,8,11,15,18,22,25-octahexylphthalocyanine was prepared directly by the cyclotetramerization of 3,6-dihexylphthalonitrile using lithium butoxide in butanol. Thin films of the material were deposited on glass substrates by the thermal evaporation technique. The structure of the films was found to be in the α form, and showed a strong peak indicating preferential orientation. The surface morphology of the thin films was investigated by atomic force microscopy and showed that the molecules of 1,4,8,11,15,18,22,25-octahexylphthalocyanine grow in stacks of parallel rows. The spectrophotometric measurements of transmittance and reflectance were carried out in the wavelength range 190–3000 nm. The refractive index, n, and absorption index, k, were found to be independent of annealing at 373 K. The B band absorption occurred at 356 nm, and the Q band showed a doublet at 667 and 739 nm. Other optical parameters, such as absorption coefficient α and optical dielectric constant e, were determined.

The Vyazovkin model-free method were applied to study non-isothermal degradation of an aryl and hetaryl azo dye-containing polynorbornene using a differential scanning calorimetric (DSC) technique. The samples were heated in nitrogen, with heating rates in the range 5–50 K min −1 . The isoconversional method of Vyazovkin was used to determine the variation of the activation energy for degradation with temperature, E α ( T ). The values of E α ( T ) were found to be almost independent of temperature. The results of isoconversional methods used suggest that the transition follows a single-step kinetics reaction mechanism.