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We report the first example of direct far-red triplet sensitized molecular photoswitching in a condensed phase wherein a liquid azobenzene derivative (Azo1) co-assembled within a liquid surfactant-protein film undergoes triplet sensitized Z-to-E photoswitching upon far-red/red light excitation in air. The role of triplet sensitization in photoswitching has been confirmed by quenching of sensitizer phosphorescence by Z-Azo1 and temperature-dependent photoswitching experiments. Herein, we demonstrate new biosustainable fabrication designs to address key challenges in solid-state photoswitching, effectively mitigating chromophore aggregation and requirement of high energy excitations by dispersing the photoswitch in the trapped liquid inside the solid framework and by shifting the action spectrum from blue-green light (450-560 nm) to the far-red/red light (740/640 nm) region., Pankaj Bharmoria acknowledges the Marie Skłodowska-Curie Actions—European Commission post-doctoral grant (NIRLAMS, Grant agreement ID: 844972) for research funding. Bo Albinsson acknowledges the Swedish Energy Agency and the Swedish Research Council (VR). Nobuo Kimizuka acknowledges JSPS KAKENHI Grant Number JP20H05676. Kasper Moth-Poulsen acknowledges funding from the European Research Council (ERC), the Göran Gustafson Foundation, the Swedish Energy Agency, and the Swedish Research Council (VR). The authors would like to thank Monika Shamsabadi and Lidiya M. Muhammad for proofreading this manuscript., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).

A combination of MS and computation on μ-nitrido bridged diiron complexes reveals H2O2 binding to the complex and generates an oxidant capable of oxidizing methane., Iron(iv)–oxo species have been identified as the active intermediates in key enzymatic processes, and their catalytic properties are strongly affected by the equatorial and axial ligands bound to the metal, but details of these effects are still unresolved. In our aim to create better and more efficient oxidants of H-atom abstraction reactions, we have investigated a unique heteroleptic diiron phthalocyanine complex. We propose a novel intramolecular approach to determine the structural features that govern the catalytic activity of iron(iv)–oxo sites. Heteroleptic μ-nitrido diiron phthalocyanine complexes having an unsubstituted phthalocyanine (Pc1) and a phthalocyanine ligand substituted with electron-withdrawing alkylsulfonyl groups (PcSO2R) were prepared and characterized. A reaction with terminal oxidants gives two isomeric iron(iv)–oxo and iron(iii)–hydroperoxo species with abundances dependent on the equatorial ligand. Cryospray ionization mass spectrometry (CSI-MS) characterized both hydroperoxo and diiron oxo species in the presence of H2O2. When m-CPBA was used as the oxidant, the formation of diiron oxo species (PcSO2R)FeNFe(Pc1) 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 O was also evidenced. Sufficient amounts of these transient species were trapped in the quadrupole region of the mass-spectrometer and underwent a CID-MS/MS fragmentation. Analyses of fragmentation patterns indicated a preferential formation of hydroperoxo and oxo moieties at more electron-rich iron sites of both heteroleptic μ-nitrido complexes. DFT calculations show that both isomers are close in energy. However, the analysis of the iron(iii)–hydroperoxo bond strength reveals major differences for the (Pc1)FeN(PcSO2R)FeIIIOOH system as compared to (PcSO2R)FeN(Pc1)FeIIIOOH system, and, hence binding of a terminal oxidant will be preferentially on more electron-rich sides. Subsequent kinetics studies showed that these oxidants are able to even oxidize methane to formic acid efficiently.

A monohydroxylated octasubstituted phthalocyanine, aimed at being used as a synthon for further conjugation, has been designed to offer rigorous comparison conditions to study the effect of the presence of an active moiety, compared to its non-functionalized symmetric analogs. After the validation of the concept using computational methods, the designed phthalocyanine was prepared and exhibited the expected suitable electronic absorption properties. Biotin conjugation was performed.

Photosensitized damage to liposome membranes was studied by using different dye-leakage assays based on fluorescence dequenching of a series of dyes upon their release from liposomes. Irradiation of liposomes with red light in the presence of a photosensitizer, trisulfonated aluminum phthalocyanine (AIPcS(3)), resulted in the pronounced leakage of carboxyfluorescein, hut rather weak leakage of sulforhodamine B and almost negligible leakage of calcein from the corresponding dye-loaded liposomes. The same series of selectivity of liposome leakage was obtained with chlorin c6 that appeared to be more potent than AlPcS3 in bringing about the photosensitized liposome leakage. Electrically neutral zinc phthalocyanine tetrasubstituted with a glycerol moiety (ZnPcGlyc(4)) was less effective than negatively charged AlPcS3 in provoking the light-induced liposome permeabilization. On the contrary, both ZnPcGlyc(4) and AlPcS3 were much more effective than chlorin c6 in sensitizing gramicidin channel inactivation in planar bilayer lipid membranes, dos showing that relative photodynamic efficacy of sensitizers can differ substantially for damaging different membrane targets. The photosensitized liposome permeabilization was apparently associated with oxidation of lipid double bonds by singlet oxygen as evidenced by the mandatory presence of unsaturated lipids in the membrane composition for the photosensitized liposome leakage to occur and the sensitivity of the latter to sodium azide. The fluorescence correlation spectroscopy measurements revealed marked permeability of photodynamically induced pores in liposome membranes for such photosensitizer as AlPcS3.

A complete set of platinum(II) solketal substituted phthalocyanines has been synthesized and characterized. To evaluate their potential as Type II photosensitizers for photodynamic therapy, comparative studies of their photophysical and photochemical properties with analogous zinc(II) series have been achieved: electronic absorption, fluorescence quantum yields, lifetimes, and fluorescence quenching by benzoquinone, as well as singlet oxygen generation and photodegradation. It appears that platinum(II) phthalocyanines are worth being used as Type II photosensitizers, as they exhibit good singlet oxygen generation and appropriate photodegradation. (C) 2010 Elsevier Ltd. All rights reserved.

Two series of amphiphilic carbohydrate-phthalocyanine conjugates have been prepared either by glycosylation or by copper-catalyzed click coupling. A common precursor, a hydroxylated phthalocyanine, was directly glycosylated or converted into an azido derivative before undergoing grafting of propargyl-carbohydrates by click reaction.

A complete series of solketal octasubstituted phthalocyanines have been synthesized, with peripheral (beta) or non-peripheral (alpha) substitution pattern. Their C-13 NMR and UV-vis properties are compared relatively to this substitution pattern or the nature of the central metal (Ni, Zn or H-2).

Non periferal okta sülfanil sübstitüsyona sahip ftalosiyaninlerler yakın kızıl ötesi bölgede absorpsiyon yapmakla birlikte bu moleküllerle ilgili yapılan çalışmalar azdır. Çalışmamızın bölümleri non periferal sübstitüsyon sonucu ortaya çıkan etki odağında şekillenmiştir.Birinci bölüm; 6 ile 16 karbon arasında zincire sahip sülfanil metalsiz ftalosiyanin serisi, olası sıvı kristal özelliklerini araştırmak üzere tasarlanmıştır. Karşılaştırma yapmak amacıyla periferal 12 karbonlu metalsiz ve nikel metalli ftalosiyanin hazırlanmıştır. Periferalle karşılaştırıldığında non periferal pozisyonun sıvı kristal düzenlenmeye olumsuz etkisi olduğu görülmüştür. Kristal yapısı olan tert-bütil sülfanil sübstitüe ftalosiyanin türevi non periferal sübstitüe bileşiklerde hacimli grubun spektroskopik etkilerini incelemek için hazırlanmıştır.İkinci bölüm; fotodinamik terapi için fotosensitizer olabilecek yakın infrared bölgede maksimum absorpsiyon yapan, fototerapik pencerede uyarılmaya uygun, non periferal okta sülfanil sübstitüsyon amaçlanmıştır. Daha iyi bir membran geçişi sağlamak için hücre içi alımını optimize etmek amacıyla uygun amfifilik özellikte asimetrik yapı tasarlanmıştır. Sentezdeki zorluklar karşısında alternatif yapılar da tasarlanmıştır. Adamantansülfanil, etilsülfanil ve hekzilsülfanil hidrofobik kısımlar ile 6-hidroksihekzilsülfanil kullanılarak hidroksillenmiş yapılar elde edilmiştir. Bu yapıların amfifilitesini arttırmak için polietilen glikol zincirini klik kimyası kullanılarak bağlanması düşünülmüştür fakat bu ftalosiyaninlerin farklı koşullarda ve pek çok adımda sentezlenebilmesi fonksiyonlandırmayı başarısız kılmıştır. Alternatif yapı klik kimyasının fonksiyonlandırılmasını detaylı bir şekilde araştırmak için tasarlanmıştır.Bu çalışmalar ftalosiyaninlerde non periferal okta sülfanil sübstitüsyon özellikleri ve kimyası hakkında bilgiler vermesi açısından önem taşımaktadır. The non-peripheral octa sulfanyl substitution pattern of phthalocyanines remained so far poorly investigated but highly promising due to the near-infra-red maximum absorption it induces. To get better knowledge on this substitution effect, these works focused on two main directions.In a first part, a complete series was designed to investigate the possible liquid crystalline properties of free (unmetalated) phthalocyanines with sulfanyl chains from 6 to 16 carbones. For comparison purposes, two nickel derivatives (C6 and C12) were prepared as well as their peripheral analogues. It appeared that the non-peripheral position had a negative effect on the liquid crystal assemblies, compared to peripheral analogues. Having prepared a tert-butyl sulfanyl derivative to get a crystalline compound, we got the opportunity to report on the effect of the macrocycle distorsion on the packing and spectroscopic properties of non-peripheral octa sulfanyl phthalocyanines.In a second part, these works aimed at exploiting the near-infrared maximum absorption of the non-peripheral octa sulfanyl substitution pattern to produce photosensitisers for photodynamic therapy, with an appropriate excitation in the phototherapeutic window. To get appropriate amphiphilicity in order to optimize the cellular uptake thanks to a better membrane crossing, asymmetric substitution pattern were designed. Synthetic difficulties prompted the design of alternative structures. Several hydroxylated structures with adamantanesulfanyl, ethylsulfanyl and hexylsulfanyl hydrophobic moieties facing 6-hydroxyhexylsylfanyl substituents were obtained. Further tailoring of the amphiphilicity was targeted with the introduction of polyethyleneglycol chains by click chemistry, but the functionalization of these phthalocyanines remained unsuccessful despite multiple attempts in various conditions. Alternative structure were designed to investigate in a detailed manner the functionalization requested to perform click chemistry.These works represent a good advancement of the knowledge of the chemistry and properties of the non-peripheral octa sulfanyl substitution pattern of phthalocyanines. 143