Chlorins: Natural Sources, Synthetic Developments and Main Applications

Oliveira, Kléber T. de; Momo, Patrícia B.; Assis, Francisco F. de; Ferreira, Marco A. B.; Brocksom, Timothy J.

doi:10.2174/15701794113106660085

Cited by 56 publications

(22 citation statements)

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“…Methylene blue, by its turn, is a low-cost phenothiazine derivative, well-soluble in water and ethanol, with a maximum absorption at 664 nm, a wavelength with good tissue penetration, which enables the application of MB to treat deeper lesions [18,19]. Finally, chlorin-e6 belongs to the class of chlorophyll derivatives, with its tetrapyrrole ring conferring it hydrophobic and hydrophilic (amphiphilic) features; it absorbs light in both 400 and 660 nm and produces high amounts of singlet oxygen, both in vitro and in vivo [20][21][22]. Structurally related to PDZ® (Photoditazine), Ce6 has been presenting better PDT activities due to its amphiphilicity and absence of dark toxicity [23] and is considered as a very promising candidate for systemic and non-systemic treatments.…”

Section: Introductionmentioning

confidence: 99%

Susceptibility of Enterococcus faecalis and Propionibacterium acnes to antimicrobial photodynamic therapy

Annunzio

Freitas

Blanco

et al. 2018

Journal of Photochemistry and Photobiology B: Biology

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Bacterial resistance to available antibiotics nowadays is a global threat leading researchers around the world to study new treatment modalities for infections. Antimicrobial photodynamic therapy (aPDT) has been considered an effective and promising therapeutic alternative in this scenario. Briefly, this therapy is based on the activation of a non-toxic photosensitizing agent, known as photosensitizer (PS), by light at a specific wavelength generating cytotoxic singlet oxygen and free radicals. Virtually all studies related to aPDT involve a huge screening to identify ideal PS concentration and light dose combinations, a laborious and time-consuming process that is hardly disclosed in the literature. Herein, we describe an antimicrobial Photodynamic Therapy (aPDT) study against Enterococcus faecalis and Propionibacterium acnes employing methylene blue, chlorin-e6 or curcumin as PS. Similarities and discrepancies between the two bacterial species were pointed out in an attempt to speed up and facilitate futures studies against those clinical relevant strains. Susceptibility tests were performed by the broth microdilution method. Our results demonstrate that aPDT mediated by the three above-mentioned PS was effective in eliminating both gram-positive bacteria, although P. acnes showed remarkably higher susceptibility to aPDT when compared to E. faecalis. PS uptake assays revealed that P. acnes is 80 times more efficient than E. faecalis in internalizing all three PS molecules. Our results evidence that the cell wall structure is not a limiting feature when predicting bacterial susceptibility to aPDT treatment.

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Section: Introductionmentioning

confidence: 99%

Susceptibility of Enterococcus faecalis and Propionibacterium acnes to antimicrobial photodynamic therapy

Annunzio

Freitas

Blanco

et al. 2018

Journal of Photochemistry and Photobiology B: Biology

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“…Two distinct methods for gaining access to chlorin macrocycles entail semisynthesis, where naturally occurring tetrapyrroles (e.g., heme, chlorophylls, bacteriochlorophylls) provide the initial starting material [1–4], and de novo synthesis, where the macrocycle is created from relatively simple, acyclic starting materials [5–7]. Semisynthesis has the advantage of abundant feedstocks but the disadvantage of a full complement of β-pyrrolic substituents, which can limit synthetic maneuverability.…”

Section: Introductionmentioning

confidence: 99%

Progress towards synthetic chlorins with graded polarity, conjugatable substituents, and wavelength tunability

Gauger

Muthukumaran

et al. 2015

J. Porphyrins Phthalocyanines

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Advances in chlorin synthetic chemistry now enable the de novo preparation of diverse chlorin-containing molecular architectures. Five distinct molecular designs have been explored here, including hydrophobic bioconjugatable (oxo)chlorins; a hydrophilic bioconjugatable chlorin; a trans-ethynyl/iodochlorin building block; a set of chlorins bearing electron-rich (methoxy, dimethylamino, methylthio) groups at the 3-position; and a set of ten 3,13-disubstituted chlorins chiefly bearing groups with extended π-moieties. Altogether 23 new chlorins (17 targets, 6 intermediates) have been prepared. The challenge associated with molecular designs that encompass the combination of “hydrophilic, bioconjugatable and wavelength-tunable” chiefly resides in the nature of the hydrophilic unit.

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“…Tetrapyrrolic derivatives like the heme group (Fe II complex of protoporphyrin IX) and chlorophylls are well known for their role in vital processes like respiration and photosynthesis, respectively 1. 2 However, interdisciplinary studies involving these types of macrocycles have pointed out the significant uses of their derivatives in catalysis, as sensors or biocides, new electronic materials, and in medicine 3. 4…”

Section: Introductionmentioning

confidence: 99%

Synthesis of New Chlorin e₆Trimethyl and Protoporphyrin IX Dimethyl Ester Derivatives and Their Photophysical and Electrochemical Characterizations

Menezes

Faustino

Oliveira

et al. 2014

Chemistry A European J

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In view of increasing demands for efficient photosensitizers for photodynamic therapy (PDT), we herein report the synthesis and photophysical characterizations of new chlorin e6 trimethyl ester and protoporphyrin IX dimethyl ester dyads as free bases and Zn(II) complexes. The synthesis of these molecules linked at the β-pyrrolic positions to pyrano[3,2-c]coumarin, pyrano[3,2-c]quinolinone, and pyrano[3,2-c]naphthoquinone moieties was performed by using the domino Knoevenagel hetero Diels-Alder reaction. The α-methylenechromanes, α-methylenequinoline, and ortho-quinone methides were generated in situ from a Knoevenagel reaction of 4-hydroxycoumarin, 4-hydroxy-6-methylcoumarin, 4-hydroxy-N-methylquinolinone, and 2-hydroxy-1,4-naphthoquinone, respectively, with paraformaldehyde in dioxane. All the dyads as free bases and as Zn(II) complexes were obtained in high yields. All new compounds were fully characterized by 1D and 2D NMR techniques, UV/Vis spectroscopy, and HRMS. Their photophysical properties were evaluated by measuring the fluorescence quantum yield, the singlet oxygen quantum yield by luminescence detection, and also the triplet lifetimes were correlated by flash photolysis and intersystem crossing (ISC) rates. The fluorescence lifetimes were measured by a time-correlated single photon count (TCSPC) method, fluorescence decay associated spectra (FDAS), and anisotropy measurements. Magnetic circular dichroism (MCD) and circular dichroism (CD) spectra were recorded for one Zn(II) complex in order to obtain information, respectively, on the electronic and conformational states, and interpretation of these spectra was enhanced by molecular orbital (MO) calculations. Electrochemical studies of the Zn(II) complexes were also carried out to gain insights into their behavior for such applications.

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Chlorins: Natural Sources, Synthetic Developments and Main Applications

Cited by 56 publications

References 0 publications

Susceptibility of Enterococcus faecalis and Propionibacterium acnes to antimicrobial photodynamic therapy

Susceptibility of Enterococcus faecalis and Propionibacterium acnes to antimicrobial photodynamic therapy

Progress towards synthetic chlorins with graded polarity, conjugatable substituents, and wavelength tunability

Synthesis of New Chlorin e₆Trimethyl and Protoporphyrin IX Dimethyl Ester Derivatives and Their Photophysical and Electrochemical Characterizations

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Chlorins: Natural Sources, Synthetic Developments and Main Applications

Cited by 56 publications

References 0 publications

Susceptibility of Enterococcus faecalis and Propionibacterium acnes to antimicrobial photodynamic therapy

Susceptibility of Enterococcus faecalis and Propionibacterium acnes to antimicrobial photodynamic therapy

Progress towards synthetic chlorins with graded polarity, conjugatable substituents, and wavelength tunability

Synthesis of New Chlorin e6Trimethyl and Protoporphyrin IX Dimethyl Ester Derivatives and Their Photophysical and Electrochemical Characterizations

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Product

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Synthesis of New Chlorin e₆Trimethyl and Protoporphyrin IX Dimethyl Ester Derivatives and Their Photophysical and Electrochemical Characterizations