Organocatalyzed Asymmetric Vinylogous Addition of Oxazole-2(3H)-thiones to α,β-Unsaturated Ketones: An Additive-Free Approach for Diversification of Heterocyclic Scaffold.

A straightforward organocatalyzed asymmetric addition of oxazole-2(3H)-thiones to α,β-unsaturated ketones is described. This additive-free Michael reaction in the presence of chiral cinchonine-derived primary amines as catalysts has proven to be highly effective for a wide range of cyclic and acyclic enones, leading to the Michael adducts in very good yields and excellent enantioselectivities. The absolute configuration (R) of compound 5j was unambiguously assigned by X-ray diffraction analysis.

Mitochondria-Targeted Photodynamic Therapy with a Galactodendritic Chlorin to Enhance Cell Death in Resistant Bladder Cancer Cells.

Here, we report the rational design of a new third-generation photosensitizer (PS), a chlorin conjugated with galactodendritic units, ChlGal, to improve the effectiveness of bladder cancer treatment. ChlGal shows better photochemical and photophysical properties than a recently reported homologous porphyrin, PorGal. In addition to inheriting excellent photostability, the ability to generate singlet oxygen, and the ability to interact with the proteins galectin-1 and human serum albumin (HSA), ChlGal exhibits high absorption in the red region of the electromagnetic spectrum.

The role of galectin-1 in in vitro and in vivo photodynamic therapy with a galactodendritic porphyrin.

Conventional photodynamic agents used in clinic are porphyrin-based photosensitizers. However, they have low tumour selectivity, which may induce unwanted side-effects and damage to healthy tissues. In this study, we used a porphyrin with dendritic units of galactose (PorGal) developed by us, which can target the galactose-binding protein, galectin-1, known to be overexpressed in many tumour tissues.

Galactodendritic porphyrinic conjugates as new biomimetic catalysts for oxidation reactions.

This work employed [5,10,15,20-tetrakis(pentafluorophenyl)porphyrin] ([H2(TPPF20)], H2P1) as the platform to prepare a tetrasubstituted galactodendritic conjugate porphyrin (H2P3). After metalation with excess copper(II) acetate, H2P3 afforded a new solid porphyrin material, Cu4CuP3S. This work also assessed the ability of the copper(II) complex (CuP3) of H2P3 to coordinate with zinc(II) acetate, to yield the new material Zn4CuP3S.

Identification and evaluation of improved 4'-O-(alkyl) 4,5-disubstituted 2-deoxystreptamines as next-generation aminoglycoside antibiotics.

Unlabelled: The emerging epidemic of drug resistance places the development of efficacious and safe antibiotics in the spotlight of current research. Here, we report the design of next-generation aminoglycosides. Discovery efforts were driven by rational synthesis focusing on 4' alkylations of the aminoglycoside paromomycin, with the goal to alleviate the most severe and disabling side effect of aminoglycosides-irreversible hearing loss.

Galactodendritic phthalocyanine targets carbohydrate-binding proteins enhancing photodynamic therapy.

Photosensitizers (PSs) are of crucial importance in the effectiveness of photodynamic therapy (PDT) for cancer. Due to their high reactive oxygen species production and strong absorption in the wavelength range between 650 and 850 nm, where tissue light penetration is rather high, phthalocyanines (Pcs) have been studied as PSs of excellence. In this work, we report the evaluation of a phthalocyanine surrounded by a carbohydrate shell of sixteen galactose units distributed in a dendritic manner (PcGal16) as a new and efficient third generation PSs for PDT against two bladder cancer cell lines, HT-1376 and UM-UC-3.

Porphyrin conjugated with serum albumins and monoclonal antibodies boosts efficiency in targeted destruction of human bladder cancer cells.

The synthesis of a novel PS conjugated with bovine and human serum albumin (BSA and HSA) and a monoclonal antibody anti-CD104 is reported, as well as their biological potential against the human bladder cancer cell line UM-UC-3. No photodynamic effect was detected when the non-conjugated porphyrin was used. Yet, when it was coupled covalently with the mAb anti-CD104, BSA and HSA, the resulting photosensitizer conjugates demonstrated high efficacy in destroying the cancer cells, the mAb anti-CD104 efficacy overruling the albumins.

Cationic galactoporphyrin photosensitisers against UV-B resistant bacteria: oxidation of lipids and proteins by 1(O2).

Antimicrobial photodynamic inactivation is becoming a promising alternative to control microbial pathogens. The combination of positively charged groups and carbohydrate moieties with porphyrin derivatives results in increased cell recognition and water solubility, which improves cell membrane penetration. However, the nature of the oxidative damage and the cellular targets of photodamage are still not clearly identified.

Spirocyclic nucleosides in medicinal chemistry: an overview.

This review describes some spiro- and pseudospironucleoside derivatives as well as their biological and pharmacological applications.

Porphyrin and phthalocyanine glycodendritic conjugates: synthesis, photophysical and photochemical properties.

Synthesis of water soluble porphyrin and phthalocyanine derivatives with, respectively, eight and sixteen galactose units has been carried out. The combined preliminary photophysical and photochemical features of the new products suggest that they might be promising photodynamic therapeutic agents.

1,1'-[(5-Hy-droxy-methyl-1,3-phenyl-ene)bis-(methyl-ene)]dipyridin-4(1H)-one monohydrate.

The asymmetric unit of the title compound, C(19)H(18)N(2)O(3), comprises a whole organic dipyridinone mol-ecule plus a water mol-ecule of crystallization. The planes of the pyridinone rings are approximately perpendicular with the plane of the central aromatic ring [dihedral angles = 80.68 (8) and 83.

Oxazolinethiones and oxazolidinethiones for the first copper-catalyzed desulfurative cross-coupling reaction and first sonogashira applications.

Cyclic thionocarbamates, namely chiral oxazolidinethiones (OZT) and aromatic oxazolinethiones (OXT), were involved, for the first time, in Sonogashira cross-coupling. A cooperative effect of two different copper (I) species-CuI and CuTC-accounts for this new copper-catalyzed desulfurative carbon-carbon cross-coupling reaction. This cooperative reactivity could also be extended to other copper (I) catalysts.