Synthesis and Antiproliferative Effect of 3,4,5-Trimethoxylated Chalcones on Colorectal and Prostatic Cancer Cells.

In the context of designing innovative anticancer agents, the synthesis of a series of chalcones bearing a 3,4,5-trimethoxylated A ring and a variety of B rings, including phenols and original heterocycles such as chromones, was conducted. For this end, Claisen-Schmidt condensation was performed in basic or acidic conditions between the common starting material 3,4,5-trimethoxyacetophenone and appropriate aldehydes; this allowed the recovery of fifteen chalcones in moderate-good yields. The synthesized compounds were screened for their antiproliferative activity against colorectal and prostatic cancer cells, using a colorimetric MTT assay.

An expeditive and green chemo-enzymatic route to diester sinapoyl-l-malate analogues: sustainable bioinspired and biosourced UV filters and molecular heaters.

Sinapoyl malate, naturally present in plants, has proved to be an exceptional UV filter and molecular heater for plants. Although there are nowadays industrially relevant sustainable synthetic routes to sinapoyl malate, its incorporation into certain cosmetic formulations, as well as its adsorption on plant leaves, is limited by its hydrophilicity. To overcome these obstacles, it is important to find a way to effectively control the hydrophilic-lipophilic balance of sinapoyl malate to make it readily compatible with the cosmetic formulations and stick on the waxy cuticle of leaves.

Direct structural observation of ultrafast photoisomerization dynamics in sinapate esters.

Sinapate esters have been extensively studied for their potential application in 'nature-inspired' photoprotection. There is general consensus that the relaxation mechanism of sinapate esters following photoexcitation with ultraviolet radiation is mediated by geometric isomerization. This has been largely inferred through indirect studies involving transient electronic absorption spectroscopy in conjunction with steady-state spectroscopies.

Insight into the Photodynamics of Photostabilizer Molecules.

Solar exposure of avobenzone, one of the most widely used commercial UVA filters on the market, is known to cause significant degradation. This finding has fueled research into developing photostabilizer molecules. In an effort to provide insight into their stand-alone photoprotection properties, the excited state dynamics of the photostabilizer, 3-(3,4,5-trimethoxybenzylidene) pentane-2,4-dione (TMBP), and its phenolic derivative, 3-(4-hydroxy-3,5-dimethoxybenzylidene) pentane-2,4-dione (DMBP), were studied with ultrafast transient absorption spectroscopy.

From Biomass-Derived -Hydroxycinnamic Acids to Novel Sustainable and Non-Toxic Phenolics-Based UV-Filters: A Multidisciplinary Journey.

Although organic UV-filters are extensively used in cosmetics to protect consumers from the deleterious effects of solar UV radiation-exposure, they suffer from some major drawbacks such as their fossil origin and their toxicity to both humans and the environment. Thus, finding sustainable and non-toxic UV-filters is becoming a topic of great interest for the cosmetic industry. A few years ago, sinapoyl malate was shown to be a powerful naturally occurring UV-filter.

Towards developing novel and sustainable molecular light-to-heat converters.

Light-to-heat conversion materials generate great interest due to their widespread applications, notable exemplars being solar energy harvesting and photoprotection. Another more recently identified potential application for such materials is in molecular heaters for agriculture, whose function is to protect crops from extreme cold weather and extend both the growing season and the geographic areas capable of supporting growth, all of which could help reduce food security challenges. To address this demand, a new series of phenolic-based barbituric absorbers of ultraviolet (UV) radiation has been designed and synthesised in a sustainable manner.

Synthesis and biological evaluation of chalcone-polyamine conjugates as novel vectorized agents in colorectal and prostate cancer chemotherapy.

The aim of this study was to synthesize chalcone-polyamine conjugates in order to enhance bioavailability and selectivity of chalcone core towards cancer cells, using polyamine-based vectors. Indeed, it is well-known that polyamine transport system is upregulated in tumor cells. 3',4,4',5'-tetramethoxychalcone was selected as parent chalcone since it was found to be an efficient anti-proliferative agent on various cancer cells.

New Generation UV-A Filters: Understanding Their Photodynamics on a Human Skin Mimic.

The sparsity of efficient commercial ultraviolet-A (UV-A) filters is a major challenge toward developing effective broadband sunscreens with minimal human- and eco-toxicity. To combat this, we have designed a new class of Meldrum-based phenolic UV-A filters. We explore the ultrafast photodynamics of coumaryl Meldrum, CMe, and sinapyl Meldrum (SMe), both in an industry-standard emollient and on a synthetic skin mimic, using femtosecond transient electronic and vibrational absorption spectroscopies and computational simulations.

Sustainable Synthesis of -Hydroxycinnamic Diacids through Proline-Mediated Knoevenagel Condensation in Ethanol: An Access to Potent Phenolic UV Filters and Radical Scavengers.

-Hydroxycinnamic diacids are reaction intermediates of the classical Knoevenagel-Doebner condensation between malonic acid and benzaldehydes. As they are generally obtained in low yields, they remain relatively under-studied and under-exploited. Herein, we developed and optimized a sustainable synthetic procedure allowing the production of these compounds in good to high yields (60-80%) using proline as the catalyst and ethanol as the solvent.

Enhancement of hydrosolubility and in vitro antiproliferative properties of chalcones following encapsulation into β-cyclodextrin/cellulose-nanocrystal complexes.

This paper describes the preparation of two chalcone/β-cyclodextrin/cellulose-nanocrystals complexes and the study of their antiproliferative activities against two colorectal and two prostatic cancer cell lines. The aim of this work was to enhance hydrosolubility of chalcones thanks to the hydrophilic character of cellulose nanocrystals. These latter were linked, through ionic interactions, to a cationic derivative of β-cyclodextrins whose lipophilic cavity allowed the encapsulation of hydrophobic chalcones: 3-hydroxy-3',4,4',5'-tetramethoxychalcone (1) and 3',4,4',5'-tetramethoxychalcone (2).

Determination of eumelanin and pheomelanin in melanomas using solid-phase extraction and high performance liquid chromatography-diode array detection (HPLC-DAD) analysis.

Determination of eumelanin and pheomelanin in melanomas that exhibit different pigmentation was carried using a solid-phase extraction (SPE) preparation method based on weak anion exchange chemistry. This extraction significantly enhanced the chromatographic profile obtained by reverse phase high performance liquid chromatography-diode array detection (RP-HPLC-DAD). The SPE method was developed using aqueous standards of melanin markers: thiazole-2,4,5-tricarboxylic acid (TTCA), thiazole-4,5-dicarboxylic acid (TDCA), pyrrole-2,3-dicarboxylic acid (PDCA) and pyrrole-2,3,5-tricarboxylic acid (PTCA) and non-pigmented cell lines spiked with those markers.

Design and multi-step synthesis of chalcone-polyamine conjugates as potent antiproliferative agents.

The aim of this study is to synthesize chalcone-polyamine conjugates in order to enhance bioavailability and selectivity of chalcone core towards cancer cells, using polyamine-based vectors. 3-hydroxy-3',4,4',5'-tetramethoxychalcone (1) and 3',4,4',5'-tetramethoxychalcone (2) were selected as parent chalcones since they were found to be efficient anti-proliferative agents on various cancer cells. A series of ten chalcone-polyamine conjugates was obtained by reacting carboxychalcones with different polyamine tails.

Resistance to 3-HTMC-Induced Apoptosis Through Activation of PI3K/Akt, MEK/ERK, and p38/COX-2/PGE Pathways in Human HT-29 and HCT116 Colorectal Cancer Cells.

Increasing incidence and mortality of colorectal cancer brings the necessity to uncover new possibilities in its prevention and treatment. Chalcones have been identified as interesting compounds having chemopreventive and antitumor properties. In this study, we investigated the effects of the synthetic chalcone derivative 3-hydroxy-3',4,4',5'-tetra-methoxy-chalcone (3-HTMC) on proliferation, cell cycle distribution, apoptosis, and its mechanism of action in human colorectal HT-29 (COX-2 sufficient) and HCT116 (COX-2 deficient) cancer cells.