Inhibition of UVA Damage on Human Skin Dermis Fibroblasts by the Isoflavonoid Intermediate Deoxybenzoin-3A

Synthesis of deoxybenzoins from β-alkoxy styrenes and arylboronic acids via palladium-catalyzed regioselective Heck-arylation reactions

Palladium-catalyzed synthesis of deoxybenzoin derivatives from styryl ethers and arylboronic acids is reported. The reaction proceeds under mild conditions in the presence of TEMPO and provides the desired products in good to excellent yields. Simple operation, broad substrate scope, and functional group tolerance are the salient features of the developed methodology.

Protective Effects of Pear Extract on Skin from In Vitro and In Vivo UVA-Induced Damage

The ancient Chinese medical book "Compendium of Materia Medica" records that pears can relieve symptoms of respiratory-related diseases. Previous research has shown that pear Pyrus Pyrifolia (Burm.f.) Nakai has antioxidant and anti-inflammatory properties. However, the anti-inflammatory, antioxidant, and anti-photoaging protective effects of Pyrus pyrifolia (Burm.f.) Nakai seed components have not been studied. Ultraviolet light (UV) causes skin inflammation, damages the skin barrier, and is an important cause of skin photoaging. Therefore, UV light with a wavelength of 365 nm was used to irradiate HaCaT and mice. Western blot, real-time quantitative polymerase chain reaction, and fluorescence imaging system were used to explore its anti-UVA mechanism. Dialysis membrane and nuclear magnetic resonance were used for the chemical constituent analysis of pear seed water extract (PSWE). We found that PSWE can significantly reduce UVA-induced skin cell death and mitogen-activated protein kinase phosphorylation and can inhibit the mRNA expression of UVA-induced cytokines (including IL-1β, IL-6, and TNF-α). In addition, PSWE can also reduce the generation of oxidative stress within skin cells. In vivo experimental studies found that PSWE pretreatment effectively reduced transepidermal water loss, inflammation, redness, and dryness in hairless mice. The molecular weight of the active part of pear water extract is approximately 384. Based on the above results, we first found that pear seeds can effectively inhibit oxidative stress and damage caused by UVA. It is a natural extract with antioxidant properties and anti-aging activity that protects skin cells and strengthens the skin barrier.

Inhibitory Effects of B-, C-, and E-Ring-Truncated Deguelin Derivatives Against A549, HCT116, and MCF-7 Cancer Cells

Deguelin has been extensively studied for its anticancer properties; however, its clinical application has been hindered by concerns about in vivo toxicity. Structural modifications of deguelin including ring truncation have been explored to enhance its pharmacological properties. In this study, the design and straightforward synthesis of a series of B, C, and E (BCE)-ring-truncated deguelin analogues with deoxybenzoin backbone were described. The structure-activity relationships (SARs) were established by evaluation of their inhibitory activities against three cancer cell lines, A549 (adenocarcinomic human alveolar basal epithelial cells), HCT116 (human colorectal cancer cells), and MCF-7 (breast cancer cells). Six derivatives demonstrated significant and selective inhibitory activities. The ketone derivative 3a showed potency against A549 (IC50 = 6.62 μM) while the oxime analogue 6a and D-ring-benzylated ketone analogue 8d exhibited activity against HCT116 (IC50 = 3.43 and 6.96 μM, respectively). Moreover, the D-ring alkylated derivatives 8c and 8e-f were active against MCF-7 cells (IC50 < 10 μM). The potential suitability of the BCE-ring-truncated deguelin derivatives for drug development was further supported by the favorable in silico prediction of their physicochemical properties, druglikeness, and toxicity. This study could provide valuable insights for the further development of novel anticancer agents.

Na2S-Mediated One-Pot Selective Deoxygenation of α-Hydroxyl Carbonyl Compounds including Natural Products

A practical method for the deoxygenation of α-hydroxyl carbonyl compounds under mild reaction conditions is reported here. The use of cheap and easy-to-handle Na₂S·9H₂O as the reductant in the presence of PPh₃ and N-chlorosuccinimide (NCS) enables the selective dehydroxylation of α-hydroxyl carbonyl compounds, including ketones, esters, amides, imides and nitrile groups. The synthetic utility is demonstrated by the late-stage deoxygenation of bioactive molecule and complex natural products.