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Multi-Functional Monoamine Oxidase and Cholinesterase Inhibitors for the Treatment of Alzheimer’s Disease
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Ireen Denya, Sarel F. Malan, Jacques Joubert
The xanthone moiety has been used by a number of research groups as a promising scaffold in the design of MTDL with MAO and ChE inhibitory activities (Cruz et al., 2017; Luo et al., 2017; Pinto et al., 2005; Azevedo et al., 2012). Xanthones are a class of oxygenated heterocyclic compounds with a dibenzo-γ-pyrone scaffold (Pinto et al., 2005). In addition to natural xanthones, there are a large variety of xanthones of synthetic origin. Xanthones obtained by synthesis may hold simple substituents such as hydroxy, methoxy, methyl and carboxy moieties to more complex substitution patterns such as epoxide, azole, methylidenebutyrolactone, aminoalcohol, sulfamoyl, methylthiocarboxylic acid and dihydropyridine functional groups. Cruz et al. (2017) went on to summarise the SAR findings from numerous studies on xanthone scaffolds used to develop compounds with dual AChE and MAO inhibitory activities (Fig. 11.24).
PLGA-Based Nanoparticles for Cancer Therapy
Published in Jince Thomas, Sabu Thomas, Nandakumar Kalarikkal, Jiya Jose, Nanoparticles in Polymer Systems for Biomedical Applications, 2019
Xanthones are natural, semisynthetic, and heterocyclic compounds. Xanthone molecules having a range of substituents on the different carbons constitute a group of compounds with a broad spectrum of biological activities.74 These molecules inhibited the nitric oxide production from the macrophages and thus have strong inhibitory action on human cancer cell line expansion. Xanthone-loaded PLGA nanospheres have been prepared by solvent displacement techniques.92,74
Effects of spray-, oven-, and freeze drying on the physicochemical properties of poorly aqueous-soluble xanthone encapsulated by coacervation: A comparative study
Published in Drying Technology, 2022
Li Yoke Ho, Yau Yan Lim, Chin Ping Tan, Lee Fong Siow
According to Ho et al.,[36] under DSC scanning via open pans, evaporation behavior of water/volatile components between crystalline and amorphous powders are differentiated. Under open pan condition, the DSC scan of amorphous powders will result in a big endothermic hump over a wide range of temperature resulting from the evaporation of water/volatile molecules due to its porous structure.[36] The highly packed structure of crystalline powders restricts the evaporation of water/volatile molecules and result in one or a few sharp endothermic peaks. Xanthone has a sharp endothermic peak at around 177 °C, which is its melting point.[1] To reconfirm the XRD results (Figure 5), freeze-, oven-, and spray-dried coacervates were conducted under open pan condition for DSC to identify xanthone nature in the coacervates. DSC spectra of spray-dried α-CD powder exhibited an endothermic hump (40–170 °C) from water evaporation.[18] This was also reflected in the current study for xanthone coacervates for all the drying techniques (Figure 6). Oven and freeze-dried techniques showed xanthone endothermic peak, indicating xanthone crystalline nature but the spray-dried technique did not show any endothermic peak for xanthone. These results were supported by the XRD diffractogram in Figure 4.
Oil-in-water emulsion development for the encapsulation and sustained release of xanthone
Published in Journal of Dispersion Science and Technology, 2020
Nelida Yanina Martinez, Mario Sergio Moreno
Xanthone and xanthone derivatives are the main secondary metabolite of South East Asia Garcinia mangostana cultivated plant. It is commonly found in fruits of Garnicia mangostana and in roots of Hypericum species. Xanthones have antioxidant, antitumoral, antibacterial and antifungal properties.[1,2] The antioxidant properties are related to the structure of the molecule, where hydrogenated molecules are liable to H donation for free radical scavenging action. Owing to its natural origin, the use of xanthone avoids undesired side effects. Nevertheless, because of poor solubility of xanthone in water (0.1 mg/ml) and low bioavailability, its administration is limited. The encapsulation of xanthone into poly lactic-co-glycolic acid (PLGA) microemulsion has been proposed by previous authors to increase its bioavailability in pulmonary delivery.[3]