Synthesis of Benzophenone Glucopyranosides from Phaleria macrocarpa and Related Benzophenone Glucopyranosides

Design, synthesis, in vitro, in silico, and SAR studies of flavone analogs towards anti-dengue activity

Flavone has recently been proved as a promising scaffold for the development of a novel drug against dengue fever, one of the major health threats globally. However, the structure-activity relationship study of flavones on the anti-dengue activity remains mostly limited to the natural-occuring analogs. Herein, 27 flavone analogs were successfully synthesized, of which 5 analogs (5e, 5h, 5o, 5q, and 5r) were novel. In total, 33 analogs bearing a diverse range of substituents were evaluated for their efficacy against DENV2-infected LLC/MK2 cells. The introduction of electron-withdrawing groups on ring B such as Br (5m) or NO₂ (5n and 5q) enhanced the activity significantly. In particular, the tri-ester 5d and di-ester 5e exhibited low toxicity against normal cell, and exceptional DENV2 inhibition with the EC₅₀ as low as 70 and 68 nM, respectively, which is over 300-fold more active compared to the original baicalein reference. The viral targets for these potent flavone analogs were predicted to be NS5 MTase and NS5 RdRp, as suggested by the likelihood ratios from the molecular docking study. The great binding interaction energy of 8-bromobaicalein (5f) confirms the anti-dengue activity at atomistic level. The physicochemical property of all the synthetic flavone analogs in this study were predicted to be within the acceptable range. Moreover, the QSAR model showed the strong correlation between the anti-dengue activity and the selected molecular descriptors. This study emphasizes the great potential of flavone as a core structure for further development as a novel anti-dengue agent in the future.

Biochemical Constituents of Phaleria macrocarpa (Leaf) Methanolic Extract Inhibit ROS Production in SH-SY5Y Cells Model

Background. Reactive oxygen species generation in mammalian cells profoundly affects several critical cellular functions, and the lack of efficient cellular detoxification mechanisms which remove these radicals may lead to several human diseases. Several studies show that ROS is incriminated as destructive agents in the context of the nervous system especially with advance in age leading to neurodegeneration. Current treatments of this disease are not effective and result in several side effects. Thus, the search for alternative medicines is in high demand. Therefore, the aim of this study is to evaluate the reactive oxygen inhibitory effect of Phaleria macrocarpa 80% (leaf) extract. Methods. The leaf was extracted with 80% methanol. Cytotoxicity studies were carried out using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and ROS inhibitory activities were evaluated using dichlorofluorescein diacetate (DCF-DA) assay in the SH-SY5Y cells model. Results. The result revealed ROS inhibitory activities of the crude extract with highly significant differences at $p<0.001$ between the group that were treated with crude extract only, the group treated with crude extract and exposed to H2O2, and the group exposed to H2O2 only as well as the group that were maintained in complete media. Bioactive compounds show the presence of vitexin and isovitexin following the HPLC method. Conclusion. High antioxidant activities and low toxicity effect of this crude revealed its high benefit to be used as natural medicine/supplements.

Glycosides of ursane-type triterpenoid, benzophenone, and iridoid from Vangueria agrestis (Fadogia agrestis) and their anti-infective activities

Four ursane-type triterpenoid glycosides (1-4), two benzophenone glycosides (5 and 6), and one iridoid glucoside (7) were isolated and characterized from the dried roots of Vangueria agrestis. Compounds 1 (3-O-[α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranosyl]pomolic acid 28-O-β-D-glucopyranosyl ester) and 5 (2-O-[β-D-apiofuranosyl-(1→6)-β-D-glucopyranosyl]-6,4'-dihydroxy-4-methoxy benzophenone) were found to be new metabolites. The identity of all compounds has been accomplished, primarily, based on 1 D and 2 D NMR and HRESMS analysis. Compounds 6 and 2, showed inhibitory effect against Trypanosoma brucei with IC₅₀ 22.3 µM for 6 and IC₅₀ 11.1 µM, IC₉₀ 12.3 µM for 2.

Benzophenones from Mango Leaves Exhibit α-Glucosidase and NO Inhibitory Activities

Mango (Mangifera indica L.) is a succulent tropical fruit. Bioactive phytochemical investigation has been carried out to the leaves of mango. Three new benzophenone glycosides, along with 14 known compounds, were purified and identified. The novel benzophenones were elucidated to be 2,4,4',6-tetrahydroxy-3'-methoxybenzophenone-3-C-β-d-glucopyranoside (1), 4,4',6-trihydroxybenzophenone-2-O-α-l-arabinofuranoside (7), and 4',6-dihydroxy-4-methoxybenzophenone-2-O-(2″),3-C-(1″)-1″-desoxy-α-l-fructofuranoside (11). The α-glucosidase inhibitory, NO production inhibitory, and antioxidant activities were assessed for the purified benzophenones and triterpenoids. Some benzophenones showed moderate α-glucosidase and NO inhibitory activities. The IC₅₀ value of the α-glucosidase inhibitory of isolated compounds 1, 13, and 14 were 284.93 ± 20.29, 239.60 ± 25.00, and 297.37 ± 8.12 μM, respectively. Most compounds showed moderate effects to reduce the NO content in 50 and 100 μM. The above results of bioactivity powerfully demonstrated the phytochemicals from mango, especially benzophenones, probably partially rational for its antidiabetes and anti-inflammatory.

Antioxidants, phytochemicals, and cytotoxicity studies on Phaleria macrocarpa (Scheff.) Boerl seeds

In recent years, the utilization of certain medicinal plants as therapeutic agents has drastically increased. Phaleria macrocarpa (Scheff.) Boerl is frequently used in traditional medicine. The present investigation was undertaken with the purpose of developing pharmacopoeial standards for this species. Nutritional values such as ash, fiber, protein, fat, and carbohydrate contents were investigated, and phytochemical screenings with different reagents showed the presence of flavonoids, glycosides, saponin glycosides, phenolic compounds, steroids, tannins, and terpenoids. Our results also revealed that the water fraction had the highest antioxidant activity compared to the methanol extract and other fractions. The methanol and the fractionated extracts (hexane, chloroform, ethyl acetate, and water) of P. macrocarpa seeds were also investigated for their cytotoxic effects on selected human cancer cells lines (MCF-7, HT-29, MDA-MB231, Ca Ski, and SKOV-3) and a normal human fibroblast lung cell line (MRC-5). Information from this study can be applied for future pharmacological and therapeutic evaluations of the species, and may assist in the standardization for quality, purity, and sample identification. To the best of our knowledge, this is the first report on the phytochemical screening and cytotoxic effect of the crude and fractionated extracts of P. macrocarpa seeds on selected cells lines.

Phytochemistry and medicinal properties of Phaleria macrocarpa (Scheff.) Boerl. extracts

Phaleria macrocarpa, commonly known as Mahkota dewa is a medicinal plant that is indigenous to Indonesia and Malaysia. Extracts of P. macrocarpa have been used since years in traditional medicine that are evaluated scientifically as well. The extracts are reported for a number of valuable medicinal properties such as anti-cancer, anti-diabetic, anti-hyperlipidemic, anti-inflammatory, anti-bacterial, anti-fungal, anti-oxidant and vasorelaxant effect. The constituents isolated from different parts of P. macrocarpa include Phalerin, gallic acid, Icaricide C, magniferin, mahkoside A, dodecanoic acid, palmitic acid, des-acetylflavicordin-A, flavicordin-A, flavicordin-D, flavicordin-A glucoside, ethyl stearate, lignans, alkaloids andsaponins. The present review is an up-to-date summary of occurrence, botanical description, ethnopharmacology, bioactivity and toxicological studies related to P. macrocarpa.

Phytochemistry and medicinal properties of Phaleria macrocarpa (Scheff.) Boerl. extracts

Phaleria macrocarpa, commonly known as Mahkota dewa is a medicinal plant that is indigenous to Indonesia and Malaysia. Extracts of P. macrocarpa have been used since years in traditional medicine that are evaluated scientifically as well. The extracts are reported for a number of valuable medicinal properties such as anti-cancer, anti-diabetic, anti-hyperlipidemic, anti-inflammatory, anti-bacterial, anti-fungal, anti-oxidant and vasorelaxant effect. The constituents isolated from different parts of P. macrocarpa include Phalerin, gallic acid, Icaricide C, magniferin, mahkoside A, dodecanoic acid, palmitic acid, des-acetylflavicordin-A, flavicordin-A, flavicordin-D, flavicordin-A glucoside, ethyl stearate, lignans, alkaloids andsaponins. The present review is an up-to-date summary of occurrence, botanical description, ethnopharmacology, bioactivity and toxicological studies related to P. macrocarpa.