Synthesis and biological evaluation of isoflavone analogues from Dalbergia oliveri

Polyphenolic Profiling of Green Waste Determined by UPLC-HDMSE

Valorising green waste will greatly enhance and promote the sustainable management of this large volume resource. One potential way to achieve this is the extraction of high value human health promoting chemicals (e.g., polyphenols) from this material. Our primary aim was to identify the main polyphenols present in four contrasting green waste feedstocks, namely Smyrnium olusatrum, Urtica dioica, Allium ursinum and Ulex europaeus, using UPLC-HDMSE. Polyphenol-rich Camellia sinensis (green tea) was used as a reference material. Samples were extracted and analysed by UPLC-HDMSE, which was followed by data processing using Progenesis QI and EZ Info. A total of 77 high scoring polyphenolic compounds with reported benefits to human health were tentatively identified in the samples, with abundances varying across the plant types; A. ursinum was seen to be the least abundant in respect to the polyphenols identified, whereas U. europaeus was the most abundant. Important components with a diverse range of bioactivity, such as procyanidins, (−)-epigallocatechin, naringenin, eriodictyol and iso-liquiritigenin, were observed, plus a number of phytoestrogens such as daidzein, glycitin and genistein. This research provides a route to valorise green waste through the creation of nutritional supplements which may aid in the prevention of disease.

Screening of Phenolic Compounds in Australian Grown Berries by LC-ESI-QTOF-MS/MS and Determination of Their Antioxidant Potential

Berries are grown worldwide with the most consumed berries being blackberries (Rubus spp.), blueberries (Vaccinium corymbosum), red raspberries (Rubus idaeus) and strawberries (Fragaria spp.). Berries are either consumed fresh, frozen, or processed into wines, juices, and jams. In recent times, researchers have focused their attention on berries due to their abundance in phenolic compounds. The current study aimed to evaluate the phenolic content and their antioxidant potential followed by characterization and quantification using LC-ESI-QTOF-MS/MS and HPLC-PDA. Blueberries were highest in TPC (2.93 ± 0.07 mg GAE/gf.w.) and TFC (70.31 ± 1.21 µg QE/gf.w.), whereas the blackberries had the highest content in TTC (11.32 ± 0.13 mg CE/gf.w.). Blueberries had the highest radical scavenging capacities for the DPPH (1.69 ± 0.09 mg AAE/gf.w.), FRAP (367.43 ± 3.09 µg AAE/gf.w.), TAC (1.47 ± 0.20 mg AAE/gf.w.) and ABTS was highest in strawberries (3.67 ± 0.14 mg AAE/gf.w.). LC-ESI-QTOF-MS/MS study identified a total of 65 compounds including 42 compounds in strawberries, 30 compounds in raspberries, 28 compounds in blueberries and 21 compounds in blackberries. The HPLC-PDA quantification observed phenolic acid (p-hydroxybenzoic) and flavonoid (quercetin-3-rhamnoside) higher in blueberries compared to other berries. Our study showed the presence of phenolic acids and provides information to be utilized as an ingredient in food, pharmaceutical and nutraceutical industries.

Synthesis of Isoflavones by Tandem Demethylation and Ring-Opening/Cyclization of Methoxybenzoylbenzofurans

The unexpected conversion of benzoylbenzofurans into isoflavones through an intramolecular cascade that involves deprotection and ring-opening/cyclization is described. This was discovered in an investigation of the possible transformation of benzoylbenzofurans into coumaronochromones. This route affords isoflavones in two major steps from acetophenones and benzoquinones. The transformation was validated by synthesizing differently substituted isoflavone derivatives and further applied to a concise synthesis of a potential anticancer lead compound, glaziovianin A (1).

Proliferation Effects on Hair Growth of Compounds Isolated from the Bark of Dalbergia oliveri

One new isoflavane, 7,4′-dihydroxy-isoflavanquinone (1), together with ten known compounds (2–11) were isolated from the bark of Dalbergia oliveri Prain. The structures of compounds were determined on the basis of extensive spectroscopic methods, including 1D and 2D NMR and CD spectroscopic data. Using a cell proliferation assay, the isolated compounds were evaluated for their proliferation effects on hair growth. (3 R)-5’-Methoxyvestitol (2) and (6a R,11a R)-3,8-dihydroxy-9-methoxypterocarpan (10) significantly increased the proliferation of immortalized dermal papilla cells (iDPC).

Chemical constituents from Belamcanda chinensis and their inhibitory effects on nitric oxide production in RAW 264.7 macrophage cells

Belamcanda chinensis (L.) DC., which belongs to the family of Iridaceae, has been used as a folk medicine for the treatment of inflammation, asthma, tonsillitis, and many other throat disorders. Bioactivity-guided purification of the methylene chloride-soluble fraction of the rhizomes of B. chinensis based on the inhibition of nitric oxide production led to the identification of seventeen known compounds. Their structures were elucidated on the basis of extensive spectroscopic measurement such as NMR and ESI-MS. All of the isolated compounds were evaluated for their inhibitory effects on nitric oxide production in LPS-induced RAW 264.7 macrophage cells.

Synthesis and biological evaluation of 4-arylcoumarin analogues of combretastatins. Part 2

A series of A-ring variously methoxylated 4-(3-hydroxy-4-methoxyphenyl)coumarins related to combretastatin A-4 was prepared by cross-coupling reactions. Cytotoxicity studies indicated a potent activity against HBL100 cell line. Substitution patterns on A-ring had only a slight effect on antiproliferative activity. For most cytotoxic compounds, the activity as potential modulators of P-gp and BCRP efflux pumps was evaluated. The results show that compounds 2 and 7 were able to restore mitoxantrone accumulation (BCRP) at concentrations similar to that of cyclosporine A. Compound 7 was the most efficient to reverse P-gp activity. All compounds were found to potently inhibit in vitro microtubule formation via a substoichiometric mode of action for the most part. Compounds 1 and 2 were found to have an apparent affinity binding constant similar to that of combretastatin A-4, i.e., 1 × 10 (6) M(-1). The molecular modeling of coumarin derivatives was performed on the basis of the molecular structure of 7, as determined by single-crystal X-ray crystallography. The calculations suggested that the presence of a methoxy group out of the plane of the chromenone moiety is an important steric hindrance factor embedding the accessibility of those molecules inside the binding pocket on tubulin.

Chemical constituents of red Mexican propolis

Chemical investigation of a red-type Mexican propolis sample has led to the isolation of three new compounds, 1-(3',4'-dihydroxy-2'-methoxyphenyl)-3-(phenyl)propane (1), (Z)-1-(2'-methoxy-4',5'-dihydroxyphenyl)-2-(3-phenyl)propene (2) and 3-hydroxy-5,6-dimethoxyflavan (3), together with seven known flavanones, isoflavans, and pterocarpans. Structural determination, was accomplished by spectroscopic analysis, particularly 2D NMR and ESI-MS/MS techniques. The present study appears to be the first report on the occurrence of isoflavonoids in Mexican propolis. In addition, the presence of compounds with a 1,3-diarylpropane and 1,3-diarylpropene carbon skeleton were found for the first time in propolis. Isolated compounds 1-10 indicated the possible relation between red Mexican propolis and the genus Dalbergia.