Iodine catalyzes C-glycosidation of d-glucal with silylacetylene

A convenient method for C-glycosidation (alkynylation) with various silylacetylenes to d-glucal by iodine molecule via iodo-oxonium intermediates provided exclusively the α-acetylene glycoside products. Eleven successful examples are shown under this condition.     

A Comparison of the Nutritional and Biochemical Quality of Date Palm Fruits Obtained Using Different Planting Techniques

Date palm fruit (Phoenix dactylifera L.) is commonly consumed around the world and has recently become an economical crop in Eastern Thailand, especially the Barhi cultivar that can be consumed as fresh fruit. To maintain genetic qualities, date palm is populated through cell culture. This leads to high production costs, while access to this technique is limited. Increasing date palm population by simple seed planting is currently of interest as an alternative for local farmers. Nevertheless, information on nutritive values, bioactive compounds, and health-promoting bioactivities of seed originating from date palm fruit is unavailable. Effects of different planting origins (cell culture origin (CO) and seed origin (SO)) of date palm fruits at the Khalal stage of Barhi cultivar were investigated for nutritive values, bioactive compounds, and in vitro health-promoting properties via key enzyme inhibitions against obesity (lipase), diabetes (α-amylase, α-glucosidase, and dipeptidyl peptidase-IV), Alzheimer’s disease (cholinesterases and β-secretase), and hypertension (angiotensin-converting enzyme). Waste seeds as a by-product from date palm production were also examined regarding these properties to increase seed marketing opportunities for future food applications and other health-related products. CO and SO exhibited insignificant differences in energy, fat, and carbohydrate contents. SO had higher protein, dietary fiber, vitamin A, vitamin E, and calcium contents than CO, while CO contained higher contents of fructose, glucose and maltose. Higher phenolic contents in SO led to greater enzyme inhibitory activities than CO. Interestingly, seeds of date palm fruits mostly contained higher nutritive values than the flesh. No carotenoids were detected in seeds but higher phenolic contents resulted in greater enzyme inhibitory activities than recorded for fruit flesh. Results suggest that appropriate planting of date palm can support the development of novel date palm fruit products, leading to expansion of economic opportunities and investment in date palm fruit agriculture.     

The Crystal Structure of a Homodimeric Pseudomonas Glyoxalase I Enzyme Reveals Asymmetric Metallation Commensurate with Half‐of‐Sites Activity

The Zn inactive class of glyoxalase I (Glo1) metalloenzymes are typically homodimeric with two metal‐dependent active sites. While the two active sites share identical amino acid composition, this class of enzyme is optimally active with only one metal per homodimer. We have determined the X‐ray crystal structure of GloA2, a Zn inactive Glo1 enzyme from Pseudomonas aeruginosa. The presented structures exhibit an unprecedented metal‐binding arrangement consistent with half‐of‐sites activity: one active site contains a single activating Ni²⁺ ion, whereas the other contains two inactivating Zn²⁺ ions. Enzymological experiments prompted by the binuclear Zn²⁺ site identified a novel catalytic property of GloA2. The enzyme can function as a Zn²⁺/Co²⁺‐dependent hydrolase, in addition to its previously determined glyoxalase I activity. The presented findings demonstrate that GloA2 can accommodate two distinct metal‐binding arrangements simultaneously, each of which catalyzes a different reaction.     

One-pot solvent-free synthesis of triaryl- and triheteroarylmethanes by Bi(OTf)3-catalyzed Friedel-Crafts reaction of arenes/heteroarenes with trialkyl orthoformates

A convenient, practical and highly efficient one-pot method has been developed for the synthesis of triaryl- and triheteroarylmethane derivatives by Bi(OTf)₃-catalyzed Friedel-Crafts alkylation of trialkyl orthoformates in combination with a wide variety of arenes/heteroarenes at room temperature under solvent-free conditions and in an air atmosphere. The methodology offers an operational simplicity, high atom economy and environmentally benign procedure. Furthermore, selected compound 3k showed promising anti-inflammatory activity with inhibition nitric oxide and did not exhibit significant cytotoxic effects on macrophage cells.     

An efficient F-18 labeling method for PET study: Huisgen 1,3-dipolar cycloaddition of bioactive substances and F-18-labeled compounds

The Cu(I)-catalyzed, 1,3-dipolar cycloaddition reaction was applied successfully to the synthesis of small, F-18-labeled biomolecules, and an optimal condition was developed for one-pot, two-step reaction without any interim purifications. This technique was employed in various F-18-labeled, 1,2,3-triazole syntheses with high radiochemical yield.     

In Vitro Phytotherapeutic Properties of Aqueous Extracted Adenia viridiflora Craib. towards Civilization Diseases

Adenia viridiflora Craib. is an indigenous edible plant that became an endangered species due to limited consumption of the local population with unknown reproduction and growth conditions. The plant is used as a traditional herb; however, its health applications lack scientific-based evidence. A. viridiflora Craib. plant parts (old leaves and young shoots) from four areas as Kamphaeng Phet (KP), Muang Nakhon Ratchasima (MN), Pakchong Nakhon Ratchasima (PN), and Uthai Thani (UT) origins were investigated for phenolic compositions and in vitro health properties through the inhibition of key enzymes relevant to obesity (lipase), diabetes (α-glucosidase and dipeptidyl peptidase-IV), Alzheimer’s disease (cholinesterases and β-secretase), and hypertension (angiotensin-converting enzyme). Phenolics including p-coumaric acid, sinapic acid, naringenin, and apigenin were detected in old leaves and young shoots in all plant origins. Old leaves exhibited higher total phenolic contents (TPCs) and total flavonoid contents (TFCs), leading to higher enzyme inhibitory activities than young shoots. Besides, PN and MN with higher TPCs and TFCs tended to exhibit greater enzyme inhibitory activities than others. These results will be useful to promote this plant as a healthy food with valuable medicinal capacities to support its consumption and agricultural stimulation, leading to sustainable conservation of this endangered species.     

Metal-free selective synthesis of 2-substituted benzimidazoles catalyzed by Brönsted acidic ionic liquid: Convenient access to one-pot synthesis of N-alkylated 1,2-disubstituted benzimidazoles

A novel efficient method for the selective synthesis of 2-substituted benzimidazoles is described through condensation reaction of o-phenylenediamines with a wide rang of aliphatic, aromatic and heteroaromatic aldehyde substrates using Brönsted acidic ionic liquid as a reusable catalyst under metal-free conditions at ambient temperature. Notably, Dodecylimidazolium hydrogen sulfate ([DodecIm][HSO₄]) is the most efficient catalyst for good to excellent yields of the corresponding products (up to 98%). Subsequently, this protocol was successfully applied for the preparation of N-alkylated 1,2-disubstituted benzimidazoles in high to excellent yields via sequential one-pot reaction. In addition, catalysts are recycled at least four times without significant loss in activity.