(E)-4-[3'-(1-Adamantyl)-4'-hydroxyphenyl]-3-chlorocinnamic acid (3-Cl-AHPC) induces the cell cycle arrest and apoptosis of cancer cells. Because its pharmacologic properties-solubility, bioavailability, and toxicity-required improvement for translation, structural modifications were made by introducing nitrogen atoms into the cinnamyl ring and replacing its E-double bond with XCH(2) (X = O, N, and S) with the objective of enhancing these properties without impacting apoptosis-inducing activity. Analogues having nitrogen atoms in heterocyclic rings corresponding to the cinnamyl phenyl ring displayed equal or higher biological activities. The pyrimidine and pyridine analogues were more soluble in both phosphate-buffered saline and water. While the 2,5-disubstituted pyridine analogue was the most potent inducer of KG-1 acute myeloid leukemia cell apoptosis, on the basis of apoptotic activity in KG-1 cells and solubility, the 2,5-disubstituted pyrimidine proved to be the more promising candidate for treatment of acute myeloid leukemia.
Disinfection by-products (DBPs), formed from biofilm extracellular polymeric substances (EPS) and organic matter during regular disinfection practices in drinking water distribution systems, poses a potential threat to drinking water safety. However, the diverse DBP formations induced by the intertwined algal organic matter (AOM) and bacterial EPS remains elusive. In this study, we show substantial variations in EPS and DBP formation patterns driven by AOM biosorption with divalent ions (Ca and Mg).
Chitosan is a nontoxic biopolymer with many potential biomedical and material applications due to its biodegradability, biocompatibility, and antimicrobial properties. Here, fully atomistic molecular dynamics simulations and enhanced sampling methods have been used to study the adsorption mechanism of chitosan oligomers on a silica surface from an aqueous solution. The free energy of adsorption of chitosan on a silica surface was calculated to be 0.
The coordination number of metal single-atoms, being an important factor, should be precisely controlled as it affects both activity and specificity. Herein, the introduction of nitrogen into the para position of benzene in graphyne (2N-GY) is proposed as a carrier for anchoring metal single-atoms onto pyrazine nitrogen. These atoms are then coordinated to the center of the rhombic cavity, ensuring precisely controlled coordination numbers.
Electrochemical reduction of naturally abundant nitrogen (N) under ambient conditions is a promising method for ammonia (NH) synthesis, while the development of a highly active, stable and low-cost catalyst remains a challenge. Herein, the N reduction reaction of TM@g-BCN in electrochemical nitrogen reduction has been systematically investigated using density functional theory (DFT) calculations and compared with that of TM@g-CN. It was found that TM atoms are more stably anchored to g-BCN than to g-CN.
Inorganic Materials Research Laboratory, Department of Chemistry, Trent University, 1600 West Bank Dr., Peterborough, ON, Canada K9J 7B8. Electronic address:
2,4-dichlorophenoxy acetic acid (2,4-D) and 1,1-dimethyl-4,4-bipiridinium chloride (paraquat) are among the most widely used herbicides and are known to be toxic. Fabrication of green adsorbents which are capable of removing both herbicides remains a challenge. Here, we fabricate a novel adsorbent from tropical waste wood and use a facile, chitosan-mediated N-heteroatom functionalization technique to augment surface nitrogen and improve specific surface area.
