Sintokamides A to E, chlorinated peptides from the sponge Dysidea sp. that inhibit transactivation of the N-terminus of the androgen receptor in prostate cancer cells

The new chlorinated peptides sintokamides A to E (1-5) have been isolated from specimens of the marine sponge Dysidea sp. collected in Indonesia. Their structures were elucidated by a combination of spectroscopic and single-crystal X-ray diffraction analyses. Sintokamide A (1) is an inhibitor of N-terminus transactivation of the androgen receptor in prostate cancer cells.     

Immobilized copper(II) on nitrogen‐rich polymer‐entrapped Fe3O4 nanoparticles: a highly loaded and magnetically recoverable catalyst for aqueous click chemistry

A heterogeneous magnetic copper catalyst was prepared via anchoring of copper sulfate onto multi‐layered poly(2‐dimethylaminoethyl acrylamide)‐coated magnetic nanoparticles and was characterized using various techniques. The catalyst was found to be active, effective and selective for one‐pot three‐component reaction of alkyl halide, sodium azide and alkyne, known as copper‐catalyzed click synthesis of 1,2,3‐triazoles. As little as 0.3 mol% of catalyst was found to be effective under the optimum conditions. The catalyst could also be recycled and reused up to seven times without significant loss of activity. Thermal stability, high loading level of copper on catalyst, broad diversity of alkyl/benzyl/allyl bromide/chloride and alkyl/aryl terminal alkynes without isolation of azide intermediate, and good to excellent yields of products make this procedure highly economical. Copyright © 2015 John Wiley & Sons, Ltd.     

Kinetic Study of the Electro‐Catalytic Oxidation of Acetaldehyde on Copper Electrode

Electrocatalytic oxidation of acetaldehyde was investigated on a copper electrode in alkaline solution. The process of oxidation involved and its kinetics were established by using cyclic voltammetry and chronoamperometry techniques as well as steady state polarization measurements. It has been found that in the course of an anodic potential sweep the electro‐oxidation of acetaldehyde follows the formation of Cu(III) and is catalysed by this species through a mediated electron transfer mechanism. A mechanism based on the electrochemical generation of Cu(III) active sites and their subsequent consumption by the acetaldehyde in question was also investigated.     

Single facility location and relocation problem with time dependent weights and discrete planning horizon

In this paper a single facility location problem with multiple relocation opportunities is investigated. The weight associated with each demand point is a known function of time. We consider either rectilinear, or squared Euclidean, or Euclidean distances. Relocations can take place at pre-determined times. The objective function is to minimize the total location and relocation costs. An algorithm which finds the optimal locations, relocation times and the total cost, for all three types of distance measurements and various weight functions, is developed. Locations are found using constant weights, and relocations times are the solution to a Dynamic Programming or Binary Integer Programming (BIP) model. The time horizon can be finite or infinite.     

New 7-piperazinylquinolones containing (benzo[<Emphasis Type="BoldItalic">d</Emphasis>]imidazol-2-yl)methyl moiety as potent antibacterial agents

A series of 7-piperazinylquinolones containing a (benzo[d]imidazol-2-yl)methyl moiety were designed and synthesized as new antibacterial agents. The antibacterial activity of title compounds was evaluated against Gram-positive (Staphylococcus aureus, Staphylococcus epidermidis and Bacillus subtilis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia) microorganisms. Among the tested compounds, the N1-cyclopropyl derivative 4a showed the highest activity against S. aureus, S. epidermidis, B. subtilis and E. coli (\(\text {MIC} = 0.097\) \(\upmu \)g/mL), being 2–4 times more potent than reference drug norfloxacin. A structure-activity relationship study demonstrated that the effect of the nitro group on the benzimidazole ring depends on the pattern of substitutions on the piperazinylquinolone.     

New N-nicotinyl and N-isonicotinyl, N′,N″-diaryl phosphorictriamides with new Er(III) complex: synthesis, spectroscopic study and crystal structures

Ten new N-nicotinyl and N-isonicotinyl phosphoramidates with formula XP(O)R₂, X?=?Nicotinamide(nia), R?=?NHCH₂Ph (1), N(CH₃)CH₂Ph (2), NHCH(CH₃)Ph (3), NH-CH₂C₄H₃O (4), NHCH₂(C₅H₄N) (5), 3-NH-C₅H₄N (6), and YP(O)R₂, Y?=?isonicotinamide(iso), R?=?NHCH₂Ph (7), N(CH₃)CH₂Ph (8), NHCH(CH₃)Ph (9), NH-CH₂C₄H₃O (10) plus one new Er(III) complex with formula Er(L)₂(NO₃)₃ (11), L?=?(iso)PO(NHCH₂C₄H₃O)₂ (10), were synthesized and characterized by elemental analysis and ¹H, ¹³C, ³¹P NMR, IR, UV?Cvis spectroscopy. Crystal structures of compounds 10 and 11 were also determined by X-ray crystallography. Interestingly, the ¹H NMR spectra of compounds 1, 2, 6, 7, 9 indicated long-range ⁿ J _P,H (n?=?5,6,7) coupling constants, in the range of 1.4?C1.9?Hz, for the splitting of pyridine ring protons with phosphorus atom. IR results showed that the ??(C=O) values of compounds 7?C10 are greater than those of compounds 1?C5 which means that isonicotinyl moiety is more electron withdrawing than nicotinyl group. X-ray outcomes revealed that in complex 11 three phosphoric triamide ligands have been connected to each Er(III); one from N_pyridine and two from P=O donor sites. One of the P=O donor ligands is mono dentate while the other one acts as a bidentate ligand and coordinates to another Er atom via its N_pyridine site. By forming complex 11 the P=O and C?CN_amide bond lengths of ligand is increased in both, mono and bi dentate, ligands while the C=O bond length is decreased to lower values. These variations are in good agreement with IR results. All H-bonds and electrostatic interactions lead to form a three-dimensional polymeric cluster in the crystal lattice of 10 and 11.     

Chromium Trioxide Supported onto Wet Silica Gel: Rapid Oxidation of Alcohols to Carbonyl Compounds Under Microwave Irradiation in Solventless System

In an environmentally benign system, alcohols are rapidly oxidized to carbonyl compounds using CrO 3 supported onto wet silica gel as an oxidant under microwave irradiation.