Synthesis, characterization, and antitumor activities of new palladium(II) complexes with 1-(alkyldithiocarbonyl)-imidazoles

<div><p>Pd(II) complexes with imidazole linked to dithiocarbamate derivatives were synthesized by reacting 1-(alkyldithiocarbonyl)-imidazoles with PdCl₂ in a 2 : 1 molar ratio. The complexes were characterized by elemental analyses, FT-IR, and ¹H NMR. The single crystal structure of <b>4</b> shows that the ligand is chelated by nitrogens in imidazole, instead of sulfur, to palladium. All synthesized compounds were tested for <i>in vitro</i> anticancer activities. Compound <b>5</b> had better activities in the HL-60 cell line and twofold better activities in the HeLa cell line than that of cisplatin.</p></div

Designing a Deep-Ultraviolet Nonlinear Optical Material with a Large Second Harmonic Generation Response

The generation of intense coherent deep-UV light from nonlinear optical materials is crucial to appli­ca­tions ranging from semiconductor photolithography and laser micromachining to photochemical synthesis. However, few materials with large second harmonic generation (SHG) and a short UV-cutoff edge are effective down to 200 nm. A notable exception is KBe₂BO₃F₂, which is obtained from a solid-state reaction of highly toxic beryllium oxide powders. We designed and synthesized a benign polar material, Ba₄B₁₁O₂₀F, that satisfies these requirements and exhibits the largest SHG response in known borates containing neither lone-pair-active anions nor second-order Jahn–Teller-active transition metals. We developed a microscopic model to explain the enhancement, which is unexpected on the basis of conventional anionic group theory arguments. Crystal engineering of atomic displacements along the polar axis, which are difficult to attribute to or identify within unique anionic moieties, and greater cation polarizabilities are critical to the design of next-generation SHG materials

Finding the Next Deep-Ultraviolet Nonlinear Optical Material: NH₄B₄O₆F

Nonlinear optical materials are essential for the development of solid-state lasers. KBe₂BO₃F₂ (KBBF) is a unique nonlinear optical material for generation of deep-ultraviolet coherent light; however, its industrial application is limited. Here, we report a new material NH₄B₄O₆F, which exhibits a wide deep-ultraviolet transparent range and suitable birefringence that enables frequency doubling below 200 nm. NH₄B₄O₆F possesses large nonlinear coefficients about 2.5 times that of KBBF. In addition, it is easy to grow bulk crystals and does not contain toxic elements

Pb₁₇O₈Cl₁₈: A Promising IR Nonlinear Optical Material with Large Laser Damage Threshold Synthesized in an Open System

Mid-IR nonlinear optical (NLO) materials are of great importance in modern laser frequency conversion technology and optical parametric oscillator processes. However, the commercially available IR NLO crystals (e.g., AgGaQ₂ (Q = S, Se) and ZnGeP₂) suffer from two obstacles, low laser damage thresholds (LDTs) and the difficulty of obtaining high-quality crystals, both of which seriously hinder their applications. The introduction of Cl, an element with a large electronegativity, and Pb, a relatively heavy element to promote the optical properties, affords an oxide-based IR NLO material, Pb₁₇O₈Cl₁₈ (POC). High-quality POC single crystals with sizes of up to 7 mm × 2 mm × 2 mm have been grown in an open system. Additionally, POC exhibits a large LDT of 408 MW/cm², 12.8 times that of AgGaS₂. POC also exhibits an excellent second harmonic generation response: 2 times that of AgGaS₂, the benchmark IR NLO crystal at 2090 nm, and 4 times that of KDP, the standard UV NLO crystal at 1064 nm. Thus, we believe that POC is a promising IR NLO material

CHA structure and its effect on RD cell viability.

<p>(A) The structure of CHA. (B) Control: control ; DMSO: 0.1% DMSO was added in RD cells. CHA was serially diluted as different concentrations (160,80,40,20,10,5 and 2.5 µg/mL) in triplicate. After 2 days of incubation, the cytotoxicity of CHA was determined by MTT assay. Data were presented as mean ± S.D. of three independent experiments.</p

CHA inhibits EV71 replication in RD cells.

<p>RD cells (5×10⁶) were infected with EV71 at a MOI of 5 in the presence or absence of CHA (20 µg/ml) and ribavirin (40 µg/ml). CHA and ribavirin were added with EV71 at the same time or absorbation for 1 h. Then cell supernatants were collected at 0, 4, 8,12, 16, 20, 24,28, 32 and 36 h p.i. and the viral titers were determined by a plaque forming assay. Each point represents the mean ± S.D. of three independent experiments (*** <i>p</i> < 0.001).</p

Effects of CHA on EV71 replication.

<p>Ribavirin was used as positive control and 0.1% DMSO as negative control. Inhibitory effects of ribavirin and indicated concentration of CHA on EV71 replication were determined by a plaque reduction assay. Data were represented as mean ± S.D. of three independent experiments.</p

Effects of CHA on EV71 replication before or after viral infection.

<p>DMSO: EV71 infection with DMSO. CHA: EV71 infection with DMSO and CHA RD cells (5 × 10⁶) were infected with EV71 (5 MOI) and CHA (20 µg/ml) was added at the indicated time. Cell supernatants were collected at 25 h p.i. and EV71 titers were determined by a plaque forming assay. Each bar represents the mean ± S.D. of three independent experiments（** <i>p</i> < 0.01, *** <i>p</i> < 0.001).</p

EV71 infection stimulates cytokine secretion.

<p>Control: Uninfected RD cells; EV71: RD cell-infected with EV71 (MOI = 5); CHA: EV71 infection in the presence of CHA (20 µg/ml). RD cells were absorbed with EV71 for 1h, and then treated with or without CHA(20 µg/ml). Culture supernatants were collected at 8h, 12h, and 20h. The concentrations of IL-2, IL-6, IL-10, TNF-α, IFN-γ and MCP-1 were detected by luminex fluorescent technique. The data were expressed as mean ± SE from 3 independent experiments. ** <i>P</i> < 0.01 and ***<i>P</i> < 0.001 by two-way ANOVA.</p

Cs₃Zn₆B₉O₂₁: A Chemically Benign Member of the KBBF Family Exhibiting the Largest Second Harmonic Generation Response

Nonlinear optical (NLO) crystals are essential materials for generation of coherent UV light in solid state lasers. KBBF is the only material that can achieve coherent light below 200 nm by direct second harmonic generation (SHG). However, its strong layer habits and the high toxicity of the beryllium oxide powders required for synthesis limit its application. By substituting Be with Zn and connecting adjacent [Zn₂BO₃O₂]_∞ layers by B₃O₆ groups, a new UV nonlinear optical material, Cs₃Zn₆B₉O₂₁, was synthesized. It overcomes the processing limitations of KBBF and exhibits the largest SHG response in the KBBF family