Solvothermal Synthesis,Crystal Structure and Luminescent Property of a Two-dimensional Lead(Ⅱ) Compound：[Pb(bmzbc)2]n

A two-dimensional coordination polymer, [Pb（bmzbc）2]n（1）（Hbmzbc =4-benzimidazole-1-yl-benzoic acid）, has been synthesized by the solvothermal reaction of Pb（NO3）2 with Hbmzbc at 120 ℃ in ethanol solvent. Compound 1 has been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetry analysis, and IR spectrum. Compound 1 crystallizes in the orthorhombic system, space group Pccn, with a = 12.5801（7）, b = 20.0795（11）, c = 9.1830（6） ？, V = 2319.6（2） A^3, Z = 4, C（28）H（18）N4O4Pb, Mr = 681.65, Dc = 1.952 g/cm^3, μ = 7.319 mm^-1, F（000） = 1312, the final R = 0.0336 and wR = 0.0965 for 1699 observed reflection with I 〉 2σ（I）. In 1, the bmzbc^– ligands bridge the Pb（Ⅱ） ions to generate a 2-D sheet with（4, 4） topology. The complex exhibits turquoise photoluminescent emission with a maximum at 480 nm upon excitation at 300 nm.

Growth and Application of Chalcogenides of Lead and Related Compounds

Large grain, low-dislocation, high-quality single crystals of various Pb-salt compounds have been grown reproducibly by the Horizontal Unseeded Vapor Growth (HUVG) technique. The Tunable Diode Lasers with better performance have been made with such crystals. The annealing feature, dislocations and diffusion in the crystals have also been investigated.

Natural Products as Potential Lead Compounds for Drug Discovery Against SARS-CoV-2

For the past 2 years,the coronavirus responsible for the COVID-19 infection has become a world pandemic,ruining the lives and economies of several nations in the world.This has scaled up research on the virus and the resulting infection with the goal of developing new vaccines and therapies.Natural products are known to be a rich source of lead compounds for drug discovery,including against infectious diseases caused by microbes(viruses,bacteria and fungi).In this review article,we conducted a literature survey aimed at identifying natural products with inhibitory concentrations against the coronaviruses or their target proteins,which lie below 10μM.This led to the identification of 42 compounds belonging to the alkaloid,flavonoid,terpenoid,phenolic,xanthone and saponin classes.The cut off concentration of 10μM was to limit the study to the most potent chemical entities,which could be developed into therapies against the viral infection to make a contribution towards limiting the spread of the disease.

<i>In-Silico</i>Identification of Anticancer Compounds;Ligand-Based Pharmacophore Approach against EGFR Involved in Breast Cancer

Objective: Breast cancer is a public health challenge on a global scale that is caused by environmental or genetic factors. Breast cancer is affecting both males and females, but there is still a lack of effective drugs with improved potency and admissibility against breast cancer as many of the breast cancer drugs have severe side effects. Methods: The docking approach has been used to find a new compound for breast cancer with more efficacy and tolerance and with lesser side effects. A ligand-based pharmacophore approach has been generated for 39 anticancer compounds with significance for the development of new drugs. Result: Through docking, the approach found new lead compounds for breast cancer. The proposed pharmacophore model in this study contains two HBAs and one HYD, one hydrophobic domain and two Aromatic rings and the estimated distance range is minimum to maximum of derived pharmacophore features. Conclusion: Based on this research, it is proposed that these two lead compounds may be able to be used against EGFR in breast cancer. New compounds can be identified based on common features in the Pharmacophore model. 3D pharmacophore triangle could be used for further studies because this pharmacophore has better merging and in the future for more studies can suggest the same distance range of pharmacophore features as this pharmacophore.

Effect of Pb Content on Phase Composition and Property of Bi-Pb-Sr-Ca-Cu-O System Superconductors

The addition of Pb in the superconductors of BiSrCaCuO system is very helpful for growth of the high-Tc phase (Tc 110K). We prepared a series of samples with nominal composition of Bi2-xPbxSr2Ca2Cu3Oy (0.1&lex&le2). The zero resistance transition temperature Tc of 106K and the critical transport current density Jc of 1 × 103A/cm2 at 77K have been obtained for the samples of Bi2-xPbxSr2Ca2Cu3Oy (x=0.2 and 0.3). The X-ray diffraction analysis and measurement of AC magnetic susceptibility confirmed that the material is comprised of single high-Tc phase. We also report the magnetic properties of this material as well as the results of TEM observation.

Marine soft corals as source of lead compounds for anti-inflammatories

Marine soft corals are known to produce a wide array of secondary metabolites,particularly diterpenoids and steroids,and often characterized by uncommon structural features and potent bioactivities.The remarkable abundance and diversity of bioactive small molecule which have been isolated from soft corals have made these organisms an important source of new drug candidates for human diseases,particularly for their anti-inflammatory activity.In this paper,the authors reported anti-inflammatory marine natural products isolated from diverse species of soft corals determined in vitro by their inhibition of lipopolysaccharide-induced expression of inducible NO synthase and cyclooxygenase-2 in murine macrophage cells(RAW 264.7).

Current natural products with antihypertensive activity

Natural products have been an important source of new drugs, which also played a dominant role in the discovery and research of new drugs for the treatment of hypertension. This review article reviews the recent progress in the research and development of natural lead compounds with antihypertensive activity, including alkaloids, diterpenes, coumarins, flavonoids, and peptides. We summarized their structures, sources, as well as the antihypertensive mechanisms. These information provides instructive reference for the following structural modifications and optimization.

Characteristics of a PLZT electro-optical deflector

A beam deflector was designed and fabricated by using a lead lanthanum zirconate titanate （PLZT） ceramic with high quadratic electro-optic （EO） effect, based on refraction at an interface between areas with and without applied voltage. Its EO coefficients of R33 = 2.1×10^-16 V^2/m^2 and R13 = -0.37×10^-16 V^2/m^2 were obtained. Moreover, the hysteresis characteristics of the EO deflection were observed, and the effects of temperature on the characteristics of beam deflector were also investigated in detail.

Portable infrared spectral radiance measurement apparatus based on PbSe detectors

A portable infrared spectral radiance measurement apparatus without the cooling based on PbSe detectors is designed to measure the spectral radiance of the object in the wavelength range from 2.1 to 4.1μm. Cores Luxell 256 module is applied which integrates 256 pixel line array PbSe detectors, amplifiers, analog-to-digital convertors, and Universal Serial Bus output interface. Electric aperture is applied to eliminate the effect of temperature drift. Wavelength and response function of the apparatus is calibrated with the blackbody. Results show that the wavelength resolution is 10 nm. The relative error of measured spectral radiance is below 2.3%.

Synthesis and evaluation of peptide-fentanyl analogue conjugates as dualμ/δ-opioid receptor agonists for the treatment of pain

Novel peptide-fentanyl analogue conjugates were synthesized by the covalent coupling of carfentanyl derivatives to the C-terminus or N-terminus of the conformationally constrained dermorphin tetrapeptide BVD03 via a chemical linker.The carfentanyl-related analogues displayed distinct binding and functional activities atμ/δopioid receptors(MOR/DOR)and antinociceptive effects when conjugated to the peptide.The most potent compound,SW-LJ-11,displayed mixed MOR/DOR agonist properties in the low nanomolar range and significant analgesic efficacy in vivo in four classic mouse models of pain.Interestingly,SW-LJ-11 did not exhibit any physical dependence or respiratory depression,in contrast to an equipotent analgesic dose of morphine or BVD03,indicating that the use of opioid peptide-fentanyl analogue conjugates as dual MOR/DOR agonists may be a promising strategy for obtaining safer opioids.

Synthesis and Structural Characterization of Two Lead（Ⅱ） Complexes of Bis（3,5-dimethylpyrazolyl）methane

Reactions of lead（Ⅱ） nitrate or perchlorate with bis（3,5-dimethylpyrazolyl）methane （dmpzm）, produced two new Pb（Ⅱ） chelated complexes [Pb（dmpzm）2X2] （X=NO3^- 1, ClO4^- 2）. Both compounds were structurally characterized by elemental analysis, IR spectroscopy, thermal analysis, and single crystal X-ray diffraction. Both compounds are mononuclear with a distorted square antiprismatic PbN4O4 coordination geometry incorporating a pair of O,O＇-bidentate anions and N,N＇-bidentate dmpzm ligands. In the crystals of 1 or 2, the methyl or methylene groups of dmpzm ligand interact with the oxygen atoms of nitrates or perchlorates to afford intra- and intermolecular hydrogen bonding, thereby forming a two-dimensional network 1 or a three-dimensional structure 2.