Molecular structure of 2-methoxy-4-pyrrolidinyl-6-trinitromethyl-1,3,5-triazine

An X-ray diffraction study of 2-methoxy-4-pyrrolidinyl-6-trinitromethyl-1,3,5-triazine was carried out. The crystals are triclinic; C₉H₁₁N₇O₇; M = 329.25; a = 8.536(1) Å, b = 9.378(2) Å, c = 9.7401(8) Å; α = 79.13(1)°, β = 73.974(8)°; γ = 72.76(1)°; V = 710.8(2) ų, d _c = 1.54 g/cm³, Z = 2, space group P1ˉ. The molecule on the whole is planar, except the pyrrolidine ring, which has a twist conformation. No significant π-π interactions and hydrogen bonds of C-H⋯N or C-H⋯O type were found in the crystal, and the molecule packing is stabilized only due to van der Waals interactions. Original Russian Text Copyright ? 2008 by V. V. Bakharev, A. A. Gidaspov, I. A. Litvinov, and E. V. Mironova __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 1, pp. 187–189, January–February, 2008.     

Pure Organic Phase Phenol Biosensor Based on Tyrosinase Entrapped in a Vapor Deposited Titania Sol‐Gel Membrane

A novel amperometric biosensor was constructed for the determination of phenols in pure organic phase. This biosensor was fabricated by immobilizing tyrosinase in a titania sol‐gel membrane which was obtained with a vapor deposition method. This method was facile and avoided the calcination step needed in conventional titania sol‐gel process. The titania sol‐gel membrane could effectively retain the essential water layer around the enzyme molecule needed for maintaining its activity in organic phase. The experimental parameters such as solvent and operating potential were optimized. At ?100 mV this biosensor showed a good amperometric response to phenols in pure chloroform without any mediator and rehydration of the enzyme. For catechol determination the sensor exhibited a fast response of less than 5 seconds. The sensitivity of different phenols was as follows: catechol > phenol > p‐cresol. Additionally, the apparent Michaelis‐Menten constants of the encapsulated tyrosinase to catechol, phenol and p‐cresol were found to be 0.15±0.003, 0.17±0.008 and 0.21±0.004 mM, respectively. The biosensor had also good reproducibility and stability. This work provided a promising platform for the construction of pure organic phase biosensors and the determination of substrates with poor water solubility.     

Metal–Organic Spheres as Functional Systems for Guest Encapsulation

Music of the spheres : Infinite coordination polymerization of Zn²⁺ ions and a multitopic ligand produces metal–organic micro‐ and nanospheres that can be used as functional matrices. The spheres can encapsulate combinations of active substances, such as organic dyes, magnetic nanoparticles, or luminescent quantum dots (see image), which results in spheres that are luminescent in the blue, green, and red regions of the spectrum.

     

煤中有机硫形态结构和热解过程硫变迁特性的研究

利用热解 质谱并结合固定床热解反应装置，对煤中有机硫的形态主其对加氢热解过程 变迁特性的影响，进行了较系统的研究。结果表明，煤中有机硫的形态结构在褐煤中主要以脂肪族、芳香族硫化物为主，而在 煤中则主要以各种不同芳构化程度的噻吩结构为主，初步表明煤中有机硫形态结构随煤变质程度的变迁呈较强的连续递变性。煤热解过程中硫在呼产物中的变迁和分布与煤中有机硫的形态结构特点密切相关。较高芳构化噻吩结构不完全的氧     

Functional mixed metal-organic frameworks with metalloligands

Immobilization of functional sites within metal-organic frameworks (MOFs) is very important for their ability to recognize small molecules and thus for their functional properties. The metalloligand approach has enabled us to rationally immobilize a variety of different functional sites such as open metal sites, catalytic active metal sites, photoactive metal sites, chiral pore environments, and pores of tunable sizes and curvatures into mixed metal-organic frameworks (M'MOFs). In this Minireview, we highlight some important functional M'MOFs with metalloligands for gas storage and separation, enantioselective separation, heterogeneous asymmetric catalysis, sensing, and as photoactive and nanoscale drug delivery and biomedical imaging materials.     

Growth Mechanism of Metal–Organic Frameworks: Insights into the Nucleation by Employing a Step‐by‐Step Route

One step at a time : The in situ monitoring of the step‐by‐step formation of metal–organic frameworks (MOFs) by using surface plasmon resonance (SPR), allows the nucleation process and the formation of the secondary building units to be investigated. Growth rates on functionalized organic surfaces with different crystallographic orientations can also be studied.

     

Synthesis of unsymmetrically substituted pyrene derivatives through (6-bromo-3,8-dibutylpyren-1-yl)trimethylsilane

A straightforward route to unsymmetrically functionalized pyrene derivatives is described involving the synthesis of key precursor (6-bromo-3,8-dibutylpyren-1-yl)trimethylsilane 1. In a first step bromide 1 was successful in Suzuki-Miyaura, Sonogashira, and Buchwald-Hartwig cross-coupling reactions. Subsequent transformation of the trimethylsilyl group to bromide enabled the introduction of a second variable functional group onto the pyrene skeleton.     

APPLICATION OF MSW-X_α METHOD WITH OVERLAPPING ATOMIC-SPHERE TO IONIZATION POTENTIALS FOR SOME PLANAR ORGANIC MOLECULES

Application of multiple scattered-wave X_α method with overlapping atomic-sphere to ionization potentials is reported for benzene, pyridine, pyrazine, pyrrole and imidazole. The calculated results show that the orbital charges in the intersphere region are non-negative and the energy levels get improvements in orderings.     

Establishment of A431 cell membrane chromatography-RPLC method for screening target components from Radix Caulophylli

We describe here an analytical method of A431 cell membrane chromatography (A431/CMC) (CMC, cell membrane chromatography) combined with RPLC for recognition, separation, and identification of target components from traditional Chinese medicines (TCMs) Radix Caulophylli. The A431 cells with high expressed epidermal growth factor receptor (EGFR) were used to prepare the stationary phase in the CMC model. Retention fractions on the A431-CMC model were collected using an automated fraction collection and injection module (FC/I). Each fraction was analyzed by RPLC under the optimized conditions. Gefitinib and erlotinib were used as standard compounds to investigate the suitability and reliability of the A431 cell membrane chromatography-RPLC method prior to screening target component from Radix Caulophylli total alkaloids. The results indicated that caulophine and taspine were the target component acting on the epidermal growth factor receptor. This method could be an efficient way in drug discovery using natural medicinal herbs as a source of novel compounds.