"Uncorking" of liposomes by matrix metalloproteinase-9

A triggered release methodology of liposomal contents via the enzyme MMP-9 is described.     

Spiropyrans and spirooxazines. 1. Synthesis and photochromic properties of 9"-hydroxy- and 9"-alkoxy-substituted spironaphthooxazines

A procedure was developed for phase-transfer catalyzed alkylation of 5-hydroxyindolenine and 9"-hydroxy-substituted spiro[indoline-2,3"-naphtho[2,1-b]oxazines] by alkyl halides. New 9"-hydroxy- and 9"-alkoxy-substituted spironaphthooxazines, spirooxazinyloxyacetic acids, and their esters containing substituents with different length of the carbon chain in the indoline moiety were synthesized. The influence of the substituents on the spectroscopic properties of the starting and colored forms and the kinetic characteristics of photochromic transformations of 9"-substituted spironaphthooxazines in solutions and polymeric films was investigated. The bipolar merocyanine forms of spirooxazines were found to produce H-aggregates.     

稀土元素对Y-9裂化催化剂的改进

提高催化裂化催化剂再生时焦炭燃烧程度是一个很有经济效益的问题。目前国内外多半在催化剂中添加铂等贵金属来提高焦炭的燃烧速率。木文以异丙苯为对象用稀土对"Y-9"裂化催化剂进行改进,得到了明显的效果。     

Inhibition of matrix metalloproteinase-9 by "multi-prong" surface binding groups

A novel strategy of blocking the active site accessibility of MMP-9 by "multi-prong" surface binding groups is described.     

N-aryl-9-amino-substituted acridizinium derivatives as fluorescent "light-up" probes for DNA and protein detection

[reaction: see text] N-Arylamino-substituted acridizinium (benzo[b]quinolizinium) derivatives are almost nonfluorescent in water or organic solvents; however, upon addition of calf thymus DNA or bovine serum albumin the fluorescence intensity increases by a factor of 10 to 50. Thus, these dyes exhibit ideal properties to be used as DNA- and protein-sensitive "light-up probes".     

"Water-stable boron-iodinated dicarbollide dianions [7,8-nido-C2H2B9I9]2- and [7,8-nido-C2H2B9I8H]2-"

The reaction of 3,4,5,7,8,9,10,11,12-I(9)-1,2-closo-C(2)B(10)H(3) with KOH/EtOH gave a mixture of the boron periodinated [1,2,3,4,5,6,9,10,11-I(9)-7,8-nido-C(2)B(9)H(2)](2-) and the highly iodinated on boron [1,2,4,5,6,9,10,11-I(8)-7,8-nido-C(2)B(9)H(3)](2-) in approximately 50% each. Moreover, 3,4,5,6,7,8,9,10,11,12-I(10)-1,2-closo-C(2)B(10)H(2) was reacted with KOH/EtOH to purely produce [1,2,3,4,5,6,9,10,11-I(9)-7,8-nido-C(2)B(9)H(2)](2-). It is the first dinegative dicarbollide stable in water or protic solvent reported in literature.     

Ge9=Ge9=Ge9=Ge9]8-: a linear tetramer of nine-atom germanium clusters,a nanorod

A tetramer of nine-atom deltahedral germanium clusters and charge 8-, [Ge9=Ge9=Ge9=Ge9]8- , has been characterized as a (Rb-18C6)(+) salt (18C6 = 18-crown-6 polyether). The clusters are connected by pairs of parallel bonds, and the electrons are delocalized over the whole anion. The size of the tetramer is of nanorod dimensions, ca. 2 nm.     

"Decoking" of a "coked" zeolite catalyst in a glow discharge

'Decoking' of a 'coked' zeolite catalyst in a glow discharge in oxygen is investigated. The 'decoking' process involves reactions of atomic oxygen (O atoms) with 'coke' and yields gases such as CO, CO₂ as well as other gaseous products that could be easily pumped out.Three different modes of discharge were investigated including a static mode, a flowing-gas mode, and a periodic-purge mode where the oxygen and other gaseous products of the discharge were replaced by fresh O₂ gas after short but regular intervals of time. In some cases, additional heating was also used to provide base temperatures of the order of 100 °C to facilitate penetration of oxygen atoms into the inner layers and cages of the zeolite catalyst.This paper presents some results of spectroscopic analytical techniques used to monitor the atomization of oxygen, oxidation of 'coke', and to confirm the process of 'decoking'. More specifically, radiation emission on the 3 s ⁵S– 3p ⁵P transitions of O around 777.2–777.5 nm were selected for monitoring the atomization of O₂. On the other hand, X-ray photo-electron spectroscopy (XPS) was used to determine the amount of residual carbon and extent of 'decoking'. Furthermore, evolution of CO and CO₂ gases as a function of time was systematically monitored in real time. For CO, the 451.1 nm band head belonging to the B¹ - A¹ bands of the Angstrom system of the CO spectrum was used, while for CO₂, the band head at 353.4 nm belonging to the CO₂⁺ spectrum was used. The rates of evolution of CO and CO₂ were related to the rate of 'decoking' of the catalyst. It is noted that in the periodic-purge mode, about 63% of the total yield of CO from a given sample of the catalyst appears in the first 3-min exposure to discharge whereas it takes up to 15 min to remove nearly 94% of the removable carbon under our experimental conditions.     

Synthesis of 9-alkylidene-9H-fluorenes by a novel palladium-catalyzed rearrangement

In the presence of a palladium catalyst and NaOAc, aryl iodides react with 1-aryl-1-alkynes to afford 9-alkylidene-9H-fluorenes in good yields. This process appears to involve (1) oxidative addition of the aryl iodide to Pd(0), (2) alkyne insertion, (3) rearrangement of the resulting vinylic palladium intermediate to an arylpalladium species, and (4) aryl-aryl coupling with simultaneous regeneration of the Pd(0) catalyst.     

Two nickel(II) complexes exhibiting "fused" 9-MC-3 and 12-MC-4 metallacrowns

Transition Metal Chemistry - The reactions of (E)-quinoline-2-carbaldehyde oxime (Hqcah) with Ni(ClO4)2·6H2O and NH4SCN and with Ni(CF3SO3)2 and NaN3 led to two solitary metallacrowns (MCs)...     

Colorimetric response to anions by a "robust" copper(II) complex of a [9]aneN3 pendant arm derivative: CN- and I- selective sensing

The 1 : 1 complex [Cu(L)](BF(4))(2)·MeCN (1) of the tetradentate ligand 1-(2-quinolinylmethyl)-1,4,7-triazacyclononane (L) selectively changes its colour in the presence of CN(-) in H(2)O and MeCN (without undergoing decomplexation from the macrocyclic ligand). The same complex in MeCN assumes different colours in the presence of CN(-) or I(-).     

Synthesis and characterization of 9-(cycloheptatrienylidene)fluorene derivatives: acid-triggered "switch on"of fluorophores

A series of 9-(cycloheptatrienylidene)fluorene derivatives were synthesized in good yields through the Suzuki or Sonogashira cross-coupling reactions. Fluorescence "off-on" behaviors of these compounds were investigated on the basis of variable acid concentrations. These compounds were shown to be acid-sensing fluorophores with utility as indicators in acidic environments.     

9-H-9-Borafluorene dimethyl sulfide adduct: a product of a unique ring-contraction reaction and a useful hydroboration reagent

The dimethyl sulfide adduct 2(DMS) is a crystalline storage form of the unstable hydroboration reagent 9-H-9-borafluorene (2); 2(DMS) is available by the addition of DMS to either in situ generated [2](2) or 1,2-(2,2'-biphenylylene)diborane(6) (7).