A convenient synthesis of a selective gelatinase inhibitor as an antimetastatic agent

Compound 1, 2-(4-phenoxyphenylsulfonylmethyl)thiirane, is a potent and selective inhibitor for human gelatinases (J. Am. Chem. Soc. 2000, 122, 6799-6800), enzymes implicated in a number of diseases, including cancer. This compound is showing excellent promise in animal trials in a number of disease models. Large quantities of this compound were necessary for these studies. A convenient four-step synthetic route for compound 1 is described herein. The synthesis is amenable to scale-up to tens of grams and gives an overall yield of 57% for this important compound.     

On the mechanism of growth of cells (Bacillus amyloliquefaciens) in the mixed aqueous two-phase system

The growth ofBacillus amyloliquefaciens in the aqueous two-phase system, made up of polyethylene glycol, dextran, and water, was investigated. Generally,Bacillus partitions in the dextran phase, but the magnitude of the separation depends largely on the overall composition of polymers in the phase system. The kinetics of growth ofBacillus amyloliquefaciens was studied in the polyethylene glycol-rich continuous phase, dextran-rich dispersed phase, and in the mixed phase. From the kinetic data it appears that increasing the overall polymer composition causes the cells to adsorp at the interface. On the other hand, partition measurements indicate that increasing polymer concentrations make the cell partitioning more one-sided. This anomaly is explained by studying the interfacial adsorption of cells via dynamic surface tension measurements.     

Design, synthesis, and evaluation of a mechanism-based inhibitor for gelatinase A

[structure: see text] Matrix metalloproteinases (MMPs), of which 26 are known, have been implicated in a number of pathological conditions, including tumor metastasis. We have previously described the first mechanism-based inhibitor for MMPs (J. Am. Chem. Soc. 2000, 122, 6799-6800), which in chemistry mediated by the active site zinc ion selectively and covalently inhibits MMP-2, -3, and -9. Computational analyses indicated that this selectivity in inhibition of MMPs could be improved by design of new variants of the inhibitor class. We report herein the syntheses of methyl 2-(4-{4-[(2-thiiranylpropyl)sulfonyl]phenoxy}phenyl)acetate (3) and 2-(4-{4-[(2-thiiranylpropyl)sulfonyl]phenoxy}phenyl)acetic acid (4), and show that compound 3 serves as a mechanism-based inhibitor exclusively for MMP-2. This molecule should prove useful in delineating the functions of MMP-2 in biological systems.     

Structural Basis for Carbapenemase Activity of the OXA-23 β-Lactamase from Acinetobacter baumannii

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Synthesis, Characterization, Spectroscopy and Study of Antimicrobial Properties of Two New Substituted Trichloroaluminate（Ⅲ） Complexes [AlCl3X]- （X = SCN-, CN-）

The synthesis and characterization of two new aluminate(Ⅲ) complexes with general formula K[AlCl3X] are reported. These compounds derived from aluminate trichloride and related salts. Potassium trichlorothiocyanoaluminate, PCTA, and potassium trichlorocyanatoalu-minate, PCCA, are two new ionic aluminate complexes. They can be easily synthesized in a nearly quantitative yield by using the direct reaction of AlCl3 and KX. The complexes were characterized by physico-chemical and spectroscopic methods. Theoretical calculations have been used for the extraction of structural and spectroscopic data of these new synthesized complexes. The antibacterial activities of such compounds were studied against the Staphylococcus aureus, Escherichia coli, Staphylococcus Epidermidis, Estreptococo B and Shigella.     

Convergence of zeta functions of graphs

The -zeta function of an infinite graph (defined previously in a ball around zero) has an analytic extension. For a tower of finite graphs covered by , the normalized zeta functions of the finite graphs converge to the -zeta function of .

     

Demonstration of a simple technique for determining the M/# of a holographic substrate by use of a single exposure

We propose and demonstrate a simple technique for determining the M/# parameter of a holographic recording material. In this method, divergent object and reference beams are used to produce a spatially varying index modulation. One can analyze the resultant diffraction pattern to find M/# by using only a single grating; existing techniques require many gratings.