Polymeric enzyme mimics: catalytic activity of ribose-containing polymers for a phosphate substrate

The polymers containing ribose rings: poly(5'-acrylamido-5'-deoxy-1',2'-O-isopropylidene-alpha-D-ribose) (11), poly(5'-acrylamido-5'-deoxy-alpha-D-ribose) (12) and poly(5'-acrylamido-5'-deoxy-1'-O-methyl-D-ribose) (13) were prepared as enzyme mimics. Polymers 12 and 13 with free vic-cis-diol groups catalyzed the hydrolysis of phosphodiester (ethyl p-nitrophenyl phosphate and N-methylpyridinium 4-tert-butylcatechol cyclic phosphate) and phosphomonoester substrates with a rate acceleration of 10 approximately equal to 10(3) compared with the uncatalyzed reaction. They also catalyzed the reverse reactions, i.e., the esterification of phosphomonoester to phosphodiester and the phosphorylation of alcohols with phosphate ions. The catalytic activity was attributable to the vic-cis-diols of riboses on polymer chains, which formed hydrogen bonds with two phosphoryl oxygen atoms of phosphates so as to activate the phosphorus atoms to be attacked by nucleophiles. The catalytic activity was negligible for polymer 11 where vic-cis-diol groups were blocked with isopropylidene groups. The catalytic activity was attributable to the vic-cis-diols of riboses on polymer chains, which formed hydrogen bonds with two phosphoryl oxygen atoms of phosphates so as to activate the phosphorus atoms to be attacked by nucleophiles.     

Highly enantioselective iridium-catalyzed hydrogenation of heteroaromatic compounds,quinolines

The highly enantioselective hydrogenation of quinoline derivatives is developed using [Ir(COD)Cl]2/(R)-MeO-Biphep/I2 system, and this methodology has been applied to the asymmetric synthesis of three naturally occurring alkaloids angustureine, galipinine, and cuspareine. This method provided an efficient access to a variety of optically active tetrahydroquinolines with up to 96% ee.     

Analysis of vasopressin using capillary electrophoresis with laser-induced fluorescence detector based on competitive immunoassay

A competitive immunoassay based on CE-LIF has been developed for the determination of vasopressin in biological mixtures. Vasopressin participates in the hormonal control of water metabolism and the constriction of arterioles in humans. Thus, detection of vasopressin is important in diagnosing pathological conditions and physiological water metabolism. The peptides were fluorescently tagged with FITC and purified by HPLC. The purified product was then mixed with the cerebrospinal fluid sample followed with the addition of anti-vasopressin antibody. It was possible to separate antibody-bound and free FITC-tagged vasopressin within 10 min by CE-LIF analysis using uncoated fused-silica capillary with high reproducibility.     

Boundary and particle number effects on the thermodynamic properties of trapped ideal Bose gases

The ideal noninteracting Bose gases trapped in a generic power-law potential in an any-dimensional space are studied. We present theoretical results of the corrections of thermodynamic properties due to finite particle number effects. The calculation uses the Euler-Maclaurin approximation to simplify the condensate fraction, and it also uses the Maslov index to discuss the boundary effect. Recently BEC (Bose-Einstein Condensation) has also been observed in a microelectronic chip; therefore, with a similar microstructure, we can obtain the effects of a rigid wall in a trap that have never been found before.Received: 3 January 2003, Published online: 23 July 2003PACS: 05.30.-d Quantum statistical mechanics     

Asymptotic limit for condensate solutions in the Abelian Chern-Simons Higgs model

In this paper we show that the maximal solutions in the Abelian Chern-Simons Higgs model on a 't Hooft type periodic domain converges to and is a harmonic map. We also study asymptotic behaviors of the energy density.

     

Asymptotic limit for condensate solutions in the Abelian Chern-Simons Higgs model II

In this paper we show that the maximal condensate solutions in the Abelian Chern-Simons Higgs model converge to in higher norms, where is a harmonic map.

     

Controlled Wild Algebras

The controlled wild algebra is introduced, a covering criterionfor a finite-dimensional algebra to be controlled wild is given,and this criterion is applied to the algebras with radical squarezero, algebras with zero relations, local algebras and finitep-group algebras. 2000 Mathematical Subject Classification:16G20, 16G60.