A fluorimetric determination of lecithin-cholesterol acyltransferase in blood plasma

A fluorimetric assay for lecithin-cholesterol acyltransferase in human plasma (normal and pathological) is described. The lowered cholesterol concentration in the enzyme reaction is determined fluorimetrically by using the cholesterol oxidase—peroxidase —tyramine system. The assay requires only 10 μl of plasma.     

An efficient chiral synthesis of (+)-sesbanine

(+)-Sesbanine was effectively synthesized from 4-methylnicotinonitrile and 1-malic acid.     

Differential pulse polarographic determination of l-lactate with a soluble enzyme preparation

Summary An electrochemical method for the determination of l-lactic acid using the specific reaction of lactate oxidase, has been studied and applied to lactic acid beverage and yoghurt. The technique is reasonably rapid and simple to perform. The calibration curve is linear in the concentration range from 1.0 to 20 mol/l, the reproducibility (R.S.D.) at 10 mol/l l-lactic acid is 1.34% (n=6) and the detection limit is 0.29 mol/l (k=2). The method can possibly be used for monitoring l-lactate or l-lactic acid in food industries and clinical laboratories.     

Memory effects on the quantum diffusion of a particle in a fluctuating medium

We introduce a phenomenological Hamiltonian for a particle in a medium with sitediagonal and off-diagonal disorder. Without assuming the usual white noise expression for the correlation between fluctuating variables, we arrive at a master equation using second order perturbation theory. This expression is expanded in powers of the correlation time. The mean square displacement and velocity are discussed and corrections to the diffusion coefficient are given.Partially supported by the grant of the Ministry of Education of the Japanese Government and by Sakkokai Foundation     

An asymmetric synthesis of cis,anti, cis-tricyclo[5,3,0,02,6]decanes applying γ-hydroxymethyl-γ-butyrolactone as a chiral synthon. First asymmetric total synthesis of (−)-β-bourbonene

The asymmetric total synthesis of cis, anti, cis-tricyclo[5,3,0,0^2,6]decane sesquiterpene β-bourbonene is described. The key (2+2) photocycloaddition was carried out applying the optically pure butenolide derivative $\text{6b}$ as a chiral synthon.     

Nanometric summation architecture based on optical near-field interaction between quantum dots

A nanoscale data summation architecture is proposed and experimentally demonstrated based on the optical near-field interaction between quantum dots. Based on local electromagnetic interactions between a few nanometric elements via optical near fields, we can combine multiple excitations at a certain quantum dot, which allows construction of a summation architecture. Summation plays a key role for content-addressable memory, which is one of the most important functions in optical networks.     

N-Boc-L-valine-connected amidomonophosphane rhodium(I) catalyst for asymmetric arylation of N-tosylarylimines with arylboroxines

A catalytic asymmetric arylation of sterically tuned imines with arylboroxines was developed by using N-Boc-l-valine-connected amidomonophosphane rhodium(I) catalyst in n-PrOH. The TMS group used for the steric tuning of imines is convertible to other functionalities that are applicable as a key foothold for the carbon-carbon bond-forming coupling reactions.     

Efficient synthesis of (±)-γ-lycorane employing stereoselective conjugate addition to nitroolefin

(±)-γ-Lycorane 3 was synthesized in 52% overall yield via seven steps from 5 by employing the highly stereoselective nitro-Michael cyclization of 5 to 9 and diastereoselective conjugate addition of aryllithium to a nitroolefin 10 as two key steps.     

Construction of arene-fused-piperidine motifs by asymmetric addition of 2-trityloxymethylaryllithiums to nitroalkenes: the asymmetric synthesis of a dopamine D1 full agonist, A-86929

The straightforward methodology for the construction of chiral arene-fused-piperidine motifs using a highly enantioselective addition of 2-trityloxymethylaryllithiums to cyclic and acyclic nitroalkenes has been developed. The versatility of the process was highlighted by the first asymmetric synthesis of a dopamine D1 full agonist, A-86929.