A New Monodisperse Reactive Resin with Active Groups on the Particle Surface

The cross-linked polymer beads with reactive groups as active supports have been widely used in many fields such as chromatographic separation, solid phase synthesis, catalytic reaction, ion exchange and adsorption etc. In resent years, the synthesis and application of monodisperse polymer beads with different structures have been rapidly developed1~4. It is obvious that this type of monosized resin as matrix of active supports will be even more advantageous in some applications. This paper pr…     

The Enantioselective Addition of Diethylzinc to Aldehydes Catalyzed by 2-Methylquinoline Derived Chiral Ligands

One of the most important and fundamental synthetic procedures for the establishment of a carbon-carbon bond stereoselectively is the enantioselective addition of organometallic reagents to aldehydes affording chiral secondary alcohols1. In this process, a frequently used method is to perform the reaction in the presence of a chiral ligand such as amino alcohol2. Here, we first report that two new chiral ligands3, which were readily available by the reaction of chiral ketone with lithiated 2-m…     

Synthesis of Pyridazinonethiadiazoles as Possible Antifungal Agents

Pyridazine derivatives represent one of the most active classes of compounds possessing a wide spectrum of biological activity. They are widely used in pharmaceuticals and agrochemicals1. On the other hands, 1,3,4-thiadiazole derivatives exhibit a broad spectrum of biological activity2-5. In view of these facts and in continuation of our interest in the chemistry of pyridazines, it was attempted to synthesize novel tri-heterocyclic compounds containing both pyridazinone and 1,3,4-thiadiazole m…     

Theoretical Studies on the Conformation of mono-6-O-p-nitrobenzoyl-β-cyclodextrin in Aqueous Solution

It is well known that a substituted cyclodextrin (CD) can often form a self-included complex, in which the substituent group is incarcerated into the CD cavity1. The phenomenon is interesting, as the self-inclusion is a nice model of protein folding2 and it has also been successfully used in the construction of various molecular devices3. Studies have showed that van der Waals force, hydrophobic effect, and electrostatic interaction are the major driving forces leading to the self-inclusion4…     

Microwave-assisted Polymerization of D,L-Lactide with Stannous Octanoate as Catalyst

Poly (lactic acid) (PLA) is an important member of the polyesters which are used as biomedical materials in bioresorbable suture, implantates and drug controlled release systems1. PLA is prepared by two routs2: ring-opening polymerization of dimeric cyclic lactide or direct polycondensation of lactic acid. The ring-opening polymerization has attracted much more scientific and industrial interests than the later one, but both methods need long time for the polymerization reactions to be compl…     

Synthesis and Photochemistry of Diphenylchlorin and Diphenylbacteriochlorin

5, 15-Diphenylporphyrin (DPP), a novel porphyrin model compound, was always inaccessible in quantities suitable for study1 because the difficulty of synthesis. So that the characteristic of this molecule had not been explored until a novel method developed for the preparation of DPP recently2. Therefore it will be possible for the synthesis of DPP-based photosensitizers, and investigation of their photodynamic properties. Here we reported the synthesis of novel photosensitizers 5, 15-diphe…     

The CH_3OH+Cl Hydrogen Abstraction Reactions: An ab initio Study

The hydrogen abstraction from methanol by atomic chlorine can proceed via two possible channels: CH3OH + Cl → CH2OH + HCl (i) → CH3O + HCl (ii)In 2000, Ahmed et al1. reported their investigation for the H abstraction dynamics of the CH3OH+Cl reaction by crossed molecular beams in conjunction with velocity map imaging. Hydroxymethyl (CH2OH) was detected in their experiments. In 1998, Jodkowski et al2. reported their theoretical study on the CH3OH+Cl reactions. They located inte…     

Study of Oxidation of Glutathione Treated with Hypochlorous Acid by Capillary Electrophoresis

Glutathione (GSH) protects human and animal's cells by the exchange with reversible oxidized glutathione (GSSG) when cells meet with oxidants, such as hydrogen peroxide (H2O2) and lipid peroxide. But when GSH meets with hypochlorous acid (HOCl), via the myeloperoxidase-catalysed oxidation of chloride by H2O2, the amount of GSSG formed does not account for all the GSH lost, which is quite different from that we has investigated in the reaction of GSH with H2O21. Prutz proposed the fo…     

Investigations of Thallium(Ⅰ) Underpotential Deposition on the Silver Rotating Disk Electrode and Its Analytical Application

Ｔｈａｌｌｉｕｍｉｓａｔｏｘｉｃｍｅｔａｌ.Ｂｅｃａｕｓｅｉｔｓｃｏｎｃｅｎｔｒａｔｉｏｎｉｎｅｎｖｉｒｏｎｍｅｎｔａｌａｎｄｂｉｏｌｏｇｉｃａｌｓａｍ ｐｌｅｓｉｓｉｎｔｈｅ 1ｎｇ/ｇｒａｎｇｅｏｒｌｅｓｓ[1] ,ｉｔｉｓｄｉｆｆｉｃｕｌｔｔｏｄｅｔｅｒｍｉｎｅｔｈｅｍｅｔａｌｂｙｕｓｉｎｇｃｏｎｖｅｎｔｉｏｎａｌｅｌｅｃｔｒｏａｎａｌｙｓｉｓｍｅｔｈｏｄｓ .Ｄｉｆｆｅｒｅｎｔｉａｌｐｕｌｓｅａｎｏｄｉｃｓｔｒｉｐｐｉｎｇｖｏｌｔａｍｍｅｔｒｙ(ＤＰＡＳＶ )ｉｓａｓｅｎｓｉｔｉｖｅｍｅｔｈｏｄｆｏｒ…     

Synthesis of 5-Substituted-3-[(2’R,4’R)-4’-Hydroxy-2’-hydroxymethyltetrahydrofuran-4’-yl]-1,2,4-oxadiazoles and Their Epimers

The syntheses of 5-substituted-3-[( 2' R, 4' R)-4 ' -hydroxy-2 ' -hydroxymethyltetra-hydrofuran-4' -yl]D-1 ,2, 4-oxadiazoles and their epimers were accomplished with the aid of th construction of 1,2, 4-oxadiazoles by condensation of O-acylated cyanohydrins with hydroxylamine via intramolecular transacylation and subsequent cyclization.