There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

J. Appl. Cryst.の発刊に際して

The Huisgen 1,3-dipolar cycloaddition reaction of organic azides and alkynes has gained considerable attention in recent years due to the introduction in 2001 of Cu(1) catalysis by Tornoe and Meldal, leading to a major improvement in both rate and regioselectivity of the reaction, as realized independently by the Meldal and the Sharpless laboratories. The great success of the Cu(1) catalyzed reaction is rooted in the fact that it is a virtually quantitative, very robust, insensitive, general, and orthogonal ligation reaction, suitable for even biomolecular ligation and in vivo tagging or as a polymerization reaction for synthesis of long linear polymers. The triazole formed is essentially chemically inert to reactive conditions, e.g. oxidation, reduction, and hydrolysis, and has an intermediate polarity with a dipolar moment of ∼5 D. The basis for the unique properties and rate enhancement for triazole formation under Cu(1) catalysis should be found in the high ∆G of the reaction in combination with the low character of polarity of the dipole of the noncatalyzed thermal reaction, which leads to a considerable activation barrier. In order to understand the reaction in detail, it therefore seems important to spend a moment to consider the structural and mechanistic aspects of the catalysis. The reaction is quite insensitive to reaction conditions as long as Cu(1) is present and may be performed in an aqueous or organic environment both in solution and on solid support.

Cu-catalyzed azide-alkyne cycloaddition.

As carbohydrates play a major role in numerous biological processes through their interactions with lectins and also appear as one of the most crucial post-translational modifications of proteins, chemists have developed several approaches for the design of glycoconjugates based on a series of conjugation methodologies. The recent development of copper(I)-catalyzed azide-alkyne cycloaddition (CuACC) paved the way to a novel conjugation strategy in which azido-functionalized carbohydrate derivatives can be readily connected to alkyne-functionalized (bio)molecules. This so-called "click chemistry" methodology has now found numerous applications both in chemistry and biology. The azido moiety can be introduced either directly at the anomeric carbon of the carbohydrate derivative, or attached to a spacer arm. We describe here the syntheses of 2,3,4,6-tetra-O-acetyl-β-D: -glucopyranosyl azide as well as 1-azido-3,6-dioxaoct-8-yl 2,3,4,6-tetra-O-acetyl-β-D: -galactopyranoside and 1-azido-3,6-dioxaoct-8-yl 2,3,6,2',3',4',6'-hepta-O-acetyl-β-D: -lactoside. These molecules can then be used in the construction of glycoconjugates to find applications in chemical biology.

Synthesis of azido-functionalized carbohydrates for the design of glycoconjugates.

Regioselective Protection at the Secondary Positions of Carbohydrates with Acyclic Protecting Groups

The present invention relates to a non covalent molecular structure comprising a carbon nanostructure and a pyrene based glycoconjugate (I) which is linked to the said carbon nanostructure by a non covalent link, the said glycoconjugate (I) having the formula : wherein B is a group which is present on any of the ten carbon atoms of the pyrene structure represented in ( I ) susceptible to bear a substituent, and is represented by the following group : -(CH2) n -CO-NH-A, wherein n is an integer from 1 to 9, A is a group of formula : The present invention also relates to an electronic device comprising the said non covalent molecular structure, and to the use of this device for the detection of a lectin involved in bacterial or viral infections. Thus the invention also relates to a method for detecting the presence of a lectin in a sample to be analysed.

Non covalent molecular structure, comprising a pyrene based glycoconjugate, device comprising the same and its use for detection of lectin

Protecting Groups at the Primary Position of Carbohydrates

2-Naphthyl-substituted glucopyranosylidene-spiro-oxathiazole prepared following a novel design principle was found to be the best known glucose analogue inhibitor of rabbit muscle glycogen phosphorylase b ( K i 160 nM).

Novel Design Principle Validated: Glucopyranosylidene-spiro-oxathiazole as New Nanomolar Inhibitor of Glycogen Phosphorylase, Potential Antidiabetic Agent.

Sébastien Vidal

Papers

Synthesis of azido-functionalized carbohydrates for the design of glycoconjugates.

Regioselective Protection at the Secondary Positions of Carbohydrates with Acyclic Protecting Groups

Non covalent molecular structure, comprising a pyrene based glycoconjugate, device comprising the same and its use for detection of lectin

Protecting Groups at the Primary Position of Carbohydrates

Novel Design Principle Validated: Glucopyranosylidene-spiro-oxathiazole as New Nanomolar Inhibitor of Glycogen Phosphorylase, Potential Antidiabetic Agent.