烯丙基作为保护基在修饰寡核苷酸合成中的应用

研究了烯丙基作为核苷糖环羟基保护基在寡核苷酸及其类似物的合成中应用的可能性。烯丙基保护基可用PdCl2在温和条件下脱除,适合应用于对碱不稳定的寡核苷酸的合成。应用烯丙基保护基成功地合成了三胸苷二碳酸酯和二胸苷亚硫酸酯。     

多羟基化合物水溶液渗透系数的测定

The determination of the osmotic coefficients of the aqueous solution of polyhydroxylated compounds such as glycol, glycerol, sucrose and glucose by Vapour Pressure Osmometry at 313, 323 and 333K was carried out over the concentration range of 0.0-2.1mol﹒kg-1 and 0.0-2.0 mol﹒kg-1 respectively. By using a linear least-square fitting routine, the osmotic coefficients were fitted by a simple polynomial equation, It was found that the relation between the experimental results of molal osmotic coefficients Φ and the mass molal concentration of the solution m are in agreement with that from the polynomial fitting at different temperature. Factors which influence the osmotic coefficient such as the number of hydroxyl of polyhydroxylated compounds or the molecule weight of the solute molecules should be further studied, this work will also contribute to the studies of other thermodynamical properties of the aqueous solution of polyhydroxylated compound.     

硼酸与多羟基化合物的反应及硼选择性树脂

本文综述了硼酸与多羟基化合物的反应，并系统介绍了硼选择性树脂的发展，引用文献５７篇。     

二茂基镧系8—羟基喹啉化合物的合成及其热稳定性研究

通过三茂基镧系化合物Cp_3Ln(Cp=C_5H_5;Ln=Sm,Dy,Ho)与8-羟基喹啉反应(HL),合成了3种新的镧系金属有机化合物,通式为Cp_2LnL(Ln=Sm,Dy,Ho)。经元素分析、红外光谱、X光电子能谱、质谱及分子量测定,推断化合物具有二聚体结构,分子内存在通过喹啉氮原子和氧原子与金属配位而形成的五元螯合环。对化合物的热稳定性进行了研究和比较,发现化合物Cp_2SmL对热不稳定,在180℃以上分解为Cp_3Sm和SmL_3。     

以烯丙基作为核苷中糖羟基保护基的研究

对烯丙基作为核苷糖环上羟基保护基进行了研究.烯丙基可用于核糖羟基的保护,用PdCl₂可脱除核苷糖环上烯丙基,保护及脱保护都很简便.PdCl₂还可脱除核苷糖环5'-OH常用的保护基--对甲氧基三苯甲基及二对甲氧基三苯甲基.控制适当的条件,PdCl₂既能够选择性地脱除对甲氧基三苯甲基或二对甲氧基三苯甲基,又可同时脱除保护糖环羟基的烯丙基.     

3—磺基—4—羟基香豆素希土化合物的合成及性质

在不同条件下制得三种类型的希土与3-磺基-4-羟基香豆素(H₂SHC)化合物,元素分析确定了它们的组成分别为Ln(HSHC)₃·9H₂(Ln=La,Pr,Nd,Gd,Dy,Er,Yb,Y),Ln₂(SHC)₃.nH₂O(Ln:La,Pr,Nd,Sm,Gd,N:4或6)和Na₃Ln(SHC)₃·H₂O(Ln=Er,Yb).并通过它们的摩尔电导戌\重,溶解度,红外光谱和电子吸收光谱对各种化合物进行了结构和性质的研究。     

RNA化学合成中的保护基

近几年来, RNA的化学合成有了较大进展, 本文讨论了RNA化学合成过程中的保护基问题,着重介绍了核糖核苷的2'-和3'-位羟基的选择性保护方法。     

硼酸与多羟基化合物配位反应的热化学研究

用量热法在298.2 K测定了B(OH)~-_4与多羟基化合物的反应焓。计算了硼酸与多羟基化合物的配位焓和配离子的标准生成焓。根据配位焓确定了B(OH)~-_4与甘露醇、山梨醇、丙三醇、葡萄糖等多羟基化合物配位反应的配位数，B(OH)~-_4与甘露醇、山梨醇的配位数是2；与丙三醇、葡萄糖的配位数是1．     

催化选择转化多羟基化合物制备高附加值化学品研究进展

对近年来催化转化多羟基化合物制备5-羟甲基糠醛、乙二醇、1,2-丙二醇、1,3-丙二醇等高附加值化学品进行了综述. 分析了果糖、葡萄糖、纤维素等不同结构的碳水化合物制5-羟甲基糠醛存在的挑战, 并对相应的解决方法进行了总结. 对于5-羟甲基糠醛的转化, 我们重点讨论了5-羟甲基糠醛选择性氧化制备2,5-二甲酰基呋喃和2,5-呋喃二甲酸以及它们作为聚合单体的潜在应用. 概述了催化氢解纤维素、糖醇、甘油等多羟基化合物制备乙二醇、1,2-丙二醇、1,3-丙二醇等二元醇的方法, 并对可能的机理进行了讨论. 依据近年来多羟基化合物催化选择性转化制备高附加值化学品的研究现状, 对今后的研究热点进行了展望.     

A NEW POLYMER-BOUND 1,2-DIOL AS A PROTECTING AGENT FOR SYMMETRICAL DIALDEHYDE

A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chloro-1,2-propanediol in the presence of a phase transfer catalyst, n-tetrabutylammonium iodide. The capacity of resin 6 for terephthaidehyde reached 1.43 mmol/g. The aldehydic groups attached to polymer 6 reacted with hydroxylamine hydrochloride or reduced by sodium borohydride giving p-formylbenzaldoxime (yield: 89%)and p-formyl-benzalcohol (yield: 734%), respectively. The high yields of these polymer-supported reactions showed that the polymer 6 possessed the effective isolation of its reactive sites.     

EVALUATION OF THE N-PHTHALOYL MOIETY AS PROTECTING GROUP IN AMINOACYLPHOSPHONIC DERIVATIVES

Abstract

Reaction of dimethyl benzoylphosphonate with hydrazine hydrate gave exclusively benzhydrazide. Reaction of methyl lithium benzoylphosphonate with hydrazine hydrate gave the corresponding hydrazone (3) as a 65:35 mixture of E and Z isomers. Reaction of hydrazine hydrate with diisopropyl 4phthalimidobutanoylphosphonate gave mainly products resulting from nucleophilic attack of hydrazine on the carbonyl of the acylphosphonate and only a small percentage of phthalhydrazide. From our results it appears that the N-phthaloyl protecting group is not suitable for the transient protection of amino groups during attempts to synthesize aminoacylphosphonates.     

竞争型三元配合物生成热的量热测定 镍(II)-草酸-甘氨酸三元体系

我们曾经报导过铜(Ⅱ)-草酸-乙二胺三元竞争体系的量热研究。由于铜(Ⅱ)离子的配位数为4。对两个二齿配体(草酸和乙二胺)来说,混配络合物只有一种(MAB)。然而对于(钅臭)(Ⅱ)-草酸-甘氨酸的三元体系来说,情况就较复杂。有三种混配络合物(MAB,MA_2B,MAB_2)的生成反应必须考虑,所以在热效应计算上就更加复杂,至今尚无文献报道。本文试图建立一种合理的数据处理方法以计算这样复杂体系的热效应。数学处理和实验     

2-DICHLOROMETHYL-1,3-DIOXOLAN-2-YL ORTHOESTERS. A POTENTIAL PROTECTING GROUP FOR SUGAR DERIVATIVES

Reactions of 2-dichloromethylene-1,3-dioxolane (2) with acetal protected sugar derivatives in neutral media gave 2-dichloromethyl-1,3-dioxolan-2-yl orthoesters. These orthoesters are readily hydrolysed under mild acidic conditions offering a new method for the preparation of readily removable protecting groups. This strategy was realised in the preparation of 6-O-acetyl-3,5-di-O-methyl-1,2-O-isopropylidene-α-d-glucofuranose.     

催化剂和供氢剂对渣油模型化合物裂化反应选择性的影响

供氢剂与分散性催化剂协同作用对于传统的煤液化体系和渣油加氢裂化体系非常重要。通过活化分子氢及煤分子，使液化反应在较低的温度下进行以减少副反应，继而提高氢转移效率，增加液体产物产率。供氢剂和催化剂起促进煤分子裂化的作用。将供氢剂与催化剂的协同作用应用于渣油加     

APPLICATION OF THE SULFONATE ESTER GROUP AS A LINKER FOR SOLID PHASE ORGANIC SYNTHESIS

A use of sulfonate ester as a linker in synthesis of w-aminoalkanols was reporte.Diols were tethered onto polystyryl sulfonyl chloride resin,yielding sulfonate resins(2).After cleaved by diethyl amine,diisopropylamine and propylamine respectively,three w-aminoalkanlos were obtained.     

APPLICATION OF THE SULFONATE ESTER GROUP AS A LINKER FOR SOLID PHASE ORGANIC SYNTHESIS

1. INTRODUCTIONIn recent years, solid phase organic synthesis (SPOS) has been increasingly used in the synthesis of small organic molecules [1]. The rapid development of SPOS brings with it the need for expanding a variety of linkers in order to accommodate new synthesis methods[2], and especially in the case of combinatorial chemistry, to allow additional diversity elements.Recently, Rueter and coworkers reported the use of a sulfonate ester as a linker in SPOS [3,4] and the compati…     

USE OF AN ISOPROPYL ESTER MOIETY AS A SULFONIC ACID PROTECTING GROUP IN A GREATLY IMPROVED SYNTHESIS OF AN ARYLSULFONIC ACID-BASED FOLLICLE STIMULATING HORMONE ANTAGONIST

ABSTRACT

A sulfonic acid isopropyl ester protecting group methodology was developed that allowed for the efficient seven step synthesis of multigram amounts of an arylsulfonic acid-based follicle stimulating hormone antagonist.     

FLAVIN COMPOUNDS AS AGENTS FOR THE OXIDATION OF PLASTOCYANIN IN BLUE LIGHT

Abstract—Flavins, flavin nucleotides and selected flavoproteins have been compared in a reaction using blue light. in which plastocyanin is oxidized as the flavin is photoreduced. Per unit of light absorbed. flavin mononucleotide is more effective than flavin adenine dinucleotide, ribotlavin or lumiflavin. Of the flavoproteins tested, diaphorase from Clostridium kluyveri was most effective, but was less active than free flavin mononucleotide. The oxidation of plastocyanin requires aerobic conditions. and appears to be mediated by the production of singlet oxygen when the flavin is irradiated.