Solid phase synthesis of aromatic isophthalic oligoamides with controlled molecular weight

The synthesis of oligo(hexafluoroisopropylidene isophthalamide) on a solid support of SynPhase™ Lanters is described. The repetitive coupling steps using symmetrical diamines and diacid chlorides allows to obtain aromatic oligoamides with controlled molecular weight ( = 5480 g/mol) and narrow molecular weight distribution (PDI = 1.03) as evidenced by gel permeation chromatography. Moreover, the FTIR and ¹H NMR analysis demonstrated their chemical nature and OH-end groups functionality. The thermal properties of aromatic oligoamides were found to be lower, as expected, than those of poly(hexafluoro-isopropylidene isophthalamide), the same repeating unit high molecular weight polyamide, as judged by differential scanning calorimetry and thermogravimetrical analysis.     

Synthesis of N′-substituted Ddz-protected hydrazines and their application in solid phase synthesis of aza-peptides

Hydrazine derivatives are of considerable scientific and industrial value. Substituted hydrazines are precursors for many compounds of great interest and importance, among them aza-peptides. (Aza-peptides are peptide analogues in which one or more of the α-carbons, bearing the side chain residues, has been replaced by a nitrogen atom.) Aza-amino acid residues conserve the pharmacophores necessary for biological activity while inducing conformational changes and increased resistance to proteolytic degradation. These properties make aza-peptides attractive tools for structure-activity relationship studies and drug design. We describe the synthesis of N′-substituted 2-(3,5-dimethoxyphenyl)propan-2-yloxycarbonyl (Ddz) protected hydrazines. A general approach for solid phase synthesis of aza-peptides has been developed based on the in-situ activation of the N-Ddz,N′-substituted hydrazines with phosgene, followed by introduction to the N-terminus of a resin-bound peptide. The Ddz-aza-amino building units include aliphatic, aromatic and functionalized side chains, protected for synthesis by the Fmoc strategy. Solid phase aza-peptide synthesis is demonstrated including selective mild deprotection of Ddz with Mg(ClO₄)₂ and coupling of the next amino acid with triphosgene. Ddz deprotection is orthogonal with the Fmoc and Boc protecting groups, making the solid phase Ddz-aza-peptide synthesis compatible with both the Fmoc and the Boc strategies. The Ddz-protected hydrazines have wide applications in the synthesis of substituted hydrazines and in the synthesis of aza containing peptidomimetics.     

糖肽的固相合成

综述了固相法合成糖肽的最新进展，论述了合成策略和所用聚合物载体，这是一种很有前途的合成糖肽的方法，参考文献４２篇。     

Solid phase synthesis of an extensively focused library of thiadiazole ethers

An approach to combine the advantages of random and of focused combinatorial libraries in pharmaceutical research is described with the example of a solid phase synthesis of 2,5-disubstituted thiadiazole ethers. Key steps of synthesis are the introduction of the heterocycle by selective, sequential nucleophilic double substitution of 2,5-bis(methylsulfonyl)-1,3,4-thiadiazole and the oxidation of the benzylsulfanyl-1,3,4-thiadiazole to the corresponding sulfone using MCPBA on solid phase.     

固相有机合成

综述了近年来固相有机合成中采用的连接分子和连接策略及固相合成在有机合成中的应用。     

Solid phase synthesis of mono- or disubstituted arginine containing peptides from an isothiocitrulline precursor

A method for the solid phase synthesis of substituted arginine containing peptides starting from an isothiocitrulline precursor is described. In this procedure, a peptide containing one or more protected ornithine residue(s) was assembled on a solid support. Following selective deprotection, ornithine residue(s) was (were) converted into S-methyl-isothiocitrulline in three steps. Subsequent reaction with primary or secondary amines afforded mono and disubstituted arginine-containing derivatives, respectively. Using lysine instead of ornithine afforded substituted homoarginine-containing derivatives.     

Solid phase extraction of amines

The objective of this paper is to provide information about solid phase extraction (SPE) as an alternative to liquid-liquid extraction of amines from several matrices. Different sorbents ranging from non-polar phases, such as C₁₈ silica to more polar such as cyanopropylsilica (CN) have been tested for analysis of aliphatic amines as monoamines, diamines and polyamines. Phenylalkylamines such as amphetamine or methamphetamine and heterocyclic amines such as histamine or cephalosporins (which also contain a carboxylic group), have also been studied. The different steps involved in the extraction procedure have been tested (conditioning, retention, pre-concentration, washing and elution) in order to obtain extracts free of interferences and enough sensitivity. C₁₈ silica (100 mg) was selected as optimal phase with recoveries nearly of 100%. The elution of more polar amines was performed in acidic conditions while less polar amines required organic solvents. Cephalosporin retention was performed in acid condition by using disk cartridges EM C_18, which gave better selectivity. The optimised clean-up procedures have been discussed to the quantification of the corresponding amines in real samples (urine, water and beer). The accuracy and precision were outlined.     

Solid phase synthesis of N-aminodipeptides in high optical purity

N-Aminodipeptide derivatives can be easily prepared with high optical purity on solid phase via a Mitsunobu protocol between a solid supported α-hydroxyacid and a free phthaloylated α-Z-N-aminohydrazide.     

固相同步多重肽合成

本文综述了近十年来在固相肽合成基础上发展的各种同步多重合成新技术。它们的应用可进一步提高肽合成的效率、降低成本,并将促进许多肽的结构-活性关系研究。因此,将对激素-受体间作用的机理研究、对分子免疫学的发展及研究新的肽类诊断试剂或疫苗均可创造较好的条件。     

Solid phase synthesis of a molecular library of pyrimidines, pyrazoles, and isoxazoles with biological potential

A small molecular library of 40 pyrimidine, pyrazole, and isoxazole derivatives, bearing structural features for a promising binding of therapeutically interesting enzymes, was designed and prepared. An efficient and straightforward solid phase synthesis was envisaged and carried out on a Rink amide resin. The assistance of microwave heating in any step reduced the reaction time, increased the reaction yields, and allowed an easy work-up and purification of the targeted compounds.     

固相反射分光光度法测定镍的研究

提出了固相反射分光光度法，并以Ｎｉ（Ⅱ）丁二酮肟ＴｒｉｔｏｎＸ１００体系为例拟定了测镍的固相反射光度法。方法简便、快速、灵敏，检测限为０．０２９ｍｇ·Ｌ１，精密度好（测定２５μｇ镍１１次，ＲＳＤ＝１．１％）。     

Solid phase total synthesis of callipeltin E isolated from marine sponge Latrunculia sp.

Solid phase total synthesis of callipeltin E (1), truncated linear peptide isolated from marine sponge, Latrunculia sp. was achieved. Our strategy based on traditional Fmoc-SPPS was in common use TFA-treatment final deprotection to reach callipeltin E (1) contained acid-sensitive βMeOTyr.     

低聚糖的固相合成与反应机理研究进展

对低聚糖的固相合成作了评述，重点介绍了聚合物载体对糖苷化反应的影响、羟基的保护（包括载体化保护基）、糖苷化反应的各种方法和偶联过程中的立体控制问题。     

Solid phase deprotection of 2-nitrobenzenesulfonamides: synthesis of simple 2-(alkylamino)-pyrroles

The 2-nitrobenzenesulfonamide cleavage using a solid-phase thiophenolate reagent gives simple 2-(alkylamino)-pyrroles without the presence of the competing nucleophilic substitution product.     

固相有机合成小分子化合物库

从杂环化合物库和非杂环化合物库两方面介绍了组合化学中采用固相合成技术所构建的小分子化合物库。     

Solid phase extraction of metal ions using carbon nanotubes

The sorption behaviour of carbon nanotubes (CNTs) toward some divalent metal ions such as Cu(II), Co(II), Ni(II), Zn(II), Pb(II), Mn(II) and Cd(II) has been investigated systematically. The affinity order of the metal ions towards CNTs at pH in the range of 7.0-9.0 was: Cu(II) > Pb(II) > Zn(II) > Co(II) > Ni(II) > Cd(II) > Mn(II). The experimental parameters for preconcentration of copper, which exhibits the highest affinity towards carbon nanotubes, on a microcolumn packed with CNTs prior to its determination by flame atomic absorption spectrometry have been investigated. Copper can be quantitatively retained at pH 8.2 from sample volume up to 150 mL and then eluted completely with 0.1 mol L^− 1 HNO₃. The limit of detection limit for Cu(II) determination with FAAS detection was 2.1 μg L^− 1, and the RSD was 3.5% at the 50 μg L^− 1 level. Under the optimal conditions for copper enrichment also Zn(II), Pb(II) and Ni(II) could be quantitatively preconcentrated from water samples. The method was validated using a certified reference materials BCR-610 and SRM 1640.     

芳亚甲基丙二腈、芳亚甲基氰乙酰胺的固相合成

芳醛和丙二腈、氰乙酰胺在NH4Ac催化下经固相反应高产率的得到芳亚甲基丙 二腈和芳亚甲基氰乙酰胺。     

Cystine mimetics--solid phase lanthionine synthesis

The total solid phase synthesis of an analogue of the B ring of nisin was achieved, in a biomimetic fashion, via the solid phase diastereoselective cyclisation of a dehydrothiol-containing peptide.     

Solid phase micro-extraction coupled with ion mobility spectrometry for the analysis of ephedrine in urine

Quantitative solid phase micro-extraction (SPME) coupled with ion mobility spectrometry is demonstrated using the analysis of ephedrine in urine. Since its inception in the 1970's ion mobility spectrometry (IMS) has evolved into a useful technique for laboratories to detect explosives, chemical warfare agents, environment pollutants and, increasingly, for detecting drugs of abuse. Ephedrine is extracted directly from urine samples using SPME and the analyte on the fiber is heated by the IMS desorber unit and vaporized into the drift tube. The analytical procedure was optimized for fiber coating selection, extraction temperature, extraction time, sample pH, and analyte desorption temperature. The carryover effects, ion fragmentation characteristics, peak shapes, and drift times of ephedrine were also evaluated based on the direct interfacing of SPME to IMS. A limit of detection of 50 ng/mL of ephedrine in urine and a linear range of 3 orders of magnitude were obtained, showing that SPME-IMS compares well to other techniques for ephedrine and drug analysis presented in the literature.     

Solid phase synthesis of peptide-siRNA conjugates containing disulfide bond unit

A disulfide-modified nucleoside was designed and synthesized. After loading the modified nucleoside on controlled pore glass (CPG), solid phase synthesis strategy was used to prepare peptide-oligonucleotide conjugates (N-3') containing disulfide bond unit. The 3'-sense strand peptide-siRNA conjugate (Ⅶ) maintained good gene silencing activity, while that of the 3'-antisense strand conjugate decreased somewhat. And the sense strand off-target effect of Ⅶ decreased remarkably.