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1.
徐峰  万晓龙  王军锋  康经武 《色谱》2016,34(1):57-61
建立了4个单手性和3个双手性(含有手性中心和面手性)的二茂铁衍生物在Chiralpak IC(纤维素-三(3,5-二氯苯基氨基甲酸酯))和Chiralpak IE3(直链淀粉-三(3,5-二氯苯基氨基甲酸酯))手性固定相上的高效液相色谱分离方法。4个单手性二茂铁衍生物中有3个可以在Chiralpak IE3固定相上实现基线分离,另外1个则在Chiralpak IC手性固定相上实现基线分离。3个双手性二茂铁衍生物可在Chiralpak IC手性固定相上实现基线分离。研究表明,这两种手性固定相对二茂铁衍生物具有较好的手性识别作用,并且具有互补作用。这一研究结果可为手性二茂铁化合物的分离提供借鉴和参考。  相似文献   

2.
In this study, a series of coumarin derivatives were synthesized and their inhibitory effects on the activity of mushroom tyrosinase were evaluated. As a result of measuring the inhibition of tyrosinase activity of these derivatives, the compounds 3e (1.05 μM), 3f (0.83 μM), 3h (0.85 μM), 3i (1.05 μM), and 3k (0.67 μM) of the geranyloxycoumarin derivatives were highly active at a concentration of 0.8%. The geranyloxycoumarin derivatives exhibited better activity than the hydroxycoumarin derivatives. Among the geranyloxycoumarin derivatives, compound 3k was two times more active than arbutin, a positive control, at a concentration of 0.4%. The above results suggest that geranyloxycoumarin derivatives have great potential for application as functional cosmetic ingredients with tyrosinase-inhibiting activity.  相似文献   

3.
This article covers precise syntheses of well‐defined chain‐end and in‐chain functionalized polymers, multi‐functionalized polymers with a definite number of functional groups, star‐branched and graft polymers by recently developed methodologies using specially designed 1,1‐diphenylethylene (DPE) derivatives. The DPE derivatives include various substituted DPE derivatives with functional groups and their derivatives, DPE‐functionalized DPE derivatives, and well‐defined DPE‐functionalized macromonomers. The synthetic utility and importance of these DPE derivatives are described via such polymer syntheses.  相似文献   

4.
As an antitumor drug, because of its low efficacy and high toxicity, several modifications have been made on 5-fluorouracil (5-Fu). Some compounds have been found to be highly efficient and much less toxic for the treatment of various solid tumors1~4. Among them, deoxyfluridine (Furtulon) has been used clinically for several years. In our previous work, we have prepared several substituted derivatives of 5-Fu and the primary result shows that some of them have certain antitumor activity5,6. …  相似文献   

5.
3-Cyanomethylidene oxindole derivatives were prepared in excellent yields utilizing DBU-promoted Knoevenagel condensation of isatin derivatives with active methylene reagents. The isolated products were then reacted with azaenamines via a DBU-promoted Michael addition to yield spirocyclic 2-oxindole derivatives with incorporated 6-amino-4H-pyridazines and their fused derivatives.  相似文献   

6.
Summary Phenylamino-propanediols were analysed by capillary gas chromatography as various derivatives. Trimethylsilyl and methylboronic acid derivatives were detected with a FID. The trifluoroacetyl derivatives were analysed using an ECD. The structure of the derivatives was confirmed by GC-MS. Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984  相似文献   

7.
通过糖单元6-位羟基的保护和去保护,运用区域选择性方法合成了6种新型多糖类氨基甲酸酯衍生物,分别为纤维素/直链淀粉-[2,3-二(3,5-二甲基苯基)-6-环己基]氨基甲酸酯、[2,3-二(3,5-二氯苯基)-6-环己基]氨基甲酸酯及[2,3-二(4-氯苯基)-6-环己基]氨基甲酸酯,并将其涂敷在氨丙基硅胶的表面制备HPLC手性固定相.利用1H-NMR与FTIR光谱技术对所合成衍生物进行结构表征和分析,并应用HPLC法评价其对于9种手性化合物的手性识别能力.通过与以手性识别能力高而著称且含有单一取代基的纤维素/直链淀粉-三(3,5-二甲基苯基氨基甲酸酯)等手性固定相的对比分析表明,所合成新型手性固定相对于某些对映体显示出更优的手性识别能力.由进一步分析表明,糖单元2-、3-和6-位取代基的性能对于纤维素和直链淀粉氨基甲酸酯类衍生物的手性识别能力均具有较大影响.  相似文献   

8.
Anodic fluorination of 3-substituted benzofuran derivatives in a variety of fluoride salts resulted in the formation of three fluorinated products; two stereoisomers of 2,3-difluoro-2,3-dihydrobenzofuran (cis and trans) and cis-2-fluoro-3-hydroxy-2,3-dihydrobenzofuran derivatives. Dehydrofluorination of the main products, cis-difluoro derivatives, furnished the nonaromatic 2-fluoro-3-benzofuranyledene derivatives instead of the aromatic 2-fluorobenzofuran derivatives.  相似文献   

9.
Several triazonine-carbaldehyde derivatives have been prepared using different protocols; however, some require special reagents and conditions. The aim of study involved the synthesis of two triazonine-carbaldehyde derivative using testosterone or OTBS-testosterone as chemical tool. Triazonine-carbaldehyde derivatives were prepared by a series of reactions that involve the following: (1) synthesis of two nitrobenzamide derivatives by reaction of testosterone or OTBS-testosterone with p-nitrobenzoyl azide using Copper(II) as catalyst; (2) reaction of the nitrobenzamides with ethylenediamine to form two triazonine derivatives using boric acid as catalyst; (3) preparation of hexynyl-triazonine derivatives by the reaction of two triazonines 6-chlorohex-1-yne in basic medium; (4) reaction of hexynyl-triazonine derivatives with benzaldehyde to form two triazoninol analogs; (5) preparation of triazoninynal derivatives through oxidation of triazoninol analogs with dimethyl sulfoxide; and (6) synthesis of triazonine-carbaldehyde derivatives by the reaction of triazoninynal derivatives with hexyne-1 using Copper(II) as catalyst. The chemical structure of compounds was determined by spectroscopic and spectrometric methods. In conclusion, in this work were prepared two triazoninone derivatives using several chemical techniques, which are simple procedures and easy to handle.  相似文献   

10.
A simple method is described for the preparation of dextran-linked coenzyme derivatives. Several different 8-(6-aminohexyl)amino-adenine nucleotide coenzymes and their derivatives were covalently attached to dextran by incubation with bromohydroxypropyl derivatives of dextran at room temperature in an alkaline medium. The polymer-linked adenine nucleotide derivatives were separated from the free coenzyme derivatives by a Sephadex G-50 column. The prepared dextran derivatives have ligand densities ranging from 20 to 100 μmol/g of dextran derivatives depending on the conditions of coupling and derivatives. NMR studies revealed that proton resonances of the polymer-linked coenzymes exhibit short transverse relaxation times (T2) but long longitudinal relaxation times (T1) This phenomenon was interpreted in terms of the anisotropic motions of the dextran-bound coenzyme derivatives in which the fast axial motions and slow restricted transverse motions of the bound coenzyme derivatives are postulated. These observations could properly explain why the polymer-linked coenzymes exhibit lower biological activity, but similar binding affinity to most enzymes.  相似文献   

11.
A series of 2-phenylbenzofuran derivatives with a carbamoyl, alkylamino, or alkyloxy group at the 5 or 6 position of the benzofuran ring were synthesized and evaluated for rat and human testosterone 5 alpha-reductase inhibitory activities in vitro. Against rat enzyme, the carbamoyl derivatives had more potent inhibitory activities than the alkylamino or alkyloxy derivatives, and the 6-carbamoyl derivatives tended to be more potent than the 5-carbamoyl derivatives. Against human enzyme, the 6-substituted derivatives had more potent inhibitory activities than the 5-substituted derivatives. The 6-carbamoyl and 6-alkylamino derivatives tended to show stronger inhibitory activities against human type 1 enzyme than against type 2 enzyme, but they were not largely selective.  相似文献   

12.
The results obtained from a study on the stereochemical control in the dihydroxylation of the double bond of vinyl epoxides and their derivatives (bromo derivatives, azido derivatives and vinyl aziridines) are presented herein. A significant diastereoselectivity was observed for the bromo derivatives, azido derivatives and N-protected vinyl aziridines, whereas vinyl epoxides and unprotected vinyl aziridines showed no diastereoselectivity. The results obtained are generally consistent with the Kishi model.  相似文献   

13.
汪钢强  孙绍发  吴鸣虎  汪秋安 《合成化学》2016,24(11):1005-1020
综述了以苯胺衍生物(或硝基苯衍生物)为原料合成吲哚衍生物的方法和吲哚衍生物的应用。吲哚类化合物的合成方法主要有:Fischer合成法,苯胺衍生物合成法,硝基衍生物合成法和Nenitzescu合成法等。吲哚衍生物在制药、染料和香料等领域有重要应用。参考文献105篇。  相似文献   

14.
A convenient method for the preparation of symmetric and unsymmetric bisimidazole derivatives was established. The symmetric bisimidazolylmethane derivatives 1a–9a was prepared with 2‐substituted imidazole derivatives 1–9 as reaction materials. However, the symmetric and unsymmetric bisimidazolylmethane derivatives 10a–12a and 10b–12b was obtained, respectively. With 4‐position with the azo‐groups imidazole derivatives 10–12 were used as reaction materials. All these compounds have been structurally characterized by the NMR, ESI‐MS, and EA. And 8a and 12a were also characterized by the X‐ray single crystal diffusion.  相似文献   

15.
Imidazolecarboxamide derivatives have been known to exhibit biological activity, especially antiparasitic activity.1 To date imidazole-4(5)-monocarboxamide derivatives and symmetrical imidazole-4,5-dicarboxamide derivatives have been investigated.1 However, unsymmetrical imidazole-4,5-dicarboxamide derivatives, having different carboxamide groups, have not been investigated. Therefore, the author was prompted to devise a synthetic method for unsymmetrical diamide derivatives.  相似文献   

16.
在简要介绍了Langmuir-Blodgett (LB)膜的基础上, 主要依据制备LB膜的四硫富瓦烯(TTF)衍生物化学结构的不同, 概括了基于两亲性TTF衍生物、非两亲性TTF衍生物、TTF电荷转移(CT)复合物或盐、以及TTF金属络合物LB膜的制备、结构表征与性能研究进展. 介绍了基于TTF衍生物的LB膜在导电、化学及生物传感器、光学以及磁性方面的应用, 并对基于TTF衍生物LB膜的发展进行了展望.  相似文献   

17.
Cloud point extraction was successfully applied to the preconcentration of phenothiazine derivatives, such as pericyazine (PC), chlorpromazine (CP) and fluphenazine (FUL), for gas chromatography (GC). Phenothiazine derivatives were separated from surfactants by passing the surfactant-rich phase through a cation exchange column after cloud point extraction, permitting the determination of the phenothiazine derivatives extracted in the surfactant-rich phase by GC. The optimal condition for the cloud point extraction of phenothiazine derivatives was also investigated using Triton X-100, Triton X-114, and PONPE10. Triton X-114 provided the most efficient recovery of phenothiazine derivatives among the surfactants used. The addition of sodium chloride and excess ammonia to the sample solution resulted in a decrement of the recovery of the phenothiazine derivatives. The proposed method was applied to the determination of phenothiazine derivatives in spiked human serum by GC. The recoveries of PC, CP, and FUL in spiked human serum were 95.1%, 87.1%, and 84.7%, respectively.  相似文献   

18.
双组分有机低分子凝胶的研究已成为纳米化学新兴研究领域的热点之一, 形成双组分有机低分子凝胶的有机分子具有多种结构, 例如: 巴比妥酸衍生物、氨基酸衍生物、糖类衍生物、金属有机化合物、胆固醇类衍生物和树枝状分子等. 较系统地综述了目前已知的双组分凝胶及其所涉及的有机低分子凝胶因子的主要结构类型, 并展望了双组分有机低分子凝胶的应用前景.  相似文献   

19.
Silica sulfuric acid (SSA) mediated synthesis of naphtho[2,1-b]furan derivatives starting from β-nitrostyrene derivatives and β-naphthol derivatives under solvent-free conditions have been developed. The scope of SSA as a heterogeneous catalyst is extended to one-pot multicomponent reaction for the synthesis of functionalized pyrazole derivatives under solvent-free conditions from readily available β-nitrostyrene derivatives, acetyl acetone, and hydrazine hydrate. The synthetic methods have significant advantages such as solvent-free conditions, simple operation, shorter reaction times, ease and clean isolation procedures, and very good yields of products.  相似文献   

20.
Thirteen novel NO-releasing derivatives of betulinic acid (BA) bearing two types of NO-donors (nitrates and furoxans) were synthesized and evaluated for their antitumor activity. The results showed that furoxan-based derivatives exhibited higher antitumor activity than nitrate-based derivatives, with compounds 11a and 11b displaying promising potency against B16 cell lines and HepG2 cell lines (IC50 < 1 μmol/L). Wesupposed that NO-releasing amount of these derivatives which can be detected by Griess method may contribute more to their antitumor activity. As a result, furoxan-based derivatives released larger amount of NO than that of nitrate-based derivatives, which partially explained the higher anti-tumor activity of the former.  相似文献   

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