Copper‐Catalyzed Efficient Multicomponent Reaction: Synthesis of Benzoxazoline‐Amidine Derivatives

We have developed an efficient copper‐catalyzed method for the synthesis of the benzoxazoline‐amidine derivatives. The protocol uses inexpensive copper(I) iodide as the catalyst, and furnished the expected product in good to excellent yields by a three‐component reaction of sulfonyl azides, terminal alkynes and Schiffs’ bases in terahydrofuran (THF) at room temperature for 8 h in the presence of triethylamine. This novel synthetic protocol is selective, efficient and general. A plausible mechanism for this process is proposed.     

Zur Aminolyse von Bis-Imidoylchloriden der Oxalsäure II. Umsetzung mit Diaminen und Aminoalkoholen

On the Aminolysis of Bis-Imidoylchlorides of Oxalic Acid. II. Reaction with Aliphatic Diamines and Aminoalcohols The aminolysis of bis-imidoylchloride 1 derived from oxalic acid with several diamines and aminoalcohols was investigated. At room temperature diamines 2 as well as aminoalcohols 7 give mainly the cyclic amidines 3 and mixed amidine-imidates 8 in moderately up to good yields. While cis-1,2-diaminocyclohexane yields at room temperature the bicyclic amidine 3a , the trans isomer reacts to 3b only when heated for several hours. Depending on the conditions, the racemic 1,2-diaminopropane 2h gives derivatives of pyrazine 3h or the open-chain amidine 5 resulting from an oxidative aromatization and subsequent hydrolysis. Histamine 2i and 1,8-diamino-3,6-dioxaoctane 2p react selectively with 1 to seven- respectively twelve-membered heterocycles 3i and 3p. The mixed aliphatic and aromatic diamines 2n, o show an anomalous behaviour leading to 2,2′-bis-chinazolines 3n, o . In comparison with acyclic oxalic amidines the new cyclic derivatives show less molecular dynamic in their nmr spectra. In some cases, a s-trans-arrangement of the amidine substructure was observed.     

Chemistry and biological activity of platinum amidine complexes

Platinum amidine complexes represent a new class of potential antitumor drugs that contain the imino moiety HN=C(sp(2)) bonded to the platinum center. They can be related to the iminoether derivatives, which were recently shown to be the first Pt(II) compounds with a trans configuration endowed with anticancer activity. The chemical and biological properties of platinum amidine complexes, and more generally of platinum imino derivatives, can be rationally modified through suitable synthetic procedures with the aim of improving their cytotoxicity and antitumor activity. The addition of protic nucleophiles to nitriles coordinated to platinum in various oxidation states can offer a wide variety of complexes with chemical, structural, and physical properties specifically tuned for a more efficacious biological response.     

对氨基苯磺酸铝催化苯乙酮、芳香醛和芳香胺的“一锅法”Mannich反应

室温条件下,对氨基苯磺酸铝可有效催化苯乙酮、芳香醛和芳香胺的Mannich反应,三组分"一锅法"合成了系列β-氨基酮衍生物。考察了反应条件对收率的影响及对氨基苯磺酸铝对不同底物Mannich反应的催化效果,推测了反应机理。产物结构经IR、~1H NMR和质谱进行表征。合成不同的β-氨基酮衍生物的较佳反应条件为:苯乙酮、芳香醛和芳香胺物质的量比为1.1:1:1,对氨基苯磺酸铝用量为苯甲醛物质的量的3%,乙醇用量5 mL。该方法操作简单,条件温和,收率高,催化剂可重复使用,对环境友好。     

光学活性棉酚衍生物的合成

以色氨酸甲酯盐酸盐、醋酸棉酚、NaOH和95%的乙醇为起始原料,经中和、希夫碱反应,合成了光学活性棉酚衍生物并对其工艺进行改进。异构体分离得到光学活性棉酚衍生物,其结构和旋光性采用红外光谱（IR）、核磁（NMR）、圆二色光谱（CD）和旋光仪进行了鉴定,收率为100%,含量为98%。目标产物合成简单,反应条件温和,适合于放大生产,为棉酚衍生物的合理利用打下了良好前期工作基础。     

Electrogenerated base-promoted synthesis and antimicrobial activity of 2-imino-1,3-thiazolidin-4-one derivatives

Electrogenerated cyanomethylanions obtained by reduction of dry acetonitrile at a steel grid cathode were used to promote the addition of ethyl bromoacetate to thiourea derivatives. The reaction yields the corresponding 2-imino-1,3-thiazolidin-4-one. The reaction pathway was discussed based on the kinetic and thermodynamic data obtained by computational methods. In addition, the biological activity of these new compounds was also investigated.     

Optimization of the Cementation Process for the Removal of Copper in Process Effluent Discharges

Cementation is an effective process that meets the requirements of process cleanliness. The performance of the cementation reaction is dictated by a number of variables. In this study, the effects of various parameters on the yields of copper‐iron cementation (wire and powder) were investigated. Statistical full factorial designs were used to produce appropriate mixture models for the yields. The experimental designs were done at three different levels of three operating variables, namely initial concentration, temperature, and pH. The optimization studies were carried out with MATLAB 7.0 software. The optimum yields obtained from the predicted models were found to be 0.9916 and 0.9088 for iron wire and powder, respectively, under optimized conditions, and these were in accordance with the experimental observations.     

1,3,4-三(4-甲氧苯基)-4H-1,2,4-三唑高氯酸盐的合成

以酰氯、苯胺为起始原料依次合成酰胺、亚胺氯化物、脒后制备卡宾释放前体。产物总收率81.3%,并通过1 HNMR、IR、HRMS确认。     

色满酮类化合物的合成及其抗炎活性研究

设计合成了4种色满酮类化合物,并利用熔点、红外光谱、核磁共振氢谱等手段确定了其结构。采用二甲苯致小鼠耳肿胀法,测定了该化合物的抗炎活性,实验结果表明在200mg／kg剂量下所合成的3个目标化合物6-[2-（4-吗啉基）乙氧基]色满酮、6-[（喹啉-2-基）甲氧基]色满酮、7-[2-（4-吗啉基）乙氧基]色满酮对二甲苯所致小鼠耳肿胀具有显著的抑制作用。     

Zur Reaktion der N-Sulfinylamine mit Isocyaniden und die Synthese von 2,5-Diaryl-3,4-diarylimino-1,2,5-thiadiazolidin-S-oxiden

The Reaction of N-Sulfinylamines with Isocyanides and Synthesis of 2,5-Diaryl-3,4-diarylimino-1,2,5-thiadiazolidin-S-oxides N-Sulfinylamines 1 react with isocyanides 2 to give isocyanates 3 , isothiocyanates 6 , and especially 2,5-diaryl-3,4-diarylimino-1,2,5-thiadiazolidin-S-oxides 7 . This new heterocyclic ring system 7 can also be synthesized in high yields by a cyclization reaction of tetraarylated oxalic amidines 9 with thionyl chloride. The acid catalyzed hydrolysis of the heterocyclic compounds 7 leads to oxalic anilides 8 , the hydrolysis with alkali forms amidines 9 . The amidine 9a reacts with N-sulfinyl-p-toluenesulfonamide 11 to give an open chained adduct 12 .     

Ammonium Formate-Pd/C as a New Reducing System for 1,2,4-Oxadiazoles. Synthesis of Guanidine Derivatives and Reductive Rearrangement to Quinazolin-4-Ones with Potential Anti-Diabetic Activity

1,2,4-Oxadiazole is a heterocycle with wide reactivity and many useful applications. The reactive O-N bond is usually reduced using molecular hydrogen to obtain amidine derivatives. NH₄CO₂H-Pd/C is here demonstrated as a new system for the O-N reduction, allowing us to obtain differently substituted acylamidine, acylguanidine and diacylguanidine derivatives. The proposed system is also effective for the achievement of a reductive rearrangement of 5-(2′-aminophenyl)-1,2,4-oxadiazoles into 1-alkylquinazolin-4(1H)-ones. The alkaloid glycosine was also obtained with this method. The obtained compounds were preliminarily tested for their biological activity in terms of their cytotoxicity, induced oxidative stress, α-glucosidase and DPP4 inhibition, showing potential application as anti-diabetics.     

Möglichkeiten zum Nachweis semicyclischer Amidinendgruppen in Polycaprolactam durch Abspaltung des Amidinheterocyclus. Untersuchungen an niedermolekularen Modellamidinen und an peramidiniertem Polycaprolactam

In search of new identification methods for terminal semicyclic amidine groups in polyamide 6, a study was made with model compounds to investigate whether the amidine heterocycle could be transformed with CH-acid methylene compounds and primary nitrogen bases in an identifiable form. It was found, that high concentrated hydrazine hydrat changes semicyclic amildines, the type of which is formed in polyamide 6, quantitatively into 2-hydrazino-l-aza-eyelohepten-(I). By the hydrazinolysis of polyamide 6, all amino groups of which were converted into amidine groups, after deamination a rapid decrease of the residual basicity was noted, which could be related to the separation of the amidine heterocycle by intermediate formation of 2-hydrazino-l-aza-cyclohepten-(1). However, this product due to its very small concentration and insufficient stability could not be identified. With CH-acid methylene compounds and ammonia the reaction is only possible when the exocyclic amidine nitrogen is dialkylated. Concluding, from the results obtained, the hydrazinolysis could be the best way for a direct identification and a quantitative determination of terminal semicyclic amidine groups in poly-amide 6.     

A numerical study on biomass fast pyrolysis process: A comparison between full lumped modeling and hybrid modeling combined with CFD

This study focuses on process modeling and simulation of a biomass fast pyrolysis system. For the simulation of the biomass fast pyrolysis process, two types of simulation models were developed: lumped model and hybrid model. Employing the above models, the effect of reaction temperature on reaction rate and final product yields were analyzed. It was found that the hybrid model exhibited a peculiar characteristic of displaying multiphase reacting flow occurring in fluidized bed. This behavior of hybrid model could have attributed for the difference in product yields of the models (hybrid and lumped). For the yields of the tar and NCG, hybrid model prediction was very consistent with the experimental results than the lumped model. However, for char yield, the results of both the lumped model and the hybrid model were close to that of experimental results.     

Versatile 2-amino-4-substituted-1,3-thiazoles: synthesis and reactions

Syntheses and reactions of 2-amino-4-substituted-1,3-thiazoles are reviewed in a formal way. The title compounds are most easily accessible by various approaches, and even waste-free solid-state procedures have been developed. The substitution in 4-position has synthetic reasons and therefore most interest accumulates around these derivatives of 2-aminothiazole. The high reactivity of both the amino group and the positions 3 and 5 of the 1,3-thiazole ring are used for numerous syntheses in a comprehensive way. The reactions are subdivided in groups that cover reactions at the amino substituent without touching the thiazole ring, reactions which involve both nitrogens in the formal amidine system to give thiazolo-pyrimidinones and -imidazoles as well as more involved polycondensed N,S-heterocycles with multiple possibilities for substituents, and substitution reactions at the 5-position of the thiazole ring. Most of the imaginable reaction types have been successfully applied and used, as many of the synthesized compounds exhibit interesting biological activity in various fields.     

Keggin型硅钨酸高效催化一锅法合成β-氨基酮衍生物

温和条件下,以硅钨酸为催化剂,酮、芳香醛和芳香胺为原料,三组分"一锅法"合成了15个β-氨基酮衍生物,并考察了反应条件对产率的影响。该反应条件温和,操作简单且产物易分离,产率较高。     

A Mild,Highly Efficient Addition of Alkynes to Aldehydes Catalyzed by Titanium Dioxide‐Supported Silver Nanoparticles

Titanium dioxide‐supported silver nanoparticles were utilized as a highly efficient catalyst for the addition of terminal alkynes to aldehydes to prepare propargylic alcohols with the promotion by triphenylphosphine. Both a significant support effect and a ligand effect were observed in the catalytic reaction. With this protocol, various propargylic alcohol derivatives were synthesized from aldehydes and terminal alkynes in good to excellent yields. Furthermore, the catalyst could be recovered and reused effectively without obvious reduction in catalytic activity.     

[60]富勒烯三元环化反应及其衍生物功能研究

对[60]富勒烯的三元环化反应及其衍生物的功能研究进行了概述,讨论了[60]富勒烯的三元环化反应的发生机理.重点阐述了[60]富勒烯三元环化典型反应及获得的富勒烯衍生物的生物医药功能等,对今后的工作进行了展望.     

Application of MIA for a QSAR Study of Inhibitory Activity of DHP Derivatives and Design of New Compounds Using WT and GA for Pixel Processing

A quantitative structure-activity relationship (QSAR) modeling was carried out for the prediction of inhibitory activity of dihydropyridine (DHP) derivatives known as calcium channel blocker (CCB) drugs. Partial least squares (PLS) algorithm was used for prediction of inhibitory activity of calcium channel antagonists as a function of the bidimensional images. In the present study, it is investigated that the effect of pixel selection by application of genetic algorithms (GAs) for PLS model, because of the GAs is very useful in the variable selection in modeling. Pre-processing methods such as wavelet transform (WT) were also used to enhance the predictive power of multivariate calibration methods. The subset of pixels, which resulted in the low prediction error, was selected by GA. To evaluate the models applied in this study (PLS, GA-PLS and WT-GA-PLS), the inhibitory activities of several compounds, not included in the modeling procedure, were predicted. The results of models showed high prediction ability with root mean square error of prediction (RMSEP) of 0.51, 0.39 and 0.17 for PLS, GA-PLS and WT-GA-PLS, respectively. The WT-GA-PLS method was employed to predict the inhibitory activity of the new antagonists.     

The anti-inflammatory activity of boron derivatives in rodents

Acyclic amine-carboxyboranes were effective anti-inflammatory agents in mice at 8 mg/kg x 2. These amine-carboxyboranes were more effective than the standard indomethacin at 8 mg/kg x 2, pentoxifylline at 50 mg/kg x 2, and phenylbutazone at 50 mg/kg x 2. The heterocyclic amine derivatives as well as amine-carbamoylboranes, carboalkoxyboranes, and cyanoboranes were generally less active. However, selected aminomethyl-phosphonate-N-cyanoboranes demonstrated greater than 60% reduction of induced inflammation. The boron compounds were also active in the rat induced edema, chronic arthritis, and pleurisy screens, demonstrating activity similar to the standard indomethacin. The compounds were effecive in reducing local pain and decreased the tail flick reflex to pain. The derivatives which demonstrated good anti-inflammatory activity were effective inhibitors of hydrolytic lysosomal, and proteolytic enzyme activities with IC(50) 50 values equal to (-6)M in mouse macrophages, human leukocytes, and Be Sal osteofibrolytic cells. In these same cell lines, the agents blocked prostaglandin cyclooxygenase activity with IC(50) values of (-6)M. In mouse macrophage and human leukocytes, 5' lipoxygenase activity was also inhibited by the boron derivatives with IC(50) values of 10(-6)M. These IC(50) values for inhibition of these enzyme activities are consistent with published values of known anti-inflammatory agents which target these enzymes.