高纯度(>98%)三芳基-2-硼酸的合成

以卤代芳烃为原料,经硼酸化反应和Suzuki偶联反应合成了一系列三芳基-2-硼酸化合物,收率67.4%~70.1%,纯度均98%,其结构经1H NMR和元素分析确证。     

4-(2-乙氧羰基乙基)苯基硼酸的合成及工艺优化

以对甲酰基苯硼酸为起始原料,经Wittig-Horne反应、催化氢化2步反应合成了目标化合物,终产物结构经1H-NMR确证。通过单因素实验,分析了每一步反应的关键影响因素,对合成条件进行了优化,反应总收率为77.33%。该方法合成条件简单、原料廉价易得、操作简便且收率较高。     

羟苯基丙酰胺苯甲酸的合成

以苯酚为起始原料,经碳烷基化反应、水解反应、酰氯反应、酰胺反应和水解酸化等5步反应合成了羟苯基丙酰胺苯甲酸,纯度大于99.0%,其结构经¹H NMR和IR确证。     

合成萘普西诺的工艺改进

以(S)-萘普生为原料,经酯化、硝酸酯化反应合成了萘普西诺,总收率39.9%,纯度99.1%,其结构经1H NMR,IR和MS确证。     

2-甲氧基-4-氯苯甲酸的合成新方法

以间氯苯酚为原料,经乙酰化、Fries重排、O-甲基化和氧化反应合成了2-甲氧基-4-氯苯甲酸,总收率54.1%,纯度98.2%.     

降血脂药环丙贝特的合成

报道了一种合成降血脂药物环丙贝特的新工艺。以对羟基苯甲醛为原料,经Witting反应、醚化、环化及水解共4步反应合成了环丙贝特,总收率69.4%,纯度99.7%,其结构经¹H NMR, ¹³C NMR和HR-MS(ESI)确证。     

三(4-乙酰氨基苯基)甲烷的合成

以三苯甲烷为原料,经硝化、还原和乙酰化反应合成了一种新型三芳基甲烷——三(4-乙酰氨基苯基)甲烷,纯度99.74,总收率50.6%,其结构经1H NMR,FT-IR和元素分析表征。     

(S)-异丝氨酸的合成研究

以L -天冬氨酸为原料 ,经酯化、重氮化 -水解、氨解、Hofmann降解等反应合成了具有良好光学纯度的 (S) -异丝氨酸。总收率不低于35 %     

4-(N-乙基-3-甲基苯胺基）丁酸甲酯的合成

以γ-丁内酯为起始原料,经开环氯化和醇解反应合成4-氯丁酸甲酯（2）; 2与N-乙基间甲苯胺经亲核取代反应合成了4-(N-乙基-3-甲基苯胺基）丁酸甲酯,纯度97.5%,总收率75.3%,其结构经¹H NMR确证。     

左乙拉西坦杂质的合成

分别以D-氨基丁酸和DL-氨基丁酸为起始原料,经4步反应合成了右乙拉西坦和左乙拉西坦杂质A——(S)-N-(1-氨基-1-氧代丁基)-4-氯丁酰胺(纯度97.0%);左乙拉西坦经水解反应合成了左乙拉西坦酸(纯度99.9%),其结构经1H NMR和MS确证。     

Effect of aniline derivatives on the extraction of cobalt with 1-phenyl-3-methyl-4-benzoylpyrazol-5-one in toluene

Summary The effect of aniline derivatives [4-methylaniline=4-toluidine, 3,4-dimethylaniline=3,4-xylidine, N,N-dimethylaniline and tribenzylamine (Am)] on the extraction of cobalt from sulphate, nitrate and perchlorate aqueous media of 1.0M ionic strength with 1-phenyl-3-methyl-4-benzoylpyrazol-5-one (HL) in toluene, has been quantitatively studied. With both primary amines a synergic effect was found owing to theAmH·CoL ₃ ion pair extraction. TheAmH·CoL ₃ average formation constant, from CoL ₂ andAmH·CoL, was logK _s =3.7 and 3.8 forAm=4-toluidine and 3,4-xylidine respectively. With N,N-dimethylaniline and tribenzylamine which are poorly protonated in the cobalt extractionpH range (4–6), no noticeable synergism was observed.On leave from: Department of Inorganic Chemistry, Chemical Faculty, Ignacy Lukasiewicz Technical University, PL-35-959 Rzeszow, Poland     

Protolytic Equilibria of Some N,N-Bis(2-carboxyethyl)aminoazobenzenesulfonic Acids in Aqueous Solution

4-[4-Bis(2-carboxyethyl)aminophenylazo]benzenesulfonic acid and 4-[2-bis(2-carboxyethyl)amino-4,5-dimethylphenylazo]benzenesulfonic acid were synthesized for the first time by azo coupling of diazosulfanilic acid with N,N-bis(2-carboxyethyl)aniline and N,N-bis(2-carboxyethyl)-3,4-xylidine, respectively. The acid ionization constants of the products were determined, their electron absorption spectra were measured, and schemes of acid-base equilibria in aqueous solution were proposed.     

In vivo metabolism of lidocaine in the rat. Isolation of urinary metabolites as pentafluorobenzoyl derivatives and their identification by combined gas chromatography-mass spectrometry

The metabolism of a large dose (40 mg/kg intraperitoneally) of lidocaine (LIDO) in mature male Sprague-Dawley rats is described. Pentafluorobenzoyl chloride was used to derivatize the hydrolyzed urinary metabolites prior to extraction and analysis as pentafluorobenzoyl-derivatives by combined gas chromatography-mass spectrometry. Total ion and selected ion current (m/z 195; C6F5CO+) traces were recorded and metabolites of LIDO were readily identified. Only one major metabolite, 3-hydroxy-N-(N-ethylglycyl)-2,6-xylidine, was excreted in urine. A new metabolite, 3-hydroxy-N-glycyl-2,6-xylidine was also present in significant amounts, as well as minor quantities of four oxygenated metabolites of N-(N-ethylglycyl)-2,6-xylidine. Other known metabolites of LIDO, including 3-hydroxylidocaine, were excreted in trace quantities. The results suggest that metabolism of LIDO in rats may be age- and/or dose-dependent.     

The conversion of 3,4-cis- to 3,4-trans-cannabinoids

An investigation of the conversion of Δ¹-3,4-cis-THC 1a to Δ⁶-3,4-trans-THC 2a with BBr₃ is described. By use of 1a of known optical purity it was determined that the main epimerization occurs at C-4. The small loss of optical purity observed during formation of 2a results from either competitive epimerization at C-3 or a racemization process. The conversion of 3,4-cis- to 3,4-trans-HHCs proceeds with exclusive C-4 inversion.     

High-throughput parallel synthesis of 3,4-disubstituted 1-(ω-hydroxyalkyl) imidazolin-2-ones on ‘volatilizable’ supports

A solid-phase synthesis of 3,4-disubstituted 1-(ω-hydroxyalkyl) imidazolin-2-ones on the ‘volatilizable’ aminoalkyl functionalized silica gel is reported. The desired products were cleaved by a two-step procedure in good purity and yield.     

One-step purification of 3,4-dihydroxyphenyllactic acid, salvianolic acid B, and protocatechualdehyde from Salvia miltiorrhiza Bunge by isocratic stepwise hydrogen bond adsorption chromatography on cross-linked 12% agarose

Three major active components of the traditional Chinese medicinal herb Salvia miltiorrhiza Bunge, 3,4-dihydroxyphenyllactic acid, salvianolic acid B, and protocatechualdehyde, are separated and purified from a crude water extract in one step by isocratic hydrogen bond adsorption chromatography on cross-linked 12% agarose (Superose 12 HR 10/30). Separation is achieved by stepwise elution with mobile phases composed of mixtures of ethanol and acetic acid: 0-50 mL, 5% ethanol, 5% acetic acid; 50-100 mL, 20% ethanol, 20% acetic acid; and 100-200 mL, 30% ethanol, 30% acetic acid. The 3,4-dihydroxyphenyllactic acid is obtained with a purity of 97.3% and with a recovery of 88.1%. The corresponding figures for protocatechualdehyde are a purity of 99.4% with a recovery of 90.7%, and for salvianolic acid B a purity of 90.4% with a recovery of 50.3%, respectively. At a sample load of 40 mg crude extract dissolved in 0.5 mL mobile phase (corresponding to a load of 1.6 mg/mL gel), a 3,4-dihydroxyphenyllactic acid purity of approximately 94% with a recovery of 80.2% is obtained.     

Aromatic amino-claisen rearrangement in the synthesis of ellipticine

A convenient route is described for the preparation of 1,4-dimethylcarbazole — the key compound in the synthesis of the antitumoral alkaloid ellipticine. The interaction of 2,5-xylidine with 3-chlorocyclohexene led to N-(cyclohex-2-enyl)-2,5-xylidine (I), the two-hour heating of which at 140–150°C gave the product of an amino-Claisen rearrangement, 6-(cyclohex-2-enyl)-2,5-xylidine (II) with a yield of 82%. The intramolecular cyclization of compound (II) in polyphosphoric acid (130–140°C, 5 h) led to 5,6,7,8,12,13-hexahydro-1,4-dimethylcarbazole (III) in a yield of 75%. The dehydrogenation of substance (III) by boiling in trimethylbenzene in the presence of Pd/C gave 1,4-dimethylcarbazole (IV) with a yield of 87%. The conditions for performing the reactions and the physicochemical constants of the compounds obtained are given.     

Crystal structure of the Hofmann-dma type clathrate

Seven new Hofmann-dma type clathrates Cd(dma)₂Ni(CN)₄-xG (x = 1, G = aniline, 2,3-xylidine, 2,4-xylidine, 2,5-xylidine, 2,6-xylidine, 3,5-xylidine and x = 2, G = 2,4,6-trim ethylaniline) were prepared by replacing the amine in a Hofmann type clathrate Cd(NH₃)₂Ni(CN)₄-2G by dimethylamine (dma). The structure of the Hofmann-dma type clathrate is formed with stacked host two-dimensional metal complexes of Cd(dma)₂ Ni(CN)₄ and guest molecules accommodated in the space between the stacked host complexes. This basic structure scheme is the same as that of the Hofmann type clathrate. However, the guest species accommodated in the Hofmann-dma type clathrate are more various than those of the Hofmann type clathrate, and their crystal structures are classified into four types depending on the geometry of the guest species. In order to clarify the structure of the Hofmann-dma type clathrate, single crystal X-ray diffraction experiments were canied out on the seven new clathrates, and the crystal structures of the o-, m- and p- toluidine clathrates were refined. The X-ray structure analyses showed that the host two-dimensional metal complex of the Hofmann-dma tvpe clathrate has stmctural flexibility to form a puckered structure, which results from the angular distortion of the bond between Cd and N of the cyanide bridge in the host two-dimensional complex. This stmctural flexibility of the host complex leads to the diversity of crystal structures and guest species in Hofmann-dma type clathrates. Translated fromZhurnal Strukturnmoi Khimii, Vol. 40, No. 5, pp. 898–926, September–October, 1999.     

Production of core/shell polystyrene/poly(3,5-xylidine) composite particles by chemical oxidative seeded dispersion polymerization

Micron-sized monodispersed polystyrene (PS)/poly(3,5-xylidine) (PXy) composite particles were produced by chemical oxidative seeded dispersion polymerization of 3,5-xylidine at 20 °C with 1.6-μm-sized monodispersed PS seed particles in HCl aqueous solution, the pH of which was always kept at 2.5 with a pH stat. The composite particles produced consisted of a PS core and a PXy shell. Received: 16 December 1998 Accepted in revised form: 25 March 1999     

化学-酶催化制备天然丹参素

丹参素是中药丹参的水溶性化学成分之一,具有很多潜在的药理活性。 以3,4-二羟基苯甲醛和乙酰甘氨酸为原料,经Erlenmeyer反应并开环得到α-乙酰氨基-β-(3,4-二乙酰氧基苯基)丙烯酸、盐酸水解制得β-(3,4-二羟基苯基)丙酮酸,再经乳酸片球菌1.2696静息细胞生物酶催化还原合成了天然右旋丹参素,总收率69.4%,丹参素对映体过量值97.5%。