Reactions of benzoylheteroaroylmethanes with hydroxylamine hydrochloride

Benzoyl-2-furoylmethane reacts with hydroxylamine hydrochloride to give predominantly 5-(2-furyl)-3-phenylisoxazole and not as reported in the literature 3-(2-furyl)-5-phenylisoxazole. Benzoyl-2-thenoylmethane and benzoylpicolinoylmethane afforded 3-phenyl-5-(2-thienyl)isoxazole and 5-phenyl-3-(2-pyridyl)isoxazole respectively.     

Hydration of tri-n-hexyl amine hydrochloride,tri-n-octyl amine hydrochloride,tri-n-decyl amine hydrochloride and tri-n-dodecyl amine hydrochloride benzene solutions

Isopiestic equilibrations of THxA·HCl, TOA·HCl, TDA·HCl and TLA·HCl benzene solutions have been made in the concentration range from 0·02 to 0·13 mole/kg at different water activities and 25°C. The mean hydration number of the chloride ion at unit water activity was found to be 1·024±0·015 for the systems investigated. To determine the effect of water activity on the amine salt activity the results were treated on the basis of the Gibbs-Duhem equation and a simple linear relation obtained between salt and water activities. IR spectrophotometric measurements were performed to identify the nature of the hydrated species.     

Thermochemistry on ephedrine hydrochloride and N-methylephedrine hydrochloride

The crystal structures of ephedrine hydrochloride and N-methylephedrine hydrochloride have been determined by X-ray crystallography. The molar enthalpies of dissolution of the two compounds with various molalities were measured at T = 298.15 K in distilled water by means of isoperibol solution-reaction calorimeter, respectively. According to the theory of Pitzer, the molar enthalpies of dissolution of the two compounds at infinite dilution, ${\mathrm{\Delta }}_{\text{s}}{H}_{\text{m}}^{\infty }$, and Pitzer’s parameters ${\beta }_{\text{MX}}^{(0)L}\text{,}{\beta }_{\text{MX}}^{(1)L}\text{,}\text{and}{C}_{\text{MX}}^{{}^{\Phi }L}$, were obtained. Then the values of apparent relative molar enthalpies $({}^{\Phi }L)$, hydration heat, and relative partial molar enthalpies of the two compounds $({\overline{L}}_2)$ were derived from the experimental results of the enthalpies of dissolution of the two compounds. Finally, the ionic radius of the cations can be calculated from the data of the corresponding effective volume of the cations.     

Spectrophotometric determination of nicoumalone, acebutolol hydrochloride and procainamide hydrochloride

A sensitive spectrophotometric method is described for the determination of nicoumalone (NIC), acebutolol hydrochloride (ACBH) or procainamide hydrochloride (PAH) either in pure form or in pharmaceutical formulations. The method is based on the oxidative coupling reaction through the involvement of an aromatic primary amino group (released through reduction in NIC or hydrolysis in ACBH or existing free in PAH) in the drug with 3-methyl-2-benzothiazolinone hydrazone hydrochloride (MBTH) in the presence of ferric chloride [Fe(III)]. The resulting chromophores are measured at 620 nm for NIC and ACBH and 580 nm for PAH. The concentration measurements are reproducible within a relative standard deviation of 1%.     

流动注射-化学发光方法测定盐酸萘甲唑林和盐酸氧甲唑林

H2SO4酸性条件下,甲醛对KMnO4-盐酸萘甲唑林(盐酸氧甲唑林)化学发光体系有较强的增敏作用,且强度与药物浓度呈良好的线性关系.据此,建立了采用KMnO4-甲醛体系测定制剂中盐酸萘甲唑林(盐酸氧甲唑林)的流动注射-化学发光分析法.在优化的实验条件下,盐酸萘甲唑林在1.0×10-8～7.0×10-6g/mL范围内呈良好的线性关系,检出限为8.69×10-9g/mL;盐酸氧甲唑林在5.0×10-8～1.0×10-5范围内呈线性关系,检出限为3.47×10-8g/mL.对浓度为1.0×10-6g/mL的盐酸萘甲唑林和盐酸氧甲唑林分别进行的11次平行测定,RSD分别为4.0%和4.1%.     

盐酸替罗非班的合成

以L-酪氨酸为原料,经过酯化、磺酰化、mitsunobu反应、水解、催化氢化等几步反应制得盐酸替罗非班,目标产物的化学结构经1H-NMR、IR、MS等确证,总收率为33%。     

盐酸金刚乙胺的合成

盐酸金刚乙胺(1)是一种抗病毒和镇静药物,主要用于预防和治疗Ａ型流感病毒感染[1]。文献[2,3]以溴代金刚烷(3)为原料,在浓硫酸存在下与乙炔气体反应,然后水解得到中间体1 金刚烷甲基酮(7),且产物需经过柱分离,总收率40%。本文参考文献[4,5],按如下路线合成了标题化合物。1　实验部分1.1　主要仪器和试剂ＩＲ(60ＳＸＲ ＦＴＩＲ);1Ｈ ＮＭＲ(ＦＸ 90Ｑ);ＭＳ(ＭＡＴ 2000)。熔点用毛细管法测定,温度计未经校正。金刚烷(工业品)98%;浓硫酸(工业品)98 4%;其它试剂为化学纯。1.2　合成1 溴代金刚烷(3)　在烧瓶中,依次加入2(320ｇ,2.35ｍｏｌ…     

Structure of dimethylaminodihydroarglabin hydrochloride

The structure of dimethylaminodihydroarglabin hydrochloride has been determined on the basis of the results of an x-ray structural investigation.Institute of Phytochemistry, Ministry of Science and Higher Education, Republic of Kazakhstan, 470032, Karaganda, Ul. Erzhanova, a/ya 19, fax 433773 E-mail: arglabin@phyto.karaganda.su. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 339–341, May–June, 1999.