共查询到18条相似文献,搜索用时 78 毫秒
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氨噻肟酸是一种重要的医药中间体,主要用于合成头孢菌素抗生素制剂。这种抗生素制剂是国外20世纪70年代发展起来的抗菌力很强的新型抗菌素药物,目前该类抗生素的世界销售额约占整个抗生素药物市场销售总额的35%。氨噻肟酸是用于合成第三代头孢菌素即先锋霉素的原料,这一类称为氨噻肟头孢 相似文献
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氨噻肟酸乙酯测定方法的研究赵惠莲赵有贵(河北化工学校石家庄市050031)1前言氨噻肟酸乙酯是合成头孢菌素药物的重要中间体。近年来,随着制药业的发展,越来越受到医药界的重视,但此物质的定量分析还未见报道。为了更好地指导生产,控制产品质量,研究确定一种... 相似文献
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Z-2-(2-氨基噻唑-4-基)-2-甲氧亚氨基乙酰氯盐酸盐的制备 总被引:1,自引:0,他引:1
以2-(2-氨基噻唑-4-基)-2-甲氧亚氨基乙酸为原料,经盐酸化、氯代等反应合成了Z-2-(2-氨基噻唑-4-基)-2-甲氧亚氨基乙酰氯盐酸盐;氯代时以用亚硫酰氯和N, N-二甲基甲酰胺的混合物代替五氯化磷作氯化剂,并考察了温度和溶剂对氯代产物中Z-异构体和E-异构体收率的影响.结果表明:在(15℃下,用亚硫酰氯和N, N-二甲基甲酰胺的混合物作为氯化剂,用二氯甲烷作溶剂合成的标题化合物为白色的对温度稳定的晶体,总收率可达70%以上,而且基本不含黄色的对温度不稳定的E-异构体.用其作为氨基酰基化试剂进一步合成盐酸头孢吡肟,也得到基本上白色的对温度稳定的不含E-异构体的晶态化合物.标题化合物和盐酸头孢吡肟的结构通过核磁共振氢谱确定.本工艺操作简便,反应条件温和,适合工业化生产. 相似文献
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2-(2-氨基噻唑-4-基)-2-(Z)-甲氧亚胺基乙酸苯并噻唑硫酯合成工艺的改进 总被引:4,自引:1,他引:4
对2-(2-氨基噻唑-4-基)-2-(Z)-甲氧亚胺基乙酸苯并噻唑硫酯(Ⅶ)的合成工艺进行了改进研究,即以价格相对便宜的乙酰乙酸甲酯代替目前工业上普遍采用的乙酰乙酸乙酯为原料,通过亚硝化、醚化、溴化、环合、水解、脱水、硫酯化7步反应制备Ⅶ,总收率31.6%(摩尔)。水解反应采用氢氧化钠-甲醇-水体系代替氢氧化钠-水体系;环合反应采用N,N-二甲基苯胺代替乙酸钠;溶剂用二氯甲烷代替乙醇-水,使环合物颜色较浅;硫酯化反应做了重大改进,采用廉价的亚磷酸三乙酯(2万元/t)代替昂贵易水解的三苯基磷(12万元/t)。基于工艺改进,Ⅶ的成本由20万元/t降到13万元/t。所得活性酯试用于头孢噻肟钠、头孢地嗪钠的合成,产品合格。 相似文献
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GAO Shihao SUN Chenghui ZHAO Xinqi GAO Changquan 《Frontiers of Chemical Science and Engineering》2008,2(1):80
2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl thioester(III), an important intermediate of the fourth generation cephalosporins, was efficiently synthesized by reacting 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid (I) with 2,2′-dibenzothiazole disulfide (II) in the presence of triphenylphosphine. Effects of reaction time, temperature, solvents, catalysts and feeding molar ratio on the yield and quality of products were investigated, and an improved procedure suitable for industrial production was established. Using 1,2-dichloroethane as solvent, triphenylphosphine as reducer, and triethylamine as catalyst, n(I) : n(II) : n(triphenylphosphine) = 1.0 : 1.0 : 1.0, the product was obtained at room temperature in 98.1% yield. The purity of the product without further purification is 98.7% determined by HPLC method. This procedure could be a suitable alternative to the traditional processes because of its easy handling, high yield and low cost. 相似文献
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Shihao Gao Changquan Gao Chenghui Sun Xinqi Zhao 《Frontiers of Chemical Engineering in China》2008,2(1):80-84
2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl thioester(III), an important intermediate
of the fourth generation cephalosporins, was efficiently synthesized by reacting 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic
acid (I) with 2,2′-dibenzothiazole disulfide (II) in the presence of triphenylphosphine. Effects of reaction time, temperature,
solvents, catalysts and feeding molar ratio on the yield and quality of products were investigated, and an improved procedure
suitable for industrial production was established. Using 1,2-dichloroethane as solvent, triphenylphosphine as reducer, and
triethylamine as catalyst, n(I): n(II): n(triphenylphosphine)51.0: 1.0: 1.0, the product was obtained at room temperature in 98.1% yield. The purity of the product
without further purification is 98.7% determined by HPLC method. This procedure could be a suitable alternative to the traditional
processes because of its easy handling, high yield and low cost.
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Translated from Fine Chemicals, 2007, 24(8): 816–819 [译自:精细化工] 相似文献