L-酪氨酸甲乙丁酯盐酸盐的合成研究

合成L-酪氨酸甲酯盐酸盐、L-酪氨酸乙酯盐酸盐、L-酪氨酸丁酯盐酸盐。以L-酪氨酸为原料,采用氯化亚砜法和氯化氢法,分别与甲醇、乙醇、丁醇反应,得到L-酪氨酸甲酯盐酸盐、L-酪氨酸乙酯盐酸盐、L-酪氨酸丁酯盐酸盐,其结构经MS确证。两种方法均具有原料价廉易得,反应周期短,催化剂易得,产物易分离的特点,适于工业化大规模生产。

盐酸多巴甲酯对映体的HPCE手性拆分

Aim:To develop an HPCE method for the chiral separation of dopa methyl ester hydrochloride enantiomers.Methods:The enantiomers were separated by HPCE on a capillary of 63.5/72.0(I/L)cm×50 μm(i.d) with the background electrolyte of 20 mmol/L sodium dihydrogen phosphate,which containing 2.5% of highly sulfated-β-cyclodextrin as the chiral resolving additive adjusted to pH 2.55 with phosphoric acid.The outlet pressure injection mode and positive voltage of 30 kV electric force were used with the cassette temperature at 25 ℃ and UV detection at 210 nm.Attempts were made to optimized the separation conditions.Results:The enantiomers were baseline separated at the optimized conditions with the resolution greater than 2.The calibration curve was linear for L-dopa methyl ester hydrochloride in the range from 10 to 4 000 μg/mL using aminobenzoic acid as internal standard.And the limit of detection was 2.0 μg/mL.Conclusion:The established HPCE method is of high performance and economy for the chiral separation.It could be used as the routine method for the chiral purity analysis of L-dopa methyl ester hydrochloride.

一种那格列奈的合成方法

D-苯丙氨酸甲酯化生成D-苯丙氨酸甲酯盐酸盐,将反式-4-异丙基环己甲酸与氯甲酸乙酯酰氯化后,加入D-苯丙氨酸甲酯盐酸盐,得到那格列奈甲酯,用氢氧化钠溶液水解后,调酸析晶,得那格列奈,再在丙酮与纯化水作用下转晶型成H型那格列奈。该工艺具有操作简单、高效、收率较高、低毒、对环境友好等优点,总收率74%。