tert-Butyl （R）-3-amino-3-（3-fluorophenyl）propanoate（5） was prepared with conventional debenzylation method. However, the tert-butyl （R）-3-[（S）-1-phenylethyl-amino]-3-（3-fluorophenyl） propanoate（6） and te...tert-Butyl （R）-3-amino-3-（3-fluorophenyl）propanoate（5） was prepared with conventional debenzylation method. However, the tert-butyl （R）-3-[（S）-1-phenylethyl-amino]-3-（3-fluorophenyl） propanoate（6） and tert-butyl （R）-3-amino-3-phenylpropanoate（7） were generated as the byproducts under the general catalytic hydrogenation Pd（OH）2/C-H2 conditions. So a series of experiments was performed to optimize the reaction conditions so that product 5 could be obtained with high purity and yield. Finally an effective catalytic system, Pd/C-HCOOH-CH3OH, was discovered.展开更多
Dexmedetomidine and its novel salt have been synthesized and characterized by single-crystal XRD and TGA/DSG. Components of the crystalline phase have also been investigated in terms of their corresponding Hirshfeld s...Dexmedetomidine and its novel salt have been synthesized and characterized by single-crystal XRD and TGA/DSG. Components of the crystalline phase have also been investigated in terms of their corresponding Hirshfeld surface. In the crystal lattice, a three-dimensional hydrogen-bonded network is observed. In this work, the salt strategy has been applied successfully to dexmedetomidine. One important parameter, i.e. stability, has also been significantly improved, which proves to be an important factor for solid dosage formulation. Furthermore, DSC/TGA analysis indicates that the salt maintains its crystallinity up to 300℃, suggesting a higher stability of the salt compared to pure dexmedetomidine.展开更多
基金Supported by the National Key New Drug Creation Program of China(No.2009ZX09103-001)the Jiangsu Key Laboratory of Molecular Targeted Antitumor Drug Research Foundation China(No.BM2008201)
文摘tert-Butyl （R）-3-amino-3-（3-fluorophenyl）propanoate（5） was prepared with conventional debenzylation method. However, the tert-butyl （R）-3-[（S）-1-phenylethyl-amino]-3-（3-fluorophenyl） propanoate（6） and tert-butyl （R）-3-amino-3-phenylpropanoate（7） were generated as the byproducts under the general catalytic hydrogenation Pd（OH）2/C-H2 conditions. So a series of experiments was performed to optimize the reaction conditions so that product 5 could be obtained with high purity and yield. Finally an effective catalytic system, Pd/C-HCOOH-CH3OH, was discovered.
基金supported by the prospective joint research project of Jiangsu province(BY20122193)the Fundamental Research Funds for the Central Universities(CXZZ12_0119)
文摘Dexmedetomidine and its novel salt have been synthesized and characterized by single-crystal XRD and TGA/DSG. Components of the crystalline phase have also been investigated in terms of their corresponding Hirshfeld surface. In the crystal lattice, a three-dimensional hydrogen-bonded network is observed. In this work, the salt strategy has been applied successfully to dexmedetomidine. One important parameter, i.e. stability, has also been significantly improved, which proves to be an important factor for solid dosage formulation. Furthermore, DSC/TGA analysis indicates that the salt maintains its crystallinity up to 300℃, suggesting a higher stability of the salt compared to pure dexmedetomidine.
