Xu X.,Zhejiang University |
Sun C.-R.,Zhejiang University |
Dai X.-J.,Zhejiang University |
Hu R.-L.,Zhejiang University |
And 2 more authors.
Molecules | Year: 2011
The traditional methods used in natural product separation primarily target the major components and the minor components may thus be lost during the separation procedure. Consequently, it's necessary to develop efficient methods for the preparative separation and purification of relatively minor bioactive components. In this paper, a LC/MS method was applied to guide the separation of crude extract of lotus (Nelumbo nucifera Gaertn.) leaves whereby a minor component was identified in the LC/MS analysis. Afterwards, an optimized pH-zone-refining CCC method was performed to isolate this product, identified as N-demethylarmepavine. The separation procedure was carried out with a biphasic solvent system composed of hexane-ethyl acetate-methyl alcohol-water (1:6:1:6, v/v) with triethylamine (10 mM) added to the upper organic phase as a retainer and hydrochloric acid (5 mM) to the aqueous mobile phase eluent. Two structurally similar compounds - nuciferine and roemerine - were also obtained from the crude lotus leaves extract. In total 500 mg of crude extract furnished 7.4 mg of Ndemethylarmepavine, 45.3 mg of nuciferine and 26.6 mg of roemerine with purities of 90%, 92% and 96%, respectively. Their structures were further identified by HPLC/ESIMSn, FTICR/MS and the comparison with reference compounds. © 2011.
Ying A.,Taizhou University |
Zheng M.,Zhejiang Hisoar Pharmaceutical Co. |
Xu H.,Taizhou University |
Qiu F.,Taizhou University |
Ge C.,Taizhou University
Research on Chemical Intermediates | Year: 2011
An efficient and facile protocol for aza-Michael addition of aliphatic and aromatic amines to electron-deficit alkenes using [TMG][Lac] as catalyst under solvent-free conditions was established. © 2011 Springer Science+Business Media B.V.
Zhejiang Hisoar Pharmaceutical Co. | Date: 2013-05-29
Medicines for human purposes; pharmaceutical preparations; chemico-pharmaceutical preparations; analgesics; evacuants; febrifuges; sedatives; antibiotics; pharmaceutical preparations for injection; pharmaceutical preparations in tablet form.
Zhejiang Hisoar Pharmaceutical Co. | Date: 2011-12-01
Disclosed are intermediates of Sitagliptin, a preparation process thereof, and a process for synthesizing Sitagliptin using these intermediates. Sitagliptin is synthesized by using chiral amino compounds as a raw material, without having to build a chiral center with a chiral asymmetric catalytic hydrogenation, and high-pressure hydrogenation is avoided.
Zhejiang Hisoar Pharmaceutical Co. | Date: 2010-02-08
Disclosed is a method for preparing 7-halo-2-oxoheptylate, an intermediate of cilastatin. The main steps are as follows: A. Addition reaction, in which 6-halo-hexanal is reacted with a cyanide to obtain 7-halo--hydroxyl-heptonitrile; B. Hydrolysis reaction, in which 7-halo--hydroxyl-heptonitrile is converted to 7-halo--hydroxyl-heptylic acid; C. Esterification reaction, in which 7-halo--hydroxyl-heptylic acid is converted to 7-halo--hydroxyl-heptylate; and D. Oxidation reaction, in which 7-halo--hydroxyl-heptylate is converted to 7-halo-2-oxoheptylate. 7-halo--hydroxyl-heptylic acid or ester thereof, which is a new intermediate for synthesizing 7-halo-2-oxoheptylate or cilastatin, and a method for synthesizing cilastatin are also disclosed. The methods of the invention are suitable for commercial production because of their simple process and mild reaction condition.