Objective To develop the analytical method to determine the content of dexamethasone in human plasma by solid phase extraction with ultra performance liquid chromatography-tandem mass spectrometer. Methods The human plasma was extracted with a solid phase extraction(SPE) and determined by UPLC-MS/MS. LC-MS/MS was performed in ESI source with MRM mode for quantification. Results The lowest detectable limit was 0.05ng/mL, the linear range was 1~100ng/mL. The absolute recovery was more than 78.1%. The intra- and inter day precision was within 15% at three concentrations. Conclusion Since the procedure proved to be simple, quick and effective, it could be used for the determination of dexamethasone in human plasma.

Compounds with serotonin reuptake inhibition/5-HT(1A) dual activity were used to build 3D pharmacophore model as a training molecules by Discover Studio. Based on the model, 8 novel aryl piperazine benzo[b][1,4] oxazine derivatives were designed and synthesized, and their structures were confirmed by 1H NMR and HR-MS. Biological evaluation illustrated that compounds VI(1) and VI(7) showed potent functional activities at both 5-HT transporter and 5-HT(1A) receptor, which can be used as lead compounds to guide future research of design and synthesis of potent novel compounds.