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<br>Display Omitted<br>• 4′-Carbonyl chloride rosamine was synthesized and used for NTs by UHPLC-MS/MS. • <b>In situ</b> UA-DDLLME was reported for the simultaneous determination of AANTs and MANTs. • The method was sensitive, selective, low matrix effect, speedy and eco-friendly. • A new analytical tool in diagnosis of AD-related disease.<br>Neurotransmitters (NTs) may play an important role in neurodegenerative disorders such as Alzheimer’s disease (AD). In order to investigate the potential links, a new simple, fast, accurate and sensitive analytical method, based on <b>in situ</b> ultrasound-assisted derivatization dispersive liquid-liquid microextraction (<b>in situ</b> UA-DDLLME) coupled with ultra high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS), has been developed and validated. The quantitation of amino acid neurotransmitters (AANTs) and monoamine neurotransmitters (MANTs) in urine of AD rats were performed in this work. The <b>in situ</b> UA-DDLLME procedure involved the rapid injection of the mixture of low toxic 4-bromoanisole (extractant) and acetonitrile (dispersant), which containing the new designed and synthesized 4′-carbonyl chloride rosamine (CCR) as derivatization reagent, into the aqueous phase of real sample and buffer. Under the selected conditions, the derivatization and microextraction of analytes were simultaneously completed within 1 min. Good linearity for each analyte (R > 0.992) was observed with low limit of detections (LODs, S/N > 3). Moreover, the proposed method was compared with direct detection or other reported methods, and the results showed that low matrix effects and good recoveries results were obtained in this work. Taken together, <b>in situ</b> UA-DDLLME coupled with UHPLC-MS/MS analysis was demonstrated to be a good method for sensitive, accurate and simultaneous monitoring of AANTs and MANTs. This method would be expected to be highly useful in AD diseases’ clinical diagnostics and may have potential value in monitoring the efficacy of treatment.
In an effort to discover potent VEGFR-2 inhibitors, a series of 2,4 or 4,6-disubstituted <b>O</b>-linked indoles derivatives were designed and synthesized. The structural activity relationships led to identification of a potential VEGFR-2 inhibitor compound <b>18</b>.<br>Inhibition of VEGFR-2 signaling pathway has already become one of the most promising approaches for the treatment of cancer. In this study, we describe the design, synthesis, and biological evaluation of a series of <b>O</b>-linked indoles as potent inhibitors of VEGFR-2. Among these compounds, <b>18</b> showed significant anti-angiogenesis activities <b>via</b> VEGFR-2 in enzymatic proliferation assays, with IC50 value of 3.8 nmol/L. Kinase selectivity profiling revealed that <b>18</b> was a multitargeted inhibitor, and it also exhibited good potency against VEGFR-1, PDGFR-<b>α</b> and <b>β</b>.
Purpose: To develop an ultra-high performance liquid chromatography (UPLC) - photodiode array (PDA) method to compare the chemical composition of two different medicinal components of Pterocephalus hookeri. Methods: Samples were chromatographically separated in succession using Waters Acquity UPLCR BEH C18 column (2.1 × 100 mm, 1.7 µm) and gradient elution (0.2% phosphoric acid aqueous - acetonitrile). Using partial least squares discriminant analysis and one-way analysis of variance, attempts were made to distinguish different medicinal parts of P. hookeri. Results: Regression equation for 10 compounds showed good linear regression (R² > 0.9994). The relative standard deviations of precision, stability, repeatability and recovery were under 5%. Compared with the aerial plant part, the root had significantly higher levels of sylvestroside I (p < 0.01), cantleyoside (p < 0.001), dipsanosides B (p < 0.01) and dipsanosides A (p < 0.01), but significantly lower levels of loganic acid (p < 0.001), chlorogenic acid (p < 0.01), and isochlorogenic acid (p < 0.01). There were no significant differences between loganin, sweroside and isochlorogenic acid C. Conclusion: The described method is simple, accurate and reproducible, and can be used for the simultaneous determination of 10 major compounds of P. hookeri. The results demonstrate that there is variation in the chemical composition of the aerialpart and root of P. hookeri and that loganic acid and cantleyoside are the primary chemical biomarkers.