Build a bridge: The first catalytic intramolecular [3+2] cycloaddition of monodonor-monoacceptor cyclopropanes (see scheme) provides general and efficient strategy for construction structurally diverse acetal[n.2.1] 1,4-dioxygen-substituted cyclic skeletons, which are widely distributed in biologically important natural products.

Abstract Introduction Quisqualis indica L. (QIL) has a long history as traditional Chinese herb in China, but the study of volatile components QIL from different geographical sources been relatively rare. Objectives To establish an optimal headspace gas chromatography–mass spectrometry (HS‐GC‐MS) method to comprehensively analyse component profile and screen quality markers origins. Methods Response surface methodology (RSM) was used optimise conditions for analysis. The four main origins...

The aim of this study is to establish a rapid and convenient microwave-assisted digestion method for sample pretreatment evaluate amino acids in Chebulae fructus (CF). microwave was optimized extract from CF, the differences CF different origins processing states were analyzed evaluated. influences temperature, time, liquid-material ratio on extraction effect investigated by sing factor test response surface (RSM), conditions optimized. contents 17 determined an automatic acid analyzer....

An efficient ambient temperature post-column oxidation system was developed for high-performance liquid chromatography online coupled with cold vapor atomic fluorescence spectrometry mercury speciation analysis in seafood. The does not require an external heat source, such as a hot water bath, microwave heating or UV irradiation, to decompose organomercury compounds into inorganic ion (Hg(II)). Methylmercury (MeHg), ethylmercury (EtHg), phenylmercury (PhHg) and Hg(II) were baseline separated...

To explore the potential molecular mechanism of Pueraria Lobata Radix (RP) and Salviae Miltiorrhizae (RS) in treatment type 2 diabetes mellitus (T2DM) based on network pharmacology docking.The chemical constituents core targets RP RS were searched by Traditional Chinese Medicine System Pharmacology (TCMSP); target genes related to T2DM obtained through GeneCards database, component diagram was constructed, intersection active compounds synthesized, protein-protein interaction (PPI)...

Abstract In this study, we investigated a simple, sensitive and reliable liquid chromatography‐fluorescence detection method for the determination of memantine hydrochloride in rat plasma which was based on derivatization with 9‐fluorenylmethyl chloroformate (FMOC‐Cl). For first time, FMOC‐Cl introduced into plasma. The amino groups amantadine (internal standard) were trapped to form hydrochloride‐FMOC‐Cl compositions, can be very compatible LC‐FLD. Precipitation proteins by acetonitrile...

The aim of the study was to investigated mechanism Strychnos nux-vomica L. (Semen Strychni, SS) against papillary carcinoma thyroid (PTC) by combined network pharmacology and experimental verification. By searching TCMSP, SEA SwissTarget Prediction database, main active ingredients related targets were obtained. Utilizing Venny 2.1.0 String database Cytoscape 3.7.2 screened intersection target constructed protein-protein interaction (PPI) diagram. Using R 4.0.4 software carried out...

This study aims to establish a rapid and convenient microwave-assisted digestion method for sample pretreatment determine amino acid profiles in natural products. was applied analyze the of Quisqualis Fructus (QF) from different planted origins. The conditions were optimized by response surface methodology (RSM), 17 acids origins QF determined an automatic analyzer according conditions. contents further analyzed fingerprint chemometric analysis. temperature microwave at 167 °C, time 24 min,...

A novel method with high sensitivity for the rapid determination of chrysin, apigenin and luteolin in environment water samples was developed by double-pumps controlled on-line solid-phase extraction (SPE) coupled high-performance liquid chromatography (HPLC). In technique, metal organic framework MIL-101 synthesized applied as a sorbent SPE. The as-synthesized characterized scanning electron microscope, X-ray diffraction spectrometry, thermal gravimetric analysis micropore physisorption...

A novel, rapid, and reliable ultra-high performance supercritical fluid chromatography (UHPSFC) method was developed to correctly separate quantitatively determine Sudan dyes in chilli products. The effect of different separation parameters on the retention characteristics investigated. results showed that diode array detection I–II accomplished at 480 nm, III–IV 500 nm. In analysis dyes, whole time less than 10 minutes, had a limit quantification 0.25 μg/mL 0.50 μg/mL, respectively. All...

Qizhi Xiangfu Pills (QXPs) are a traditional Chinese medicine (TCM) used clinically for qi stagnation and blood stasis. The current quality control of QXPs in the ministry standards reported literature is minimal, requires improvement.This study aimed to analyze determine active ingredients its overall evaluation.In this study, quantitative analysis multi-components by single marker (QAMS) method was established simultaneously caryophyllene oxide, cyperotundone, ligustilide, α-cyperone GC....

An effective and comprehensive quality evaluation method for Liuwei Dihuang pills (LDP) was established by the simultaneous determination of 8 active components in LDP quantitative analysis multicomponents single marker (QAMS) high-performance liquid chromatography (HPLC) fingerprint combined with chemometrics. These were determined QAMS external standard (ESM), results two methods compared to validate accuracy feasibility method. showed good linear relationships within their ranges, whose...

A high performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) method was developed for the determination of hexabromocyclododecanes (HBCDs) in ambient air samples. The samples were extracted by Soxhlet extractor with hexane, then purified on composite gel column. At first, interfering substances rinsed 50 mL hexane and 100 hexane-dichloromethane (9:1, v/v), 180 -dichloromethane (4:1, v/v) used to elute targets. compounds separated gradient elution...

Based on high performance liquid chromatography with the diode array detector (HPLC-DAD), a new strategy for simultaneous determination of ten bioactive ingredients in Lianhua Qingwen capsule (LHQW) was developed comprehensive quality assessment LHQW. In this work, rhein regarded as internal reference substance (IRS), relative correction factors (RCFs) neochlorogenic acid, amygdalin, chlorogenic forsythoside A, quercitrin, phillyin, glycyrrhizic isoforsythiaside, and (+)...

Background: N-nitrosodimethylamine (NDMA) are a sort of genotoxic impurities (GTIs) having strong carcinogenic effects and obvious hepatotoxicity. To monitor the NDMA content metformin hydrochloride sustained-release tablets enteric capsules in China from 2018 to 2022, GC-MS/MS method was established validated. Materials Methods: The chromatographic column Agilent VF-WAXms capillary (30 m×0.25 mm, 0.25 μm). equipped with multiple reaction monitoring (MRM) modes. assess quantity NDMA,...