Ultraperformance convergence chromatography is an environmentally friendly analytical technique for dramatically reducing the use of organic solvents compared to conventional chromatographic methods. In this study, a rapid and sensitive ultraperformance convergence chromatography method was firstly established for quantification of thymol and carvacrol, two positional isomers of a major bioactive in the volatile oil of Thymi herba, the dried leaves and flowers of Thymus mongolicus or Thymus przewalskii, known in China as “Dijiao.” Using a Trefoil^TM CEL1 column, thymol and carvacrol were separated in less than 2.5 min and resolution was enhanced. The method was validated with respect to precision, accuracy, and linearity according to the National Medical Products Administration guidelines. The optimized method exhibited good linear correlation (r = 0.9998−0.9999), excellent precision (relative standard deviations (RSDs) < 1.50%), and acceptable recoveries (87.29–102.89%). The limits of detection for thymol and carvacrol were 1.31 and 1.57 ng/L, respectively, while their corresponding limits of quantification were 2.63 and 3.14 ng/L. Finally, the quantities of the two compounds present in 16 T. mongolicus and four T. przewalskii samples were successfully evaluated by employing the developed method. It is hoped that the results of this study will serve as a guideline for the quality control of Thymi herba.

A simple and effective method for the simultaneous quantitative analysis of six caffeoylquinic acids (CAs) in Matricaria chamomilla L. (M. chamomilla) using high-performance liquid chromatography (HPLC) with diode-array detection (DAD) was established. The chromatographic separation was performed on a Waters XBridge Shield RP C₁₈ column (4.6 mm × 250 mm, 5 μm) with the mobile phase of acetonitrile (0.5% phosphoric acid) and water (0.5% phosphoric acid) using a gradient elution at a flow rate of 1.0 mL/min and UV detection at 327 nm. The correlation coefficients of all analytes were 0.999, and the results showed excellent linearity. The lower limits of detection (LLOD) and quantification (LLOQ) of all analytes fall within the range of 0.014∼0.017 μg/mL and 0.068∼0.086 μg/mL, respectively. The extraction recoveries of all analytes fall within the range of 100.74%∼101.55%, with relative standard deviation not exceeding 2.83%. The intraday and interday precisions fall within the range of 0.03%∼0.65% and 0.02%∼0.09%, respectively. This validated method was successfully applied to the investigation of 34 samples of M. chamomilla collected from different geographical areas. The results showed that the established method is appropriate for the analysis of the six CAs in M. chamomilla and helpful for quality assessment of capitula of M. chamomilla (CMC), whole herb of M. chamomilla (WHMC), and related herbal formulas.

Catalyst- and additive-free reactions for synthesizing valuable organic compounds have garnered significant attention in the context of sustainable development. As crucial structural motifs, allylic sulfones find extensive applications in pharmaceutical development and organic synthesis. Despite remarkable advances in allylic sulfone construction, catalyst-free and additive-free methodologies remain an underexplored frontier. Herein, we present an environmentally benign and atom-economical approach for synthesizing allylic sulfones by reacting electron-rich aryl-1,3-dienes with sulfinic acids, achieving yields of 10–94%. This transformation proceeds under ambient air at room temperature, eliminating the need for catalysts or additives. The protocol demonstrates exceptional regio- and chemo-selectivity, streamlined operational simplicity, and excellent scalability potential. This methodology establishes a sustainable and cost-effective paradigm for allylic sulfone synthesis, aligning with green chemistry principles.