1‐(9H‐Fluoren‐9‐ylidene)‐2,3‐dihydro‐2‐methyl‐1H‐benz[e]indene (short as FMB) as one of second‐generation light‐driven molecular motors contains a chiral carbon atom, and has attracted considerable attentions due to macroscopic chiral structures and light‐driven behaviors through supramolecular assembly and cooperative effects. Herein, chiral analysis and semi‐preparative separation of FMB enantiomers have been studied by high‐performance liquid chromatography (HPLC) on polysaccharide‐derived chiral stationary phases (CSPs). Effects of factors on chiral separation of FMB enantiomers, including type of CSP, composition and ratio of mobile phase, temperature, and flow rate, have been discussed in detail. Best separation of racemic FMB was achieved on cellulose tri(3,5‐dimethylphenylcarbamate)‐coated CSP with the resolution of 2.50 using the hexane–ethanol mixture (99:1, v/v). Then, each FMB enantiomer was obtained through semi‐preparative separation with enantiomeric purity over 99%, and their absolute configurations as well as elution order were determined by electronic circular dichroism spectroscopy. Surprisingly, elution reversal phenomenon of FMB enantiomers was observed on cellulose‐ and amylose‐ tri(3,5‐dimethylphenyl carbamate)‐coated CSPs, in which ( S )‐FMB was eluted first on cellulose tri(3,5‐dimethylphenylcarbamate)‐coated CSP, and ( R )‐enantiomer was eluted first on the other. Moreover, molecular docking simulation has been employed to explain the recognition mechanism and elution reversal of FMB enantiomers on these two CSPs. The docking results revealed that π–π stacks, π–lone pair interactions, π– σ, and π–alkyl interactions between FMB and CSPs were the primary forces driving chiral separation, and the differences between them led to the enantiomer elution reversal on these two CSPs. Briefly, this work would provide valuable information for the separation and elution mechanisms of chiral molecular motors on polysaccharide‐based CSPs.

The investigation of helical coordination polymers (CPs) with integrated molecular and mesoscale chirality as high-performance liquid chromatography (HPLC) chiral selectors is a crucial endeavor. Nevertheless, the related study has not been reported. Herein, we prepared a set of CPs that exhibited distinct morphologies, including nanofiber, twist ribbon, and superhelix with varying helical pitches. Subsequently, a series of new chiral stationary phases (CSPs) based on these chiral CPs were successfully fabricated by coating them onto the spherical aminated silica gel matrix. A systematic investigation into the separation performances of these CSPs was conducted via HPLC. By comparing the relationship between chiral CPs with different morphologies and their chromatographic separation abilities, we found that the superhelix possessing both molecular and mesoscale chirality exhibited the most superior chiral separation performance, capable of efficiently resolving nine racemic compounds with a maximum resolution of 3.62. However, the CSPs prepared from chiral CPs with nanofiber or twist ribbon morphologies displayed comparatively poor chromatographic separation abilities. Meanwhile, the chiral separation performance was markedly diminished for the dehelical polymer obtained through the thermal treatment of the superhelix, underscoring that mesoscale superhelical chirality is crucial for chiral recognition and separation. Additionally, we also found that the pitch sizes of the mesoscale superhelices have a significant internal connection with their chiral separation performances. This work not only identifies hierarchical chiral CPs with dual molecular and mesoscale helical chirality as promising chiral materials for chromatographic enantioseparation but also establishes that the introducing mesoscale superhelices and controlling their pitches precisely are key to boosting chiral separation efficiency.

1-(9H-Fluoren-9-ylidene)-2,3-dihydro-2-methyl-1H-benz[e]indene (short as FMB) as one of second-generation light-driven molecular motors contains a chiral carbon atom, and has attracted considerable attentions due to macroscopic chiral structures and light-driven behaviors through supramolecular assembly and cooperative effects. Herein, chiral analysis and semi-preparative separation of FMB enantiomers have been studied by high-performance liquid chromatography (HPLC) on polysaccharide-derived chiral stationary phases (CSPs). Effects of factors on chiral separation of FMB enantiomers, including type of CSP, composition and ratio of mobile phase, temperature, and flow rate, have been discussed in detail. Best separation of racemic FMB was achieved on cellulose tri(3,5-dimethylphenylcarbamate)-coated CSP with the resolution of 2.50 using the hexane-ethanol mixture (99:1, v/v). Then, each FMB enantiomer was obtained through semi-preparative separation with enantiomeric purity over 99%, and their absolute configurations as well as elution order were determined by electronic circular dichroism spectroscopy. Surprisingly, elution reversal phenomenon of FMB enantiomers was observed on cellulose- and amylose- tri(3,5-dimethylphenyl carbamate)-coated CSPs, in which (S)-FMB was eluted first on cellulose tri(3,5-dimethylphenylcarbamate)-coated CSP, and (R)-enantiomer was eluted first on the other. Moreover, molecular docking simulation has been employed to explain the recognition mechanism and elution reversal of FMB enantiomers on these two CSPs. The docking results revealed that π-π stacks, π-lone pair interactions, π- σ, and π-alkyl interactions between FMB and CSPs were the primary forces driving chiral separation, and the differences between them led to the enantiomer elution reversal on these two CSPs. Briefly, this work would provide valuable information for the separation and elution mechanisms of chiral molecular motors on polysaccharide-based CSPs.

Introducing macropores within chiral covalent organic frameworks (COFs) offers a potent solution to the low-efficiency mass transport common in micro- and mesoporous chiral COFs. Nevertheless, this attempt remains untapped to date. Here, we report the first hierarchically macro-mesoporous chiral COF, termed macro-L-DTPC-TP, using a template-assisted approach. Through this strategy, a beta-ketoenamine-linked chiral COF bearing pyrrolidine moieties was assembled around monodisperse polystyrene (PS) nanospheres (similar to 200 nm), during which in situ deprotection of the tert-butoxycarbonyl (Boc) group occurred. Subsequent removal of the PS template produced macro-L-DTPC-TP COF with high crystallinity, macro-mesoporous structure, and inherent chiral pyrrolidine sites. The introduction of interconnected meso- and macropores significantly improved the catalytic efficiency of COF in the aqueous asymmetric aldol reaction. Compared to the pristine mesoporous L-DTPC-TP COF (51% yield), macro-L-DTPC-TP COF exhibited a remarkably high yield of 98%, underscoring the pivotal role of macropores in enhancing mass transport and substrate accessibility. This work presents the first example of a hierarchically macro-mesoporous chiral COF and establishes macropore incorporation as an effective strategy to overcome diffusion limitations and advance the performance of COF-based asymmetric catalysis.

The development of a chiral stationary phase (CSP) based on new matrices is still necessary because of the rapid growth of new chiral drugs and the limitations of the silica gel matrix. For the first time, MOF glass agZIF-62 was used as a matrix to fabricate a chiral stationary phase (CSP) by coating cellulose-tris(3,5dimethylphenylcarbamate) (CDMPC). These MOF glass-based CSPs can separate various racemic compounds, including metalaxyl, epoxiconazole, TSO, cis-metconazole, and triticonazole with resolution values (Rs) ranging from 1.22 to 4.58 and separation factors (alpha) ranging from 1.8 to 6.79. In addition, the HPLC enantiomer separation performances of MOF glass-based and MOF crystal-based CSPs were compared.

Supercritical fluid chromatography (SFC)-based chiral separation has been considered as one of the green, highly efficient, and precise methods for the resolution of new chiral pharmaceuticals. Herein, a comparative study of chiral separation of afoxolaner on polysaccharide-based chiral stationary phases (CSPs) by SFC and high-performance liquid chromatography (HPLC) has been conducted. First, effects of chromatographic conditions on chiral separation of afoxolaner by SFC, including CSPs, modifier types and ratios, flow rate, column temperature, and back pressure, have been discussed in detail. Cellulose tris(4-methylbenzoate)-coated CSP demonstrated the best separation performance for afoxolaner by SFC with the resolution of 2.37 among five CSPs. Afoxolaner enantiomers were eluted at 3.53 min and 4.54 min under the optimized SFC conditions, respectively, and the total analysis time was less than 6 min, much shorter than that by HPLC. Subsequently, molecular docking studies revealed that hydrogen bonds and halogen bonds formed by afoxolaner and CSPs dominated the selective interaction for the separation of afoxolaner. Additionally, hydrophobic effects and π-π stacks between afoxolaner and chiral selectors enhanced the resolution of afoxolaner. Moreover, quantitative determination results of afoxolaner by SFC showed good linearity relationships (R2 > 0.999) between concentration of enantiomers and the corresponding chromatographic peak area in the range from 0.025 to 0.800 mg/mL, and the limit of quantification of enantiomers was 0.025 mg/mL. In brief, SFC separation would offer a green alternative to overcome potential technical bottlenecks in the resolution of new chiral pharmaceuticals.

New rigid, stable, crystalline macrocyclic gem -diols were synthesized, and their stability was found to depend on ring size: the gem -diol form is favored in smaller rings, whereas the diketone form is more stable in larger ones.

The adsorption, degradation, and sensing of chemical warfare agents are highly important. In this work, a new Zr(iv)-based metal-organic gel (MOG) was designed and synthesized, which demonstrated dual-functional performance in the degradation of nerve agent simulants and the adsorptive sensing of blister agent simulants. A Zr(iv)-based MOG, namely, Zr-MOG-taBDC (H2taBDC = 2-(1H-1,2,4-triazol-1-yl) terephthalic acid), was synthesized through the thermal transformation of a tetrahedral Zr(iv)-based metal-organic cage, {[Cp3Zr3(mu 3-O)(mu 2-OH)3]4(taBDC)6}(Cl-)4 (Zr-MOC-taBDC), in a mixed acetonitrile/water solvent system, bypassing the need for tedious anion exchange and high-boiling solvents. The resulting MOG exhibited hierarchical porosity and high stability across a wide pH range (1-11). Catalytic tests revealed that Zr-MOG-taBDC achieved 95.4% degradation efficiency for the nerve agent simulant diethyl phenylphosphonate (DEPPT), with a half-life of 49.5 minutes, outperforming its crystalline MOC precursor. Additionally, the gel demonstrated a high adsorption capacity (0.6 g g-1) for the mustard gas simulant 2-chloroethyl ethyl sulfide (CEES), enabling real-time detection via a quartz crystal microbalance (QCM) with a linear response range up to 100 ppm. Mechanistic studies indicated that degradation proceeds via P-S bond cleavage catalyzed by Zr-OH-H2O Lewis acid-base sites, whereas adsorption involves reversible physical and irreversible chemical interactions with triazole groups and Zr-oxo clusters. This work highlights the potential of Zr-MOGs as multifunctional materials for chemical warfare agent mitigation and sensing.

Chiral covalent organic frameworks (COFs) have been intensively studied in asymmetric catalysis. Despite various strategies to boost catalytic efficiencies, the impact of tuning the dimensionality of chiral COFs on their catalytic performance has yet to be explored. Herein we demonstrate for the first time that regulating the dimensionality of chiral COFs can significantly improve their asymmetric catalytic efficiency. By rationally designing two positional isomers of amino chiral building blocks and condensing them with a D2h-symmetric aldehyde monomer via Schiff-base condensation, we successfully prepared two chiral imine-linked COFs with distinct dimensional isomerism: one with a 1D chain-like topology and the other with a 2D layered topology. The distinction in the dimensionality of the two chiral COFs led to notable differences in their catalytic efficiencies for asymmetric aldol condensation. The 1D chiral COF exhibited almost twice the catalytic activity of the 2D counterpart, albeit the nearly identical stereoselectivity of the products. This dimensional isomerism regulation strategy not only expands the topological diversity of chiral COFs but also paves a new avenue for enhancing their asymmetric catalytic performance.

A new Cd(II) coordination polymer (CP) based on (3,3 '-(4-(4-(1H-imidazol-1-yl)phenyl)pyridine-2,6-diyl) dibenzoic acid (H2IPPDA), namely, [Cd(IPPDA)(H2O)]n(Cd-IPPDA), was constructed. It exhibits a twodimensional coordination network with a (4 & sdot;82) topology, and the 2D networks are packed into a 3D supra-molecular framework via hydrogen bonds. Interestingly, Cd-IPPDA is capable of absorbing iodine molecules with a capacity of 3.4 g/g, although it has no significant pores in the framework. A mechanistic study revealed that the strong interactions between the iodine molecules and the framework cause the transformation from crystalline nonporous to porous amorphous structures. The resulting porous amorphous network, namely, a-Cd-IPPDA, still showed good iodine adsorption performance. It's capacity was 3.0 g/g but adsorption kinetics significant increased, and could be reused for at least five cycles without a significant capacity decrease. In addition, the luminescence intensity of Cd-IPPDA was quenched by tetracyclines (TCs) in water; thus, this material can be used as a sensor for detecting TCs. The detection limits for OXY, CTE, and GEN are 0.51, 0.93, and 0.42 mu mol/L, respectively. Moreover, the detection selectively is also good. The internal filtering effect and fluorescence resonance effect contribute to fluorescence quenching.

Nowadays, water pollution caused by organic dyes has received increasing attentions due to serious harm to public health and ecosystem, and it is of great significance to design new porous materials with high adsorption capacity to remove organic dye pollutants from wastewater. Herein, a new two-dimensional N-rich imine-linked covalent organic framework (termed as BPA-TAPA COF) has been constructed through Schiff-base reaction between 2,2'-bipyridine-5,5'-dicarboxaldehyde (BPA) and tri(4-aminophenyl)amine (TAPA) under solvothermal conditions, and showed good crystallinity, high thermal stability and certain porosity. Then, it was used as a functional adsorbent for removal of organic dyes, which exhibited good adsorption performances for both cationic and anionic dyes, namely malachite green (MG), Janus green B (JGB), Congo red (CR), and acid orange (AO). Significantly, the adsorption capacities of BPA-TAPA COF for MG and CR reached up to 1070 and 2016 mg.g(-1), in which the latter ranked as the highest in comparison to those of the other documented functional COFs. The removal efficiency of BPA-TAPA COF toward CR (100 ppm) in aqueous solution reached to 99.0% within 180 min. Hydrogen bonds and pi-pi stacking attractions between COF and dye molecules played crucial roles in adsorption of organic dyes. This work uncovers that neutral COFs with nitrogen-rich functional sites can be used as new adsorbents for removal of both cationic and anionic organic dyes and might provide new information for developing effective adsorbents with high adsorption capacity.

Candesartan cilexetil (CC) is one of well-tolerated antihypertensive drugs, while its poor solubility and low bioavailability limit its use. Herein, two mesoporous silica (Syloid XDP 3150 and Syloid AL-1 FP) and the corresponding amino-modified products (N-XDP 3150 and N-AL-1 FP) have been selected as the carriers of Candesartan cilexetil to prepare solid dispersion through solvent immersion, and characterized through using powder X-ray diffraction analysis, infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, and solid-state nuclear magnetic resonance spectroscopy, etc. The state of CC changed from crystalline to amorphous after loading onto the silica carriers, in which no interactions between CC and silica existed. Then, the dissolution behaviors in vitro were studied through using flow-through cell dissolution method. CC-XDP 3150 sample exhibited the most extensive dissolution, and the cumulative release of CC from it was 1.88-fold larger than that of CC. Moreover, the pharmacokinetic results in rats revealed that the relative bioavailability of CC-XDP 3150 and CC-N-XDP 3150 solid dispersions were estimated to be 326 % % and 238 % % in comparison with CC, respectively. Clearly, pore size, pore volume, and surface properties of silica carrier have remarkable effect on loading, dissolution and bioavailability of CC. In brief, this work will provide valuable information in construction of mesoporous silica-based delivery system toward poorly water-soluble drugs.

Volatile organic compounds(VOCs) are considered as one of the major components in atmospheric pollutants, and pose serious hazards to both human health and the environment. It is urgent to develop new highefficient detection techniques for VOCs. In this work, ethylenediamine(ED) and ethanolamine(EA) were grafted into MIL -101(Cr) to obtain ED - and EA -derived MIL -101(Cr) materials[labeled as MIL -101(Cr) -ED and MIL -101 (Cr ) -EA ], respectively. Then , these three MIL -101 (Cr ) materials were loaded on the surface of quartz crystal through dip coating to assemble three kinds of MIL -101 (Cr ) -modified quartz crystal microbalance (QCM ) gas sensors , respectively. Moreover , the sensing and recognition performance of these QCM sensors toward methanol , ethanol , 2 -propanol , acetone , cyclohexane , diethylamine , formic acid , formaldehyde , ammonia , and acetic acid were studied in detail. As indicated , MIL -101 (Cr ) -ED - and MIL -101 (Cr ) -EA -loaded QCM sensors showed better sensing performance for formic acid in comparison with the original MIL -101 (Cr ) -based sensor , and the oscillation frequency of these two sensors decreased by -375.6 and -232.1 Hz when the concentration of formic acid was 350 mg/L , respectively. Delta f value was linearly related to the concentration of formic acid in the range of 5 - 350 mg/L. In addition , the sensitivity of MIL -101 (Cr ) -ED -loaded QCM gas sensor was estimated to be 0.95 Hz L mg -1 and the limit of detection was 0.95 mg/L. As a result , this MIL -101 (Cr ) -modified QCM gas sensor demonstrated high sensitivity , low detection limit , and good repeatability. In brief , this research would provide some useful information for developing new QCM gas sensors in real -time VOCs detection.

Pores are generally important for coordination polymers (CPs) to realize adsorption functions, while the high-capacity uptake of guest molecules by nonporous CPs is still very rare. Herein, we demonstrate an...

Paclobutrazol is a plant growth inhibitor widely used in agricultural production. However, toxicology studies of paclobutrazol enantiomers towards aquatic organisms are limited. Herein, effects of paclobutrazol and its two enantiomers (2R, 3R; 2S, 3S) on glycolipid metabolism of zebrafish have been systemically explored at the concentration of 10 mg/L through biochemical analyses, LC-MS/MS, molecular dynamics simulation, and gene expression. In all treatments, the contents of glucose, citric acid and lactate significantly were increased while the glycogen and pyruvate contents were decreased, in which (2R, 3R)-paclobutrazol exhibited a greater effect than the (2S, 3S)-enantiomer (P < 0.05). Then, activities of hexokinase and lactate dehydrogenase in (2R, 3R)-paclobutrazol treatment were 0.74- and 1.18-fold higher than (2S, 3S)-enantiomer treatment, respectively (P < 0.001), and the results of molecular dynamics simulation revealed that the binding free energy of hexokinase 1 to (2R, 3R)-paclobutrazol was higher than that to the antipode. Moreover, lipids including triglycerides, total cholesterol, fatty acids, bile acids and glycerophospholipids in zebrafish were strikingly affected after paclobutrazol exposure. The (2R, 3R)-paclobutrazol-treated group showed the most obvious changes, indicating that it possessed much stronger disruption ability on the lipid metabolism of zebrafish. Furthermore, qRT-PCR analysis results revealed that (2R, 3R)-enantiomer significantly impacted expressions of glycolipid metabolism-related genes (hk1, g6pc, pck1, pk, aco, cebpa, cyp51, fasn and ppara) in zebrafish than (2S, 3S)-enantiomer (P < 0.05). Briefly, this study provides new evidences for the toxicity of paclobutrazol to aquatic organisms and the potential risk to human health at the chiral level.

The development of new dual-functional materials for detection and removal of heavy metal ions is of great significance in environmental protection. Herein, a new amine-functionalized beta-ketoenamine-linked covalent organic framework (termed as NH2-Th-Tfp COF) containing rich O,N,O'-chelating sites and free amine groups has been synthesized through the site-selective synthesis strategy under solvothermal conditions. The as-synthesized NH2-Th-Tfp COF shows strong fluorescence in water dispersion and can be used as highly sensitive and selective fluorescent probe for Cu2+ detection. As a sensing platform, the limit of detection for NH2-Th-Tfp COF toward Cu2+ ion is estimated to be 0.19 mu M. Besides, the NH2-Th-Tfp COF possesses high adsorption capacity of 153 mg/ g toward Cu2+ ion in aqueous solution. More importantly, this NH2-Th-Tfp COF exhibits higher sensitivity and larger adsorption capacity toward Cu2+ ion in comparison with the non-amine functionalized Th-Tfp COF, which may be attributed to the large number of free amine groups in the pore walls of NH2-Th-Tfp COF. The coordi-nation interactions between Cu2+ ion with the O, N, O'-chelating sites and free amine groups in the pore walls of NH2-Th-Tfp COF can greatly enhance its recognition and absorption performances toward Cu2+ ion, as verified by X-ray photoelectron spectroscopy. This work may pave the way for designing new fluorescent COF materials with dual functions for simultaneous detection and removal of specific metal ions.

The development of new techniques for the detection of microRNAs (miRNAs) is highly desirable. Herein, a new crystalline three-component covalent organic framework (COF) termed EB-TAPB-TFP COF was synthesized under solvothermal conditions utilizing 1,3,5-triformylphloroglucinol, 1,3,5-tris(4-aminophenyl)benzene and ethidium bromide as monomers. Interestingly, EB-TAPB-TFP COF can be self-exfoliated into two-dimensional nanosheets (NSs) in an aqueous medium. The obtained EB-TAPB-TFP NSs exhibited a remarkable fluorescence intensity enhancement in the presence of a DNA-miRNA heteroduplex when compared to the presence of single-stranded DNA and other phosphate-based small molecules, making it promising in the detection of miRNA without tagging any fluorescent marker. Moreover, the EB-TAPB-TFP NSs can also be used as sensing material for the detection of a DNA-miRNA heteroduplex using the quartz crystal microbalance technique, which is in good agreement with the fluorescence sensing result. The exploration of COF-based sensors in this work demonstrates a new pathway for the selective detection of miRNAs.

Despite significant progress on the design and synthesis of covalent organic frameworks (COFs), precise control over microstructures of such materials remains challenging. Herein, two chiral COFs with well-defined one-handed double-helical nanofibrous morphologies were constructed via an unprecedented template-free method, capitalizing on the diastereoselective formation of aminal linkages. Detailed time-dependent experiments reveal the spontaneous transformation of initial rod-like aggregates into the double-helical microstructures. We have further demonstrated that the helical chirality and circular dichroism signal can be facilely inversed by simply adjusting the amount of acetic acid during synthesis. Moreover, by transferring chirality to achiral fluorescent molecular adsorbents, the helical COF nanostructures can effectively induce circularly polarized luminescence with the highest luminescent asymmetric factor (glum ) up to ≈0.01.

Chiral triazole pesticides may cause enantioselectively adverse effects to non-target organisms. In this work, we employed zebrafish as an aquatic organism model to explore stereoselective acute toxicity, bioaccumulation, oxidative stress, and thyroid disruption of cis-metconazole enantiomers. The median lethal concentration values of (1S, 5R)-metconazole, (1R, 5S)-metconazole, and the mixture of them against zebrafish were 4.01, 2.61 and 3.17 mg???L- 1, respectively. (1R, 5S)-Metconazole was preferentially bioaccumulated in zebrafish than (1S, 5R)metconazole, and the bioconcentration factor of (1R, 5S)-metconazole was 1.28-fold larger than that of (1S, 5R)metconazole. Then, the activity order of catalase, superoxide dismutase, and glutathione-S transferase enzymes in zebrafish was expressed as (1S, 5R)-metconazole > the mixture > (1R, 5S)-metconazole, while the order of malondialdehyde content in zebrafish was (1R, 5S)-metconazole > the mixture > (1S, 5R)-metconazole. Moreover, cis-metconazole exhibited enantioselective regulation effects on the levels of triiodothyronine and thyroxine in zebrafish, and (1R, 5S)-metconazole possessed stronger thyroid disruption ability to zebrafish than the others. By virtue of molecular docking methodology, the binding affair and docking energy results supported that interactions between (1R, 5S)-metconazole and thyroid hormone receptors were much stronger than those between (1S, 5R)-metconazole and same receptors. This study of enantioselective evaluation of cis-metconazole in zebrafish can provide favorable information for risk assessments of chiral pesticides toward environment and health of aquatic organisms.

The enantioselective toxicity of triticonazole (TRZ) to non-target organisms, the effect on wheat growth and quality, and the environmental fate of TRZ were investigated systematically in this study. The acute toxicity of S-TRZ to non-target aquatic and terrestrial organisms was greater than that of rac-TRZ and R-TRZ. The S-enantiomer significantly inhibited the growth and lodging resistance of wheat. S- and R-TRZ not only reduced the grain yield but also inhibited the activities of ADP-glucose pyrophosphorylase (AGPase) and starch synthase. The results of homology modeling and molecular docking further showed that the inhibition of AGPase activity by the two enantiomers hindered the accumulation of starch. By contrast, the racemate promoted the growth and development of wheat and improved grain quality. And the half-lives of the racemate in stems, grains, leaves, and soils were shorter than those of the enantiomers. The results of risk quotient (RQ) values showed that the application of TRZ enantiomers during wheat planting would bring a higher potential dietary risk to Chinese consumers. In comprehensive consideration of these results, the application of the racemate may be safer and more reasonable at the flowering stage of wheat.