Severe liver injury and clinical characteristics of occupational exposure to 2-amino-5-chloro-N,3-dimethylbenzamide: A case series

Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning in humans.This study aimed to reveal the health hazard of this chemical for humans and summarize the clinical characteristics of patients with occupational 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.Methods:This observational study included four patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning from June 2022 to July 2022.The entire course of the incidents was described in detail.Blood 2-amino-5-chloro-N,3-dimethylbenzamide concentrations were detected by a mass spectrometer.Hema-toxylin and eosin staining was performed to assess liver injury,and immunofluorescence was used to evaluate hepatic mitophagy.Results:The 2-amino-5-chloro-N,3-dimethylbenzamide powder(99%purity)entered the human body mainly via the skin and respiratory tract due to poor personal protective measures.The typical course of 2-amino-5-chloro-N,3-dimethylbenzamide poisoning was divided into latency,rash,fever,organic dam-age,and recovery phases in accordance with the clinical evolution.Rash and fever may be the important premonitory symptoms for further organ injuries.The chemical was detected in the blood of all patients and caused multiple organ injuries,predominantly liver injury,including kidney,myocardium,and micro-circulation.Three patients recovered smoothly after comprehensive treatments,including artificial liver therapy,continuous renal replacement therapy,glucocorticoids,and other symptomatic and supportive treatments.One patient survived by liver transplantation.The postoperative pathological findings of the removed liver showed acute liver failure,and immunofluorescence staining confirmed the abundance of mitophagy in residual hepatocytes.Conclusions:This study is the first to elaborate the clinical characteristics of patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.The chemical enters the body through the respiratory tract and skin during industrial production.The 2-amino-5-chloro-N,3-dimethylbenzamide poisoning causes multiple-organ dysfunction with a predominance of liver injury.Liver transplantation may be an effective option for patients with severe liver failure.The mechanisms of liver injury induced by 2-amino-5-chloro-N,3-dimethylbenzamide might involve abnormal mitochondrial function and mitophagy.

Syntheses and Characterization of Two New Alkaline Earth Metal-organic Topological Frameworks with 3-Amino-1H-1,2,4-triazole-5-carboxylate

Two new alkaline earth metal coordination polymers constructed from the deriva-tive of 1,2,4-triazole are presented herein,namely,{[Sr（AmTAZAc）2（H2O）]}（1） and {[Ba（AmTAZAc）2（H2O）]}（2）（AmTAZAc = 3-amino-1H-1,2,4-triazole-5-carboxylate）,which have been synthesized by using the layering method and structurally characterized by elemental analysis,IR,and single-crystal X-ray diffraction.Complexes 1 and 2 are isostructural,and both crystallize in the orthorhombic system,space group Fdd2.X-ray structural analysis shows that 1 or 2 has an intriguing 3-D infinite network of（318.438.510） topology based on a 2-D sheet structure of（4,4） net.The result shows that noncovalent interactions play an important role in strengthening the whole structures of the compounds.

Role of α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor regulation in stress-induced pain chronification

Persistent postsurgical pain is a serious issue in public health, which has received increased interest in recent years. Previous studies have reported that psychological factors promote the development of chronic postsurgical pain. However, it is unclear how chronification of postsurgical pain occurs. The α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor(AMPA) phosphorylation in the central nervous system plays a critical role in synaptic plasticity and contributes to central sensitization and chronic pain development. Here, we discuss the role of AMPA receptor regulation in stress-induced pain chronification after surgery.

Facile synthesis of[1,2,4]triazino[4,3-b][1,2,4,5]tetrazepin derivatives by a one-pot reactions using 4-amino-3-hydrazinyl-6-methyl-1,2,4-triazin-5(4H)-one

4-Amino-3-mercapto-6-methyl-l,2,4-triazin-5（4H）-one 1 converted to 4-amino-6-methy-3-（methylthio）-1,2,4-triazin-5（4H）-one by methylation with methyl iodide.Controlled hydrazination of the resulting compound afforded 4-amino-3-hydrazinyl-6- methyl-l,2,4-triazin-5（4H）-one 2 as a building block,to the synthesis of some novel derivatives of[1,2,4]triazino- [4,3,b][1,2,4,5]tetrazepine 3-6,by the reaction with 3-chloropentane-2,4-dione,chloro acetonitrile,1,3-dichloroacetone,and methyl bromoacetate.This general synthetic procedure can be extended to the preparation of wide variety of tetrazepines using 1,2- bielectrophiles derivatives.

Theoretical Study on the Reaction Mechanism of 2-Methoxybenzaldehyde,4-Bromo-indanone,Malononitrile and Ammonium Acetate One-pot to Form 6-(2-Methoxyphenyl)-2-amino-6-bromo-5H-indeno[1,2-b]pyridine-3-carbonitrile

The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-（2-methoxyphenyl）-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Reaction pathways were investigated in this study. The result indicates that the reaction Re→ TSB1→IMB1→ TSB2→ IMB2→TSB3→IMB3→TSB4→IMB4→TSB5→IMB5→TSB6→IMB6→TSB7→IMB7→ TSB8→IMB8→TSB9→IMB9→P2 is the main pathway, the activation energy of which is the lowest. The dominant product predicted theoretically is in agreement with the experiment results.

Auxiliary Ligands Mediated One- and Two-dimensional Cd(Ⅱ) Coordination Polymers Incorporating Methyl-3- hydroxy-5-carboxy-2-Thiophenecarboxylate Ligand

Two N-donor ligands mediated Cd（Ⅱ） coordination polymers, namely,[Cd（L）（dmpz）2]n （1） and {[Cd（L）（atr）05（H20）]（H2O）}n （2） （H2L = methyl-3-hydroxy-5-carboxy-2-thiophenecarboxylate, dmpz = 3,5-dimethylpyrazole, and atr= 4-amino-l,2,4-triazole）, havebeen produced. Their structures were characterized by single-crystal X-ray diffraction analysis,elemental analyses and infrared spectra. Compound 1 possesses a one-dimensional （1D） chainstructure and is finally extended into a three-dimensional （3D） supramolecular architecturethough hydrogen bonding interactions. Compound 2 features a two-dimensional （2D） networkwith 4-connected sql topology based on dinuclear Cd（Ⅱ） clusters as nodes, which is alsoassembled into a 3D supramolecular architecture through hydrogen bonding interactions.Furthermore, compounds 1 and 2 exhibit high thermal stabilities and intense fluorescent emissionin the solid, and can be explored as potential luminescent materials.

((3-(3-硅胶丙基)硫基)丙基)硫酸酯作为可回收催化剂用于合成4,4'-芳亚甲基-双(1H-吡唑-5-醇)(英文)

Sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl)ester is employed as a recyclable catalyst for the condensation reaction between aromatic aldehydes and 3-methyl-l-phenyl-5-pyrazolone. This condensation reaction was performed in ethanol under refluxing conditions giving 4,4'-alkylmethylene-bis(3-methyl-5-pyrazolones) in 74-90% yields. The heterogeneous catalyst was recycled and used in eleven runs for the reaction between benzaldehyde and 3-methyl-l-phenyl-5-pyrazolone without losing catalytic activity.

Synthesis, Crystal Structure, Antibacterial Activities and Theoretical Computation of 3-(2-Hydroxybenzly)-4-(4-isopropylbenzyl- ideneamino)-(1H)-1,2,4-triazole-5-thione

The title compound C18H18N4OS has been synthesized by the reaction of 3-（2-hydroxy- benzyl）-4-amino-（1H）-1,2,4-triazole-5-thione with 4-isopropylbenzaldehyde in ethanol and characterized by IR, ^1H NMR spectra and elemental analysis. Its structure was determined by X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 11.605（2）, b = 7.401（1）, c = 20.339（2） A, β= 103.05（2）°, V= 1701.8（4） A^3, Z = 4, Mr = 338.42,μ = 0.202 mm^-1, Dc = 1.321 g/cm^3 and F（000） = 712. The structure was solved by direct methods and refined to R = 0.0428 and wR = 0.1069. Due to the intramolecular O-H…N hydrogen bond and π-π stacking interactions between the benzene （C（1）～C（6）） and triazole rings, the two planes are essentially coplanar. Their biological activities have been measured, showing this type of compound has certain antibacterial activity for Staphylococous aureus and Bacillus subtilis. Based on the quantum chemistry calculation at the RHF/6-31G level, the frontier orbitals and electrostatic potential of the title compound were also discussed.

Synthesis,Crystal Structure and Thermal Properties of Zn（NH3）3（AFT）2

A new coordination compound of Zn(NH3)3(AFT)2(1,ZnC6H13N17O2,AFT =4-amino-3-(5-tetrazolate)-furazan)was synthesized and characterized by elemental analysis and FT-IR spectrum.Its crystal structure was determined by X-ray single-crystal diffraction.This crystal belongs to the orthorhombic system,space group Pnma with a = 18.680(3),b = 6.9438(11),c =12.268(2)A,μ= 1.592 mm-1,V= 1591.3(4)A3,M,= 420.72,Dc=1.756 g·cm^-3,Z= 4,F(000)= 860,the final R = 0.0480 and wR = 0.1262 for the observed reflections with I>2σ(Ⅰ).The zinc(Ⅱ)ion is five-coordinated by N atoms from two AFT"ligands and three NH3 molecules.The thermal decomposition mechanism of compound 1 was tested by differential scanning calorimetry(DSC)and thermogravimetry-derivative thermogravimetry(TG-DTG)methods.The DSC curve exhibits two endothermic and one exothermic processes.In addition,the non-isothermal kinetics parameters were calculated by using the Kissinger s method and Ozawa-Doyle's method.Besides,the entropy of activation(ΔS≠),enthalpy of activation(ΔH≠),free energy of activation(ΔG≠)and impact sensitivity(IS)was also obtained.

Solid State Synthesis and Crystal Structure of 3—Methly—1—phenyl—4—phe

The solid state thermal reaction of benzil with 3-methyl-1-phenyl-5-pyrazolone gave the title compound 1 (C_24H_18N_2O_2) and its isomer 2. The crystal structure of the title compound has been determined by X-ray analysis. The crystal belongs to monoclinic system, space group P2_1/n, with cell parameters a = 7. 479 ( 1 ), b =16. 992(1), c=15. 165(1) A , β= 100. 99(1)°, V= 1891. 9 A￣3, M_r=366. 42, Z=4, D_c= 1. 286 g/cm￣3, μ= 6. 236 cm￣-1, F(000) = 768. In the molecule of 1, benzoyl group and CO group of five-member ring are in cis-positions, the interaction of oxygen atoms leads to the noncoplanarity.

Preparation of 2-amino-5,7-dimethoxy-4-aryl/alkyl-4H-chromene-3-carbonitriles using Na_2O-Al_2O_3-P_2O_5 glass–ceramic system

A highly efficient and environmentally benign protocol for the synthesis of 2-amino-5,7-dimethoxy-4- aryl/alkyl-4H-chromene-3-carbonitrile derivatives by one-pot three-component coupling reacting of aromatic aldehydes, malononitrile and 3,5-dimethoxy phenol under reflux condition has been developed in aqueous EtOH media using Na2O-Al2O3-P2O5 glass-ceramic system.

Methylation of 5-Amino-3-methylthio-1 H-pyrazole Derivatives and Two Related Crystal Structures

5-Amino-3-methylthio-1H-pyrazoles are very important building blocks from which a wide variety of pyrazole de-rivatives can be prepared. When substituted 5-amino-3-methylthio-1H-pyrazole was treated with CH3I, the methy-lation occurres at endocyclic two nitrogens at the same time. The ratio of isomers in products was depended upon the nature of 4-position substituent in the pyrazole ring. The products were characterized by X-ray diffraction analysis, and the ratios of isomer were explained by means of the results of ab inito calculation.

Studies on 3-Amino-4-(1H-tetrazol-5-yl)-furazan:Crystal Structure, Thermal Behavior and Energetic Performance

The structure of 4-amino-3-(5-tetrazolate)-fiirazan(HAFT) was characterized by single crystal X-ray diffraction. The thermal decomposition process of HAFT was investigated by MS-FTIR-DSC-TG coupling technique. The result shows that the exothermic process occurs from 278.7-350℃, with a peak temperature of 324.7℃. The thennal decomposition gaseous products of HAFT are NO2, CO2, HCN, CO, NH3 and H2O. The detonation velocity and detonation pressure of HAFT were calculated by the nitrogen equivalent equation. The detonation velocity of HAFT is 7727.46 m/s, which is higher than that of TNT(7178 m/s). The detonation pressure of HAFT(25.27 GPa) is satisfactory. The sensitivity tests reveal HAFT possesses excellent insensitivities to impact and friction.

Improvement in the synthesis of 2-(5-amino-1,2,4-thiadiazol-3- yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl thioester

2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-(Z)-meth-oxyiminoacetic acid 2-benzothiazolyl thioester(III),an important intermediate of the fourth generation cephalos-porins,was efficiently synthesized by reacting 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid(I)with 2,29-dibenzothiazole disulfide(II)in the presence of triphenylphosphine.Effects of reaction time,temperature,solvents,catalysts and feeding molar ratio on the yield and quality of products were investigated,and an im-proved procedure suitable for industrial production was established.Using 1,2-dichloroethane as solvent,triphe-nylphosphine as reducer,and triethylamine as catalyst,n(I):n(II):n(triphenylphosphine)51.0:1.0:1.0,the product was obtained at room temperature in 98.1%yield.The purity of the product without further purification is 98.7%determined by HPLC method.This procedure could be a suitable alternative to the traditional processes because of its easy handling,high yield and low cost.

α-氨基羟甲基噁唑丙酸受体与听觉神经系统

α氨基羟甲基噁唑丙酸(AMPA)受体是脊柱动物中枢神经系统一类主要的兴奋性神经递质受体,在中枢神经系统的信号传导、神经发育以及突触的可塑性等方面都起着至关重要的作用。本文阐述了AMPA受体在听觉神经系统中的分布、生物学特征及和它在听觉神经系统发育、突触传递过程中所起的作用。

Modified constraint-induced movement therapy alters synaptic plasticity of rat contralateral hippocampus following middle cerebral artery occlusion

Modified constraint-induced movement therapy is an effective treatment for neurological and motor impairments in patients with stroke by increasing the use of their affected limb and limiting the contralateral limb.However,the molecular mechanism underlying its efficacy remains unclear.In this study,a middle cerebral artery occlusion(MCAO)rat model was produced by the suture method.Rats received modified constraint-induced movement therapy 1 hour a day for 14 consecutive days,starting from the 7^th day after middle cerebral artery occlusion.Day 1 of treatment lasted for 10 minutes at 2r/min,day 2 for 20 minutes at 2 r/min,and from day 3 onward for 20 minutes at 4 r/min.CatWalk gait analysis,adhesive removal test,and Y-maze test were used to investigate motor function,sensory function as well as cognitive function in rodent animals from the 1st day before MCAO to the 21^st day after MCAO.On the 21^st day after MCAO,the neurotransmitter receptor-related genes from both contralateral and ipsilateral hippocampi were tested by micro-array and then verified by western blot assay.The glutamate related receptor was shown by transmission electron microscopy and the glutamate content was determined by high-performance liquid chromatography.The results of behavior tests showed that modified constraint-induced movement therapy promoted motor and sensory functional recovery in the middle cerebral artery-occluded rats,but had no effect on cognitive function.The modified constraint-induced movement therapy upregulated the expression of glutamate ionotropic receptor AMPA type subunit 3(Gria3)in the hippocampus and downregulated the expression of the beta3-adrenergic receptor gene Adrb3 and arginine vasopressin receptor 1 A,Avprla in the middle cerebral artery-occluded rats.In the ipsilateral hippocampus,only Adra2 a was downregulated,and there was no significant change in Gria3.Transmission electron microscopy revealed a denser distribution the more distribution of postsynaptic glutamate receptor 2/3,which is an a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor,within 240 nm of the postsynaptic density in the contralateral cornu ammonis 3 region.The size and distribution of the synaptic vesicles within 100 nm of the presynaptic active zone were unchanged.Western blot analysis showed that modified constraint-induced movement therapy also increased the expression of glutamate receptor 2/3 and brain-derived neurotrophic factor in the hippocampus of rats with middle cerebral artery occlusion,but had no effect on Synapsin I levels.Besides,we also found modified constraint-induced movement therapy effectively reduced glutamate content in the contralateral hippocampus.This study demonstrated that modified constraint-induced movement therapy is an effective rehabilitation therapy in middle cerebral artery-occluded rats,and suggests that these positive effects occur via the upregulation of the postsynaptic membrane a-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor expression.This study was approved by the Institutional Animal Care and Use Committee of Fudan University,China(approval No.201802173 S)on March 3,2018.

Neuroprotective effects of autophagy inhibition on hippocampal glutamate receptor subunits after hypoxia-ischemia-induced brain damage in newborn rats

Autophagy has been suggested to participate in the pathology of hypoxic-ischemic brain damage（HIBD）.However,its regulatory role in HIBD remains unclear and was thus examined here using a rat model.To induce HIBD,the left common carotid artery was ligated in neonatal rats,and the rats were subjected to hypoxia for 2 hours.Some of these rats were intraperitoneally pretreated with the autophagy inhibitor 3-methyladenine（10 m M in 10 μL） or the autophagy stimulator rapamycin（1 g/kg） 1 hour before artery ligation.Our findings demonstrated that hypoxia-ischemia-induced hippocampal injury in neonatal rats was accompanied by increased expression levels of the autophagy-related proteins light chain 3 and Beclin-1 as well as of the AMPA receptor subunit GluR 1,but by reduced expression of GluR 2.Pretreatment with the autophagy inhibitor 3-methyladenine blocked hypoxia-ischemia-induced hippocampal injury,whereas pretreatment with the autophagy stimulator rapamycin significantly augmented hippocampal injury.Additionally,3-methyladenine pretreatment blocked the hypoxia-ischemia-induced upregulation of Glu R1 and downregulation of GluR2 in the hippocampus.By contrast,rapamycin further elevated hippocampal Glu R1 levels and exacerbated decreased GluR2 expression levels in neonates with HIBD.Our results indicate that autophagy inhibition favors the prevention of HIBD in neonatal rats,at least in part,through normalizing Glu R1 and GluR2 expression.

Synthesis, Characterization and Thermal Properties of Energetic Compounds Derived from 3-Am i no-4-（tetrazo I-5-yl）fu razan

Five energetic compounds, 3,3-bis（tetrazol-5-yl）-4,4-azofurazan （DTZAF）, 3-nitro-4-（tetrazol-5-yl）furazan （NTZF）, hydrazinium 3-amino-4-（tetrazol-5-yl）furazan （HATZF）, triaminoguanidinium 3-amino-4-（tetrazol- 5-yl）furazan （TAGATZF） and guanylureaium 3-amino-4-（tetrazol-5-yl）furazan （MATZF）, were prepared using 3-amino-4-（tetrazol-5-yl）furazan （ATZF） as starting material and their structures were characterized by FT-IR, IH NMR, 13C NMR and elemental analysis. The properties of NTZF were estimated： density is 1.67 g/cm3, enthalpy of formation ＋415.41 kJ/mol and detonation velocity 8257.83 m/s. The main thermal properties of four compounds, DTZAF, HATZF, TAGATZF and MATZF, were analyzed by TG and DSC techniques and the results showed that their melting points are 251.9, 159.7, 205.4 and 211.4 ℃, respectively, and their first decomposition temperatures are 256.7, 258.6, 231.7 and 268.6℃, respectively. The fact that their decomposition temperatures were over 230 ℃ showed that they exhibit better thermal stability.