Synthesis of plant-based biogenic jarosite nanoparticles using Azadirachta indica and Eucalyptus gunni leaf extracts and its application in Fenton degradation of dicamba

Bio-jarosite,an iron mineral synthesized biologically using bacteria,is a substitute for iron catalysts in the Fenton oxidation of organic pollutants.Iron nanocatalysts have been widely used as Fenton catalysts because they have a larger surface area than ordinary catalysts,are highly recyclable,and can be treated efficiently.This study aimed to explore the catalytic properties of bio-jarosite iron nanoparticles syn-thesized with green methods using two distinct plant species:Azadirachta indica and Eucalyptus gunni.The focus was on the degradation of dicamba via Fenton oxidation.The synthesized nanoparticles exhibited different particle size,shape,surface area,and chemical composition characteristics.Both particles were effective in removing dicamba,with removal efficiencies of 96.8%for A.indica bio-jarosite iron nano-particles(ABFeNPs)and 93.0%for E.gunni bio-jarosite iron nanoparticles(EBFeNPs)within 120 min of treatment.Increasing the catalyst dosage by 0.1 g/L resulted in 7.6%and 43.0%increases in the dicamba removal efficiency for EBFeNPs and ABFeNPs with rate constants of 0.025 min^(-1) and 0.023 min^(-1),respectively,confrming their catalytic roles.Additionally,the high efficiency of both catalysts was demonstrated through five consecutive cycles of linear pseudo-first-order Fenton oxidation reactions.

Simple,Mild and Convenient Synthesis of Two Novel N-Dichloro-acetyl Oxazolidines and their Biological Activities

Two N-dichloroacetyl oxazolidines were synthesized with a simple, mild and convenient method. All the compounds were characterized by IR, HNMR and elemental analysis. The 1 preliminary biological test showed that the compounds protected maize against injury by some herbicides to some extent.

Summarization and Analysis on the Synthesis Schemes of Glufosinate-Ammonium

Glufosinate-ammonium is a highly efficient, non-selective herbicide. The former synthesis schemes of glufosinate-ammonium were introduced and analyzed, the main of which are Arbuzov synthesis method, method under catalyzer and high pressure, targeted method under low temperature, Gabriel synthesis method, Zelinsky-Strecher synthetic method, synthetic method with chiral-synthon, and several special methods such as with enzyme or stereochemistry. Based on the structure and synthesis characteristic of glufosinate-ammonium as well as Arbuzov reaction and Michael reaction, a novel and reasonable scheme, which was named Arbuzov-Michael method, was put forward as the more economical one with simpler raw reagents and less waste.

Synthesis,Crystal Structure and Herbicidal Activity of O,O'-Diethyl-N-[2-(5,7-dimethyl-[1,2,4]triazolo[1,5-a]pyrimidin-2-yloxy)-benzoxyl]-1-amino-benzyl phosphonate

The crystal structure of the title compound （C25H28N5O5P,Mr=509.49） has been determined by single-crystal X-ray diffraction.The crystal is of monoclinic,space group P21/c with a=13.0726（4）,b=13.4513（4）,c=15.103（1）,β=93.650（1）°,V=2650.29（14）3,Z=4,Dc= 1.277 g/cm3,F（000）=1072,μ（MoKα）=0.147 mm-1,the final R=0.0748 and wR=0.1956 for 3186 observed reflections （I 〉 2σ（I））.The fused triazolopyrimidine system ring is coplanar,the dihedral angles between the triazolopyrimidine and C（1）-C（3）-C（5） phenyl,the triazolopyrimidine and C（17）-C（19）-C（21） phenyl,and the two phenyl rings are 66.87,58.79 and 80.11o,respectively.Intramolecular N（5）-H（5A）…O（3） and intermolecular C（2）-H（2）…N（4）,C（18）-H（18）…O（3）,C（19）-H（19）…O（2） and C（24）-H（24C）…N（4） hydrogen bonds together with C-H…π interactions contribute to the stability of the structure and result in a three-dimensional framework.The preliminary bioassay indicates that the title compound exhibits moderate herbicidal activity against dicotyledonous plants （Brassica campestris L） at the concentration of 100 mg/L.

Synthesis and Crystal Structure of N-(1,3,4-Thiadiazol-2-yl)-1-[1-(6-chloropyridin-3-yl)methy]-5-methyl-1H-[1,2,3]triazol-4-carboxamide

The crystal structure of the title compound （C12H10ClN7OS, Mr= 335.78） has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group Pi with a = 8.4093（11）, b = 9.4430（12）, c = 11.1454（14） A, α = 95.508（2）, β = 111.366（2）, γ = 115.259（2）°, V = 711.42（16） A3, Z = 2, Dc = 1.568 g/cm3, F（000） = 344, μ（MoKα） = 0.428 mm-1, the final R = 0.0476 and wR = 0.1243 for 2353 observed reflections （I 〉 2o（/））. The dihedral angles between the pyridine and triazole, thiazole and triazole, and pyridine and thiazole rings are 69.2（1）, 9.2（1） and 72.7（1）°, respectively. Intramolecular C（8）--H（8B）...O（1） and N（5）-H（5A）..-N（4） as well as intermolecular C（5）-H（5）...S（1）, C（3）-H（3）.,.N（6） and N（5）-H（5A）...N（1） hydrogen bonds together with weak C-H...Ir hydrogen-bonding and π-π stacking interactions contribute to the stability of the structure. There is also evidence for significant electron delocalization in the triazolyl system.

Controllable Effect of Structural Modification of Sulfonylurea Herbicides on Soil Degradation

The study of soil degradation behaviors of sulfonylurea herbicides in relation to their different structural attributes is utmost important for us to comprehend the development of new eco-friendly herbicides. It is postulated that the structural modification of the chemical structures could influence their degradation rates in soil. Nine devised structures were synthesized to study their herbicidal activity as well as their soil degradation behaviors respectively. The novel compounds I-3-I-7 were characterized by UV, ^1H NMR and ^13C NMR, MS and EA. Bioassays indicated that most of target compounds displayed superior herbicidal activities in comparison with Chlorsulfuron. Soil degradation results further confirmed our previous assumption that the introduction of electron-donating substituents at 54 position of the benzene ring distinctly increased their degradation rates, among which dimethylamino and diethylamino groups can adjust the degradation rate to a more favorable status.

Synthesis and Herbicidal Activity of Derivatives of Toxin III from Phoma herbarbum

[Objective] In order to improve the herbicidal activity of toxins III（methyl2-methyl-3,5-dinitrobenzoate） from Phoma herbarbum, its structure was optimized by derivatization. [Method] Sixteen novel title compounds were synthesized by nitration and acylation with o-toluic acid as a starting material. Their structures were confirmed by IR and1 H NMR. [Result] The herbicidal activity screening showed that the inhibition rate of J-L-59 against E. crusgalli roots was 93.7% at 100 μg/ml. The fresh weight efficacy of J-L-59 against A. theophrasti and A. retroflexus was 100%at 1 000 g a.i./hm^2 , and the ED50 value for A. retroflexus was 94.06 g a.i./hm^2 .[Conclusion] J-L-59 has higher herbicidal activity.

Synthesis and Crystal Structure of 2-[(4-Methoxy- 6-methylthio-2-pyrimidinyl)aminocarbonyl- aminosulfonyl] Benzoic Acid Methyl Ester

The title compound 2-[(4-methoxy-6-methylthio-2-pyrimidinyl)aminocarbonyl- aminosulfonyl]benzoic acid methyl ester (C15H16N4O6S2, Mr = 412.44) was obtained by the reaction of (4-methoxy-6-methylthio-2-pyrimidinyl)amine with 2-methoxylcarbonylbenzene-sulfonylisocya- nate. The crystal is of monoclinic, space group P21/c with a =11.169(3), b = 9.508(3), c = 17.690(5) ? b = 91.593(5), Z = 4, V = 1877.9(10) 3, Dc = 1.459 g/cm3, F(000) = 856, m(MoKa) = 0.324 mm-1, R = 0.0690 and wR = 0.1368 for 3301 observed reflections (I > 2s(I)). The N(1)H…N(3) and N(2)H…O(4) hydrogen bonds can be observed. In the molecule the phenyl plane(I), pyrimi- din-2-yl-urea bridge plane(Ⅱ) and ester plane(Ⅲ) form three conjugated systems.

Synthesis and Herbicidal Activity of Novel Sulfonylureas Containing Thiadiazol Moiety

Thirteen novel sulfonylureas containing thiadiazole moiety were synthesized in a two-step reaction. Their structures were determined using IR, ^1H NMR, HRFTMS, and elemental analysis. Herbicidal activities of these compounds were determined in the green house bio-assay. The results show that four compounds among them exhibit some activity toward four tested herbs.

Novel Synthesis,Crystal Structure and Herbicidal Activity of(3R,4R)-4,7,7-Trimethyl-6-oxabicyclo[3.2.1]octane-3,4-diol

The title compound, （3R,4R）-4,7,7-trimethyl-6-oxabicyclo[3.2.1]octane-3,4-diol （Cl0HlsO3）, has been synthesized by using one-step catalytic synthetic method from a-pinene and structurally characterized by means of IR, JH-NMR, J3C-NMR, HRMS and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/n with a = 7.277（4）, b = 18.177（11）, c = 7.939（5） A, β = 91.122（8）°, Z = 4, V = 1049.9（11） A, Dc = 1.178 g/cm3, Mr = 186.24, λ（MoKa） = 0.71073 A, μ = 0.09 mm^-1, F（000） = 408, R = 0.051 and wR = 0.144. The title complex molecules contained two hydroxyls and are connected through hydrogen bonds to generate a two-dimensional network. Especially, the preliminary herbicidal activity results show that the title compound exhibits herbicidal activity against rape （Brassica campestris） and barnyard grass （Echinochloa crusgalli）.

Synthesis and Herbicidal Activities of N'-(substituted pyrimidin-2-yl)-N-Substituted Phenoxyacetyl Thiourea Derivatives

Fifteen N'-(substituted pyrimidin-2-y1)-N-substituted phenoxyacetyl thioureas were synthesized and tested for biological activities. All of them are new compounds and their structures were confirmed by IR. IHNMR. MS and elemental analysis. Some of the target compounds showed excellent inhibitory activities against root and stalk of dicotyledon plant (such as radish). and selective on monoctyledon plant (such as rice).

Synthesis, Crystal Structure and Biological Activity of a New 1,2,4-Triazole Derivative

A new 1,2,4-triazole containing cyclopropane moiety was synthesized and characterized by 1H NMR, MS and elemental analyses. The crystal structure of the title compound （C13H14FN3S, Mr= 263.33） has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 12.614（3）, b = 7.0202（14）, c = 15.556（3）A, β = 110.92（3）°, V = 1286.7（4） A3, Z = 4, F（000） = 552, D,. = 1.359 g/cm3,μ = 0.25 mm-1, the final R = 0.0336 and wR = 0.0898 for 2568 observed reflections with 1 〉 2σ（/）. A total of 10093 reflections were collected, of which 3045 were independent （Rint = 0.0268）. The herbicidal activity of the title compound was determined, and this compound displays excellent herbicidal activity against Brassica campestris.

Synthesis,Crystal Structure and Herbicidal Activity of N-(4-Methylbenzyl)-4-(3-fluorophenyl)-4-piperidinol Hydrochloride

A novel compound N-（4-methylbenzyl）-4-（3-fluorophenyl）-4-piperidinol hydrochloride has been synthesized and its structure （C19H23ClFNO, Mr = 335.83） was characterized by elemental analysis, IR, ^1H NMR, MS and single-crystal X-ray diffraction analyses. The crystal belongs to the triclinic system, space group P1 with a = 7.2163（6）, b = 10.7905（9）, c = 12.2651（10） A, α = 109.576（2）,β = 98.407（2）,γ= 95.956（2）°, V= 878.14（13）A3, Z = 2, Dc = 1.270 g/cm^3,μ = 0.231 mm^-1, F（000） = 356, S = 1.100, the final R = 0.0525 and wR = 0.1425 for 3206 unique reflections （Rint = 0.0140） with 2736 observed ones （I 〉 2σ（I））. The piperidine ring exhibits a chair conformation. The dihedral angle made by the methyl- and fluoro-substituted benzene rings is 66.84（7）°. There are some intra- and intermolecular hydrogen bonding interactions among the molecules, which stabilize the whole crystal structure. The preliminary biological activity tests indicate good herbicidal activity for the title compound, in particular against the roots of some tested plants （such as Brassica campestris L. and Echinochloa crusgallis L.）.

Synthesis, Crystal Structure and Herbicidal Activity of Methyl(E)-α-(Methoxyimino)-2-((4-(3-chloro-5-(trifluoromethyl)-pyridine-2-yl)phenoxy)methyl)benzeneacetate

The title compound methyl(E)-α-(methoxyimino)-2-((4-(3-chloro-5-(trifluoromethyl) pyridine-2-yl)phenoxy)methyl)benzeneacetate(C23 H18 ClF3 N2 O4) has been synthesized and structurally characterized by 1 H and 13 C NMR, and HRMS. Its absolute molecular configuration was investigated by X-ray crystallography. The crystal crystallizes in monoclinic system, space group P21/c with a = 15.0928(7), b = 19.6070(10), c = 7.5535(5) ?, β = 98.176(5)°, V = 2212.6(2) ?3, Z =4, Dc = 1.438 g/cm3, F(000) = 984, μ(Mo Kα) = 0.231 mm-1, the final R = 0.0619 and wR = 0.1681 with 4034 observed reflections with I > 2σ(I). The title compound has significant inhibitory rate against broadleaf weeds. They are all 100% under the dose of 37.5 g.a.i/ha, which was better than mesotrione.

Synthesis, Structure and Biological Activities of 2-Methylthio-3-cyano-7-(4-methoxyphenyl)-pyrazolo[1,5-a]pyrimidine

The crystal structure of 2-methylthio-3-cyano-7-（4-methoxyphenyl）-pyrazolo[1,5- a]-pyrimidine （C15H12N4OS, Mr = 296.35） has been determined by single-crystal X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 9.200（3）, b = 15.570（5）, c = 11.125（4） A,β= 114.273（6）°, V= 1452.7（8） A^3, Z= 4, De= 1.355 g/cm^3, μ= 0.227 mm^-1, F（000） = 616, R = 0.0499 and wR = 0.0949 for 2947 unique reflections with 1633 observed ones （I 〉 2σ（I））. The results show that all ring atoms in the pyrazolopyrimidine moiety are almost coplanar with a strong tensile force, which might be an important active site. The preliminary biological test shows that the title compound has moderate herbicidal activities.

Study on Synthesis and Herbicidal Activity of Heterocyclic Compounds Containing P-P Bond

N,N′-diphenylurea reacted with phosphorus trichloride and phenyl dichlorophosphane giving the heterocyclic compounds 1 and 2 with a direct phosphorus-phosphorus bond (P-P bond), respectively. The new compounds were characterized by elementary analysis, NMR and IR spectra. The results of preliminary bioassay showed that these heterocycles possess selective herbicidal activity at 1.5 kg/hm2.

Synthesis and Herbicidal Activity of 1-Phenoxyacetyl-3-arylimidazolidine-2,4-dione Compounds

In order to find new herbicidal compounds, twelve novel 1-phenoxyacetyl-3-arylimidazolidine-2,4-dione compounds were designed and synthesized by substructure combination strategy using 3-arylimidazolidine-2,4-dione as the intermediate. The structures of the target compounds were confirmed by;H NMR and IR. The preliminary bioassay results showed that most of the target compounds had good inhibition against rape and barnyardgrass at the concentration of 100 mg/L. Especially, compound H3 and H5 showed 100% inhibitory activity against rape.

Synthesis and Crystal Structure of Ethyl 2-(6-(1,3-Dioxo-4,5,6,7-tetrahydro-1H-isoindol-2(3H)-yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) Butanoate

The title compound ethyl 2-（6-（1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2（3H）- yl）-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate 3 was synthesized by the reaction of ethyl 2-（6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4（3H）-yl） butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469（2）, b = 16.7715（5）, c = 13.7153（4） A, β= 104.9680（10）°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08（10） ,A3, Z= 4, Dc = 1.376 g/cm3, F（000） = 904, T= 296（2） K, R = 0.0508 and wR = 0.1478.

Synthesis and Herbicidal Activity of 2-Benzoyliminopyrimido[3,2-b]-1 2,4-Thiadiazolines

A series of 2-benzoyliminopyrimido[3,2-b]-1,2,4-thiadiazolines were synthesized and tested for herbicidal effects. All of them are new compounds and their structures were confirmed by (HNMR)-H-1, IR, MS. The preliminary herbicidal tests show that some of the target compounds have potent activity and very good selectivity to rice.

脲嘧啶类除草剂Tiafenacil的合成及除草活性测定

为了探索除草剂Tiafenacil在防治农业杂草方面的应用前景,以3-氨基-4,4,4-三氟丁烯酸乙酯为原料,经6步反应制备得到Tiafenacil,其结构经1H NMR和ESI-MS确证,并对Tiafenacil进行除草活性测定。结果表明:Tiafenacil在苗前浓度为300 g a.i.·hm^(-2)条件下,其对稗草、苘麻的除草活性均优于对照药剂97%莠去津原药;在苗前浓度为75 g a.i.·hm^(-2)条件下,其对稗草、苘麻的除草活性均优于对照药剂97%氟磺胺草醚原药。苗后浓度为37.5、75、150、300 g a.i.·hm^(-2)条件下,其对稗草、金色狗尾草、百日草、苘麻的除草活性均可达100%,明显优于对照药剂97%氟磺胺草醚原药和97%莠去津原药。