English

• 

  1   INTRODUCTION

  Heterocyclic compounds, especially the nitrogen containing compounds, play an important role in modern pesticide industry^{[1, 2]} with high activity and good selectivity^[3]. Benzofurans, belonging to the bicyclic ring system, are very well attracted for chemistry and biology in recent years. The compounds possessing benzofuran nucleus often have useful pharmacological and agrochemical properties, such as antifungal, antimicrobial, insecticide, antiarrythmic, and antimigraine^{[4, 5]}.

  The molecules with furan ring are widely used in pharmaceutical and agrochemical industries for their various activities, such as antifungal, herbicidal, insecticidal, potential prophylactic antitumor and so on^[6-8].

  Pyrazole, a heterocyclic compound containing two N atoms, is now widely used in every walk of life^[9]. Pyrazole and their derivatives are well known as an important class of compounds because of their various properties. For example, compounds containing the pyrazole scaffold have herbicidal activities^[10], insecticidal activities^[11], anti-microbial activity^{[12, 13]}, anti-TMV activities^[14], anti-inflammatory^[15], and so on.

  Transketolase plays an important role in plant photosynthesis calvin cycle and it can be developed as a new herbicide target^[16]. We previously used the transketolase as target and computer-aided drug screening technology to obtain some amide compounds, and the bioassay results showed that some amide compounds containing pyrazole and benzofuran rings exhibited good biological activity. In order to find novel pyrazole- and benzofuran-based pesticide leads, the title compound was designed and synthesized according to the routine described in Scheme 1, and its crystal structure and biological activities were determined and evaluated.

  Figure Scheme1.  Synthetic route of the title compound

  图选项

  下载全尺寸图像

  下载幻灯片

  2   EXPERIMENTAL

  All reagents and solvents for synthesis and analyses were of analytical grade and used without further purification except dichloromethane. Column chromatography purification was carried out by using silica gel (200～300). The melting point was measured on an XT-4A apparatus and uncorrected. ¹H-NMR and ¹³C-NMR spectra were measured at 400 MHz and 100 MHz respectively using a Bruker AV-400 spectrometer with deutero-chloroform (CDCl₃) as the solvent and tetramethylsilane (TMS) as the internal standard. The single-crystal structure was determined on a Rigaku Saturn 724 CCD diffractometer. The high resolution mass spectra were recorded on an Agilent 6520-QTOF LC/MS having ESI source in a positive mode.

  2.1   Synthesis

  2.2   Crystal data and structure determination

  The crystal of the title compound (5) was cultivated from ethyl acetate and petroleum ether (v/v = 1:10), and the colorless prism with dimensions of 0.20mm× 0.18mm × 0.12mm was selected for X-ray diffraction analysis. All measurements were made on a Rigaku Saturn 724 CCD diffractometer MoKα radiation (λ = 0.71073 Å). The data were collected at 113(2) K and the crystal is of monoclinic system, space group P2₁/c, with a = 20.6205(18), b = 5.2930(5), c = 18.9282(17) Å, β = 94.089(2)°, V = 2060.6(3) ų, Z = 4, density (calculated) = 1.384 g/cm3, and linear absorption coefficient 0.095 mm^-1. In the range of 3.03≤θ≤27.51°, a total of 19714 reflections were collected with 4714 unique ones (R_int = 0.0203), and completeness of data (to theta = 27.51°) of 99.5%. The data were collected and processed using Crystal Clear (Rigaku). An empirical absorption correction was applied using Crystal Clear (Rigaku). The structure was solved by direct methods with SHELXS-97 program^[18]. Refinements were done by full-matrix least-squares on F2 with SHELXL-97^[19]. All non-hydrogen atoms were refined anisotropically by full-matrix least-squares to give the final R = 0.0345, wR = 0.0930 (w = 1/[σ²(F_o ²) + (0.0515P)² + 0.6568P], where P = (F_o ² + 2F_c ²)/3) with (Δ/σ)_max = 0.002 and S = 1.046 by using the SHELXL program. The hydrogen atoms were located from a difference Fourier map and refined isotropically. The corrections for absorption were multi-scan, T_min = 0.9812 and T_max = 0.9887.

  2.3   Biological screening

  2.1.5   Synthesis of the title compound 2-((2, 2-dimethyl-2, 3-dihydrobenzofuran- 7-yl)oxy)- N-(3-(furan-2-yl)-1-phenyl- ¹H-pyrazol-5-yl) acetamide (5)

  A solution of 3-(furan-2-yl)-1-phenyl-H-pyrazol- 5-amine (0.214 g, 0.95 mmol) and Et₃N (0.116 g, 1.14 mmol) in anhydrous DCM (10 mL) was stirred and cooled in ice/salt mixture. After the temperature was sub-zero, a solution of 2-((2, 2-dimethyl-2, 3- dihydrobenzofuran-7-yl) oxy) acetyl chloride (0.275 g, 1.14 mmol) in DCM (10 mL) was added in a dropwise manner. The reaction mixture was then stirred at room temperature, and the progress was controlled by TLC. After completion of the reaction, the mixture was washed successively with aqueous hydrochloric acid solution (3.6%, 30 mL), saturated sodium bicarbonate solution (30 mL) and brine (30 mL), and the organic layer was dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The crude product was purified by column chromatography on silica using ethyl acetate and petroleum ether (v/v = 1:3) to provide 0.31 g of the yellow solid with yield 75.98%. m.p.: 107～109 ℃. ¹H NMR (400 MHz, CDCl₃) δ 8.82 (s, ¹H, NH), 7.49 (d, J = 7.2 Hz, 3H, Ph-H), 7.44 (s, 3H, Ph-H), 7.09 (s, ¹H, Pyrazol-H), 6.90 (d, J = 7.3 Hz, 1H, Furan-H), 6.78 (dd, J = 7.6, 5.8 Hz, 2H, Ph-H), 6.67 (d, J = 8.0 Hz, 1H, Furan-H), 6.51 (d, J = 1.7 Hz, ¹H, Furan-H), 4.73 (s, 2H, -OCH₂-), 3.04 (s, 2H, CH₂), 1.43 (s, 6H, 2×CH₃). ¹³C NMR (100 MHz, CDCl₃): δ = 165.77, 148.34, 147.67, 144.48, 142.22, 141.68, 137.51, 135.56, 129.80, 129.47, 128.38, 124.57, 120.73, 119.90, 114.59, 111.31, 106.75, 95.44, 88.16, 69.20, 43.07, 28.18. H RMS(ESI)[M+H]⁺ calcd. for C₂₅H₂₃N₃O4 : 430.1767. Found: 430.1760.

  2.1.2   Synthesis of 3-(furan-2-yl)-1- phenyl-H-pyrazol-5-amine (2)

  2-Furoylacetonitrile (2.00 g, 14.8 mmol) was added in a 25 mL round-bottomed flask, followed by adding phenylhydrazine (1.60 g, 14.8 mmol). The reaction was then heated to 130 ℃ and the progress was detected by TLC. After completion of the reaction, the crude product was purified by column chromatography on silica gel eluting with dichloromethane to afford the pure product. Yield 90.09%. m.p. 119～121 ℃. ¹H NMR (400 MHz, CDCl₃) δ 7.64 (d, J = 7.8 Hz, 2H, Ph-H), 7.52 (t, J = 7.8 Hz, 2H, Ph-H), 7.47 (d, J = 0.9 Hz, ¹H, Furan-H), 7.40 (t, J = 7.4 Hz, ¹H, Ph-H), 6.71 (d, J = 3.3 Hz, ¹H, Furan-H), 6.48 (dd, J = 3.3, 1.8 Hz, ¹H, Furan-H), 5.93 (s, ¹H, Pyrazol-H), 3.90 (s, 2H, NH₂).

  2.1.4   Synthesis of 2-((2, 2-dimethyl-2, 3-dihydrobenzofuran- 7-yl)oxy) acetyl chloride (4)

  A mixture of 2-((2, 2-dimethyl-2, 3-dihydrobenzofuran- 7-yl) oxy) acetic acid (0.5 g, 2.25 mmol), SOCl₂ (1.81 g, 15.8 mmol), and a catalytic amount of DMF (0.1 mL) in anhydrous toluene (20 mL) was stirred at 70 ℃ for 5 h. Then, toluene and excess SOCl₂ were removed in vacuum, and finally the residue was dried in vacuum to give the desired product which could be directly used for the next process without purification.

  2.1.3   Synthesis of 2-((2, 2-dimethyl-2, 3- dihydrobenzofuran- 7-yl)oxy) acetic acid (3)

  A mixture of benzofuranol (3.28 g, 19.98 mmol) and NaOH (0.96 g, 2.40 mmol) in anhydrous toluene was stirred for 3 h at 105 ℃, followed by adding ClCH₂COONa (3.48 g, 29.97 mmol). The reaction mixture was then stirred at the same temperature and the progress was detected by TLC. After the completion of the reaction, the mixture was cooled to room temperature and filtered. The filtrate was concentrated in vacuo to afford the solid material. The solid material was dissolved in 100 mL of water and cooling ice/salt mixture. Then HCl 3.6% was added until pH = 1～2. The precipitate was filtered and washed with water until neutral, then recrystallized from water/ethanol = 5:1 (v/v) to give the desired product.

  2.1.1   Synthesis of 2-furoylacetonitrile (1)

  A mixture of methyl furoate (12.61 g, 100 mmol) and CH₃CN (12.5 mL, 300 mmol) was dissolved in 100 mL of toluene, then NaH (60%, 12 g, 300 mmol) was added and the reaction mixture was stirred for 24 h at reflux temperature. After cooling to room temperature, it was filtered and washed with 30 mL of CH₂Cl₂. The solid material was dissolved in 100 mL of water and cooling ice/salt mixture. Then HCl 15% was added until pH = 2~3 by keeping the temperature below 5 ℃. The precipitate was filtered and washed with water until neutral. The crude product was purified by column chromatography on silica gel with ethyl acetate and petroleum ether (v/v = 1:2) as eluent to afford the pure product^[17].

  2.3.1   Herbicidal bioassay

  The effect of the target compound (5) on inhibiting the growth of D. sanguinalis and A. retroflexus was determined based on the foliar spray treatment method^[20] and the small cup method. A stock solution of compound 5 was prepared at 1000 μg/mL using sterilized water containing 2 drops of N, Ndimethylformamide (DMF) as solvent. Subsequently, the stock solution was sprayed on the leaves of D. sanguinalis and A. retroflexus, and each treatment was repeated by three times. The symptoms were then monitored at 72 h post-treatment and compared with those of the untreated control. The grading standard^[21] about the inhibitional effect of foliar treatment method is shown in Table 3. The small cup method was as follows. 1 mL of the stock solution was added in a 40 mL of beaker with a layer of glass beads and double filter paper on the bottom, then 10 seeds of D. sanguinalis and A. retroflexus were put on the filter paper, respectively. Each treatment was repeated by three times and the inhibition rate of the target compound (5) on the root and stem of D. sanguinalis and A. retroflexus were measured at 72 h post-treatment.

  2.3.2   Fungicidal bioassay

  The effect of the target compound (5) on inhibiting the growth of fungi was assessed using the fungi growth inhibition method^[22]. Representative fungi used in this study included Alternaria solani (AS), Botrytis cinerea (BC), Cercospora arachidicola (CA), Gibberella zeae (GZ), Phytophthora infestans (Mont) de Bary (PI), Physalospora piricola (PP), Pellicularia sasakii (PS), Sclerotinia sclerotiorum (SS), and Rhizoctonia cerealis (RC).

  3   RESULTS AND DISCUSSION

  3.1   Synthesis and spectra analysis

  The synthesis procedure for the target compound is shown in Scheme 1. The intermediate 2-((2, 2- dimethyl-2, 3-dihydrobenzofuran-7-yl) oxy) acetic acid (3) was synthesized by the reaction of benzofuranol with ClCH₂COONa and NaOH instead of the hypertoxic ClCH₂COOH. The temperature was a key factor in the synthesis procedure of the key intermediate 3-(furan-2-yl)-1-phenyl-H-pyrazol- 5-amine (2). We first used EtOH as solvent, and the cycling reaction of 2-furoylacetonitrile with phenylhydrazine was progressed at the reflux temperature. By-product was formed and the yield of the desired product was low. When 2-furoylacetonitrile was allowed to react with phenylhydrazine in neat condition at 130 ℃, the desired product was successfully generated in a high yield without any by-product.

  The structure of the target compound was well characterized by ¹H NMR, ¹³C NMR and H RMS. ¹H NMR displayed a characteristic singlet at δ 8.82 ppm which was assigned to proton of NH group. The ¹³C NMR also showed distinctive peak at δ 165.77 ppm corresponding to carbonyl carbon. Further structure confirmation was provided by ESI-mass spectrum which showed the molecular ion peak as the base peak at m/z 430.1760 [M+H]⁺. The structure of the target compound was further authenticated by single-crystal X-ray diffraction.

  3.2   Crystal structure description

  The molecular structure of the title compound is shown in Fig. 1 and the packing diagram in Fig. 2. The selected bond lengths, bond angles and torsion angles are listed in Table 1, and the parameters of intramolecular bonds are given in Table 2.

  Figure 1.  Molecular structure of the title compound shown at 30%thermal probability

  图选项

  下载全尺寸图像

  下载幻灯片

  Figure 2.  Crystal packing of the title compound

  图选项

  下载全尺寸图像

  下载幻灯片

  Table 1.  Selected Bond Lengths (Å), Bond Angles (°) and Torsion Angles (°) for the Title Compound

  表选项

  导出Excel

  下载全尺寸表图像

  Bond Dist. Bond Dist. Bond Dist. O(1)-C(1) 1.3700(12) N(1)-C(12) 1.3590(13) C(1)-C(6) 1.3857(15) Angle (°) Angle (°) Angle (°) C(12)-N(1)-C(13) 123.68(9) N(3)-N(2)-C(13) 111.00(8) C(15)-N(3)-N(2) 104.58(8) Torsion angle (°) Torsion angle (°) Torsion angle (°) C(11)-O(2)-C(2)-C(1) 179.66(9) C(2)-O(2)-C(11)-C(12) 177.30(8) N(3)-C(15)-C(16)-C(17) -15.90(18) C(14)-C(15)-C(16)-O(4) -18.02(15) C(13)-N(2)-C(20)-C(21) -37.68(16) N(3)-N(2)-C(20)-C(25) -27.51(13)

  O(1)-C(8)	1.4931(12)	N(1)-C(13)	1.3942(13)	C(7)-C(8)	1.5409(15)
  O(2)-C(2)	1.3786(12)	N(2)-N(3)	1.3706(12)	C(13)-C(14)	1.3732(14)
  O(2)-C(11)	1.4244(12)	N(2)-C(13)	1.3722(13)	C(16)-C(17)	1.3542(14)
  O(3)-C(12)	1.2174(13)	N(2)-C(20)	1.4264(12)	C(14)-C(15)	1.4130(14)
  O(4)-C(19)	1.3704(13)	N(3)-C(15)	1.3329(13)	C(17)-C(18)	1.4289(15)
  C(12)-N(1)-H(1)	114.7(10)	N(3)-N(2)-C(20)	118.20(8)	C(6)-C(5)-C(4)	118.46(10)
  C(13)-N(1)-H(1)	121.5(10)	C(13)-N(2)-C(20)	130.17(9)	C(19)-O(4)-C(16)	105.97(8)

  Table 1.  Selected Bond Lengths (Å), Bond Angles (°) and Torsion Angles (°) for the Title Compound
  Table 2.  Intramolecular Hydrogen Bonds of the Title Compound

  表选项

  导出Excel

  下载全尺寸表图像

  D-H-A	d(D-H)	d(H-A)	d(D-A)	Z(DHA)
  N(1)-H(1)…O(2)	0.885(9)	2.133(14)	2.6149(12)	113.5(11)

  Table 2.  Intramolecular Hydrogen Bonds of the Title Compound
  Table 3.  Grading Standard about the Inbibitional Effect through Foliar Treatment

  表选项

  导出Excel

  下载全尺寸表图像

  Degree	Inhibitionrate of growth (%)
  0	The same as control
  1	<25
  2	25-50
  3	50-75
  4	75-95
  5	>95

  Table 3.  Grading Standard about the Inbibitional Effect through Foliar Treatment

  As shown in Table 1, the average bond lengths and bond angles within the heterocyclic and benzene rings agree well with the normal ranges^[23-26]. Owing to the π-π conjugation between pyrazole and phenyl rings in adjacent dimmers, the bond length of N(2)-C(20) (1.4264(12) Å) is slightly shorter than the normal C-N (1.47 Å)^[27]. The sum of C(12)- N(1)-C(13), C(12)-N(1)-H(1) and C(13)-N(1)-H(1) angles is 359.88°, indicating the sp² hybridization state of N(1) atom. In the title compound, the furan and pyrazole rings are nonplanar with the torsion angles of C(14)-C(15)-C(16)-O(4) and N(3)- C(15)-C(16)-C(17) to be -18.02(15) and -15.90(18), respectively. The torsion angles of C(13)-N(2)- C(20)-C(21) and N(3)-N(2)-C(20)-C(25) are -37.68(16) and -27.51(13)°, which means that the pyrazole rings and benzene ring (C(20)～C(25)) are nonplanar. The torsion angles of C(11)-O(2)- C(2)-C(1) and C(2)-O(2)-C(11)-C(12) are 179.66(9) and 177.30(8)°, respectively, so the benzofurans ring and carbonyl part at C(11)-C(12)-O(3) are similarly planar. X-ray single-crystal diffraction analysis reveals that the title compound presents intramolecular hydrogen bonds of N(1)-H(1)···O(2) (N(1)-O(2) = 2.6149 Å, ∠N-H···O = 113.5°). There also exist intermolecular weak interactions at O(3)···H(4) (Fig. 2). In the packing structure, clear intermolecular π-π interactions are observed between the furan, pyrazole and phenyl rings in adjacent dimers. The intramolecular hydrogen bonds, intermolecular weak interactions and π-π interactions connect the molecules into one-dimensional tapes.

  4   BIOLOGICAL ACTIVITY

  The herbicidal activity of the target compound (5) was determined. The results of foliar treatment showed that the growth of control weeds treated with compound 5 was slightly inhibited. The levels of the inhibitional effect on D. sanguinalis and A. retroflexus are 2 and 1 degree, respectively. The results of the small cup method showed that the inhibition rate against D. sanguinalis reached 63.05% (root) and 57.94% (stalk), and A. retroflexus 69.83% (root) and 35.82% (stalk).

  The inhibition effects of the target compound (5) against nine typical fungi were tested. The results showed that the target compound presented good to moderate fungicidal activity against AS, CA, BC and SS with the inhibition rates of 47.06%, 53.85%, 70.00% and 84.62%, respectively. While, the target compound presented a little fungicidal activity against PI, GZ, PP, RC and PS with the inhibition rates of 18.18%, 29.63%, 12.50%, 17.39% and 10.87%, respectively. These results indicated that the target compound showed a potential fungicidal activity with relatively broad-spectrum.

  5   CONCLUSION

  The novel pyrazole- and benzofuran-based target compound was designed and synthesized. The structure of the target compound was characterized by ¹H NMR, ¹³C NMR, H RMS and single-crystal X-ray diffraction. The H RMS data are in agreement with its molecular weight and the data of singlecrystal X-ray diffraction further confirmed the structure of the target compound. The bioassays showed that the target compound exhibited moderate herbicidal activity against the two target weeds and good fungicidal activity to one or more selected fungi. This work will lay a foundation for the design and synthesis of new compounds with high biological activity.

• 1. [1]

     Lamberth C.. Heterocyclic chemistry in crop protection[J]. Pest. Manag. Sci., 2013, 69:  1106-1114. doi: 10.1002/ps.2013.69.issue-10

  2. [2]

     He H. W., Peng H., Wang T., Wang C. B., Yuan J. L., Chen T., He J. B., Tan X. S.. α-(Substituted-phenoxyacetoxy)-α-heterocyclylmethylphosphonates: Synthesis, herbicidal activity, inhibition on pyruvate dehydrogenase complex (PDHc), and application as postemergent herbicide against broadleaf weeds[J]. Agric. Food Chem., 2013, 61:  2479-2488. doi: 10.1021/jf305153h

  3. [3]

     Plem S. C., Müller D. M., Murguía M. C.. Key intermediates: a simple and highly selective synthesis of 5-amino-1-aryl-1H-pyrazole-4-carbonitriles for applications in the crop protection[J]. Adv. Chem. Eng. Sci., 2015, 5:  239-61. doi: 10.4236/aces.2015.53025

  4. [4]

     Mohamed, H. A.; Abdellatif, E.; Abdelwahab, B. F.; Awad, G. E. Novel antimicrobial agents: fluorinated 2-(3-(benzofuran-2-yl)pyrazol-1-yl)thiazoles. Int. J. Med. Chem. 2013, 1-6.

  5. [5]

     Patil V., Asrondkar A., Pande S., Bobade A. S., Chowdhary A. S.. Synthesis of 5-aryl-3-(5-bromo-3-benzofuran-2-yl)-1-pyrazole as antimicrobial agent[J]. J. Pharm. Bio. Sci., 2013, 8:  04-08.

  6. [6]

     Zhu, H. L.; Shi, J.; Huang, Z. Q.; Lv, L. J.; Duan, J. W. Structures, spectroscopic analysis, herbicidal activities and enamine-aminone tautomerism of new b-diketone derivatives modified with glycylglycine methyl ester. J. Mol. Struct. 2015, 1089, 170-177.

  7. [7]

     Agnieszka M., Jaroslaw L., Piotr R., Robert B.. Phytotoxicity of new furan-derived aminophosphonic acids, n-aryl furaldimines and 5-nitrofuraldimine[J]. J. Agric. Food Chem., 2013, 61:  7673-7678. doi: 10.1021/jf402401z

  8. [8]

     Wang B., Shi Y., Zhan Y., Zhang L., Zhang Y., Wang L., Zhang X., Li Y., Li Z., Li B.. Synthesis and biological activity of novel furan/thiophene and piperazine-containing (bis)1, 2, 4-triazole mannich bases[J]. Chin. J. Chem., 2015, 33:  1124-1134. doi: 10.1002/cjoc.201500436

  9. [9]

     Balsevena H., Isgörm M. M., Mertam S., Alım Z., Beydemir S., Ok S., Kasımog˘ulları R.. Facile synthesis and characterization of novel pyrazole-sulfonamides and their inhibition effects on human carbonic anhydrase isoenzymes[J]. Bioorg. Med. Chem., 2013, 21:  21-27. doi: 10.1016/j.bmc.2012.11.012

  10. [10]

      Masami O., Hiroshi M., Eizo M.. Plastid damage in photosynthetic cells of mizugayatsuri (Cyperus serotinus) leaves treated with a pyrazole herbicide[J]. Plant. Prod. Sci., 2001, 4:  291-303. doi: 10.1626/pps.4.291

  11. [11]

      Ali A., Nayar J. K., Gu W. D.. Toxicity of a phenyl pyrazole insecticide, fipronil, to mosquito and chironomid midge larvae in the laboratory[J]. J. Am. Mosquito. Contr., 1998, 14:  216-218.

  12. [12]

      Acharya A. P., Kamble R. D., Hese S. V., Kadam S. N., Gacche R. N., Dawane B. S.. Eco-friendly synthesis of novel indeno-pyrazole derivatives and their in-vitro antimicrobial screening[J]. Org. Commun., 2014, 7:  68-76.

  13. [13]

      Yu P., Li X., Hu J., Xu Y. H.. Synthesis, bioactivity and crystal structure analysis of 2-(benzo[J]. Chin. J. Struct. Chem., 2014, 33:  1375-1382.

  14. [14]

      Hong Y. P., Shangguan X. C., Iqbai Z., Yin X. L.. Synthesis, X-ray crystallographic analysis and bioactivities of α-aminophosphonates featuring pyrazole and fluorine moieties[J]. Chin. J. Struct. Chem., 2014, 33:  1673-1682.

  15. [15]

      Li Y. R., Li C., Liu J. C., Guo M., Zhang T. Y., Sun L. P., Zheng C. J., Piao H. R.. Synthesis and biological evaluation of 1, 3-diaryl pyrazole derivatives as potential antibacterial and anti-inflammatory agents[J]. Bioorg. Med. Chem. Lett., 2015, 25:  5052-5057. doi: 10.1016/j.bmcl.2015.10.028

  16. [16]

      Henkes S., Sonnewald U., Badur R., Flachmann R., Stitt M.. A small decrease of plastid transketolase activity in antisense tobacco transformants has dramatic effects on photosynthesis and phenylpropanoid metabolism[J]. The Plant Cell, 2001, 13:  535-551. doi: 10.1105/tpc.13.3.535

  17. [17]

      Ma L. C., Yuan L. W., Xu C. Z., Li G. W., Tao M. L., Zhang W. Q.. An efficient synthesis of 2-aminothiophenes via the gewald reaction catalyzed by an N-methylpiperazine functionalized polyacrylonitrile fiber[J]. Chem. Inform., 2013, 45:  45-52.

  18. [18]

      Sheldrick, G. M. SHELXS-97, Program for Solution of Crystal Structures. University of Gottingen, Germany 1997.

  19. [19]

      Sheldrick, G. M. SHELXL-97, Program for Crystal Structure Refinement. University of Gottingen, Germany 1997.

  20. [20]

      Zhang J. L., Zhang L. H., Liu Y. C., Ma J., Li C., Dong J. G.. The herbicidal activity of mutant isolates from Botrytis cinerea[J]. Agr. Sci. China, 2006, 5:  622-628. doi: 10.1016/S1671-2927(06)60102-8

  21. [21]

      Xu J., Xu W. C., Kang Z. H., Liu B. F., Zhang J. L.. Isolation and structural indentification of herbicidal toxin fractions produced by pythium aphanidermatum[J]. Agr. Sci. China, 2009, 42:  1994-2001.

  22. [22]

      Li F. Y., Zhu Y. J., Fan Z. J., Xu J. H., Guo X. F., Zong G. N., Song H. B., Chen L., Song Y. Q., Qian X. L., Ma L. Y., Wang J. R.. Synthesis, crystal structure and biological activity of 2-(1-(3-bromo-1-(3-chloropyridin-2-yl)-1H-pyrazole-5- carbonyl)piperidin-4-yl)-N-isopropyl-1, 3-thiazole- 4-carboxamide[J]. Chin. J. Struct. Chem., 2015, 34:  659-666.

  23. [23]

      Yan L., Xue S. J.. Crystal structure and biological activities of N-(5-(4-chloro-2-(trifluoromethyl) phenyl) furan-2-carbonyl)-N?-(4, 6-dimethylpyrimidin-2-yl) thiourea[J]. Chin. J. Struct. Chem., 2008, 27:  543-546.

  24. [24]

      Wen H. L., Kang J. J., Dai B., Deng R. H., Hu H. W.. Syntheses, crystal structures and antibacterial activities of 5-chloro-3-methyl- 1-phenyl-1H-pyrazole-4-carboxylic acid and its copper(II) compound[J]. Chin. J. Struct. Chem., 2015, 34:  33-40.

  25. [25]

      Zhou B. H., Hua Y. T., Xu B. M., Ma L., Hu J. W., Liu Z. J.. Syntheses, crystal structures and antifungal activities of two compounds containing pyrazole and pyrethroid units[J]. Chin. J. Struct. Chem., 2015, 34:  1231-1237.

  26. [26]

      Jerzy K., Elzbieta H., Irena W.. Synthesis and structural characterization of aminoalkanol derivatives of 2, 3-dihydro-2, 2-dimethyl-7-benzofuranol with an expected?-adrenolytic and/or anxiolytic activity[J]. Z. Naturforsch., 2002, 57:  285-294.

  27. [27]

      Chen, X. M.; Cai, J. W. Single-crystal Structural Analysis Principles and Practices. Science Press: Beijing 2003, 114-115.

• 

  Scheme1  Synthetic route of the title compound

  下载: 全尺寸图片 幻灯片
  

  Figure 1  Molecular structure of the title compound shown at 30%thermal probability

  下载: 全尺寸图片 幻灯片
  

  Figure 2  Crystal packing of the title compound

  下载: 全尺寸图片 幻灯片

  Table 1.  Selected Bond Lengths (Å), Bond Angles (°) and Torsion Angles (°) for the Title Compound

  Bond Dist. Bond Dist. Bond Dist. O(1)-C(1) 1.3700(12) N(1)-C(12) 1.3590(13) C(1)-C(6) 1.3857(15) Angle (°) Angle (°) Angle (°) C(12)-N(1)-C(13) 123.68(9) N(3)-N(2)-C(13) 111.00(8) C(15)-N(3)-N(2) 104.58(8) Torsion angle (°) Torsion angle (°) Torsion angle (°) C(11)-O(2)-C(2)-C(1) 179.66(9) C(2)-O(2)-C(11)-C(12) 177.30(8) N(3)-C(15)-C(16)-C(17) -15.90(18) C(14)-C(15)-C(16)-O(4) -18.02(15) C(13)-N(2)-C(20)-C(21) -37.68(16) N(3)-N(2)-C(20)-C(25) -27.51(13)

  O(1)-C(8)	1.4931(12)	N(1)-C(13)	1.3942(13)	C(7)-C(8)	1.5409(15)
  O(2)-C(2)	1.3786(12)	N(2)-N(3)	1.3706(12)	C(13)-C(14)	1.3732(14)
  O(2)-C(11)	1.4244(12)	N(2)-C(13)	1.3722(13)	C(16)-C(17)	1.3542(14)
  O(3)-C(12)	1.2174(13)	N(2)-C(20)	1.4264(12)	C(14)-C(15)	1.4130(14)
  O(4)-C(19)	1.3704(13)	N(3)-C(15)	1.3329(13)	C(17)-C(18)	1.4289(15)
  C(12)-N(1)-H(1)	114.7(10)	N(3)-N(2)-C(20)	118.20(8)	C(6)-C(5)-C(4)	118.46(10)
  C(13)-N(1)-H(1)	121.5(10)	C(13)-N(2)-C(20)	130.17(9)	C(19)-O(4)-C(16)	105.97(8)

  下载: 导出CSV

  Table 2.  Intramolecular Hydrogen Bonds of the Title Compound

  D-H-A	d(D-H)	d(H-A)	d(D-A)	Z(DHA)
  N(1)-H(1)…O(2)	0.885(9)	2.133(14)	2.6149(12)	113.5(11)

  下载: 导出CSV

  Table 3.  Grading Standard about the Inbibitional Effect through Foliar Treatment

  Degree	Inhibitionrate of growth (%)
  0	The same as control
  1	<25
  2	25-50
  3	50-75
  4	75-95
  5	>95

  下载: 导出CSV
•