Synthesis,Crystal Structure,and Insecticidal Activity of (Z)‐Nitenpyram Derivatives with Optical Activity

Fourteen novel nitenpyram derivatives (Z)‐4‐substituted‐3‐acetyl‐6‐methylamino ?6‐[N‐(6‐chloro‐3‐pyridinylmethyl)‐N‐ethyl]amino‐5‐nitno‐2‐oxa‐5‐hexene 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 4i , 4j , 4k , 4l , 4m , 4n were synthesized, and their structures were confirmed by ¹H NMR, IR, and elemental analysis. The stereostructure of 4h was determined by the single‐crystal X‐ray analysis. The preliminary bioassay tests showed that most of the title compounds exhibited good insecticide activities against Nilaparvata lugens as well as Aphis medicaginis at 500 mg/L, whereas compound 4h afforded the best activity, with 100% mortality against A. medicaginis at 100 mg/L.     

Synthesis and Insecticidal Activities: cis‐Nitenpyram Analogs with 1,4‐Dihydropyridine Scaffold

By means of multicomponent reactions, via Michael addition, nucleophilic addition, using nitenpyram, substituted aromatic aldehydes, and cyanoacetate compounds or propanedinitrile, a new series of cis‐configuration nitenpyram analogs ( 1a‐1k ) were synthesized by introducing the 1,4‐dihydropyridine scaffold pharmacophore, as shown in Scheme 1. The structures of all compounds were confirmed by IR, ¹HNMR, ¹³C NMR, and elemental analysis. The preliminary bioassay showed that most of the target compounds exhibited good mortality against Aphis craccivora at 500 mg/L.     

Synthesis of the (Z) and (E) isomers of 1,2-diaryl-3-methyl-4,5-dioxo-3-pyrrolidinecarboxylic acid esters. Structural assignment by nmr and mass spectroscopy

Reaction of N-benzylideneaniline, 1a , with 3-methyl-2-oxobutanedioic acid diethyl ester, 2a , produced isomeric 3-methyl-4,5-dioxo-1,2-diphenyl-3-pyrrolidinecarboxylic acid ethyl esters, 3a and 3b . The higher melting isomer, 3a , was shown to have the (Z) configuration by nmr spectroscopy. The (Z) and (E) isomers of 3-methyl-4,5-dioxo-1,2-diphenyl-3-pyrrolidinecarboxylic acid methyl esters, 3c and 3d , were prepared from 1a and 3-methyl-2-oxobutanedioic acid dimethyl ester, 2b . The higher melting isomer, 3c , was shown to have the (Z) configuration. Similarly, N-benzylidene-p-toluidine, 1b , reacted with 2a to form (Z) and (E) isomers of 3-methyl-4,5-dioxo-1-(4-methylphenyl)-2-phenyl-3-pyrrolidinecarboxlic acid ethyl esters, 3e and 3f . Assignment of the ¹³C carbonyl carbon nmr chemical shift was made by preparing 2-methyl-3-oxobutanedioic-1-¹³C acid diethyl ester, 4 , and from it the corresponding (Z) and (E) isomers of 3-methyl-4,5-dioxo-1,2-diphenyl-3-pyrrolidinecarboxylic ¹³C acid ester, 5a and 5b . The mass spectra of the (Z) isomers exhibit prominent ions corresponding to the masses of the Schiff bases used to make them, and ions corresponding to the loss of ArNCOCO from the parent ion. The (E) isomers 3b, 3d and 5b exhibit a prominent ion of mass 264; 3f gives mass 278, corresponding to the loss of the carboalkoxy group.     

Synthesis and Fungicidal Activity of (E)‐α‐(Methoxyimino)benzeneacetate Derivatives Containing 1,2,4‐Triazole Schiff Base Side Chain

To find new strobilurin analogs with high activity against resistant pathogens, twelve (E)‐α‐(methoxyimino)benzeneacetate derivatives containing 1,2,4‐triazole Schiff base side chain 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k , 3l were designed and synthesized. Their structures were confirmed by IR, ¹H‐NMR, EIMS, and elemental analyses. Bioassays indicated that most of the target compounds showed moderate to good fungicidal activities against Physalospora piricola Nose and Alternaria solani. For example, compounds 3d , 3e , and 3f possessed 99.5%, 100%, and 95.6% inhibition against Physalospora piricola Nose, whereas compounds 3d , 3f , and 3g exhibited 92%, 91%, and 92% inhibition against Alternaria solani at the concentration of 50 mg/L, respectively.     

Synthesis,Characterization and Crystal Structures of 1,2,4‐Triazole based Schiff‐Bases and their Copper(I) Complexes

The reaction of of 4‐amino‐5‐ethyl‐2H‐1,2,4‐triazole‐3(4H)‐thione (AETT, L ) with furfural in methanol led to the corresponding Schiff‐Base ( L1 ). The reaction of L1 with [Cu(PPh₃)₂]Cl in methanol gave to the neutral compound [( L1 )Cu(PPh₃)₂Cl] ( 1 ). By recrystallization of 1 from CH₃CN the complex [( L1 )Cu(PPh₃)₂Cl]·CH₃CN ( 1a ) was obtained. All compounds were characterized by infrared spectroscopy, elemental analyses as well as by X‐ray diffraction studies. Crystal data for L1 at ?80 °C: space group with a = 788.4(1), b = 830.3(2), c = 928.8(2) pm, α = 84.53(1)°, β = 65.93(1)°, γ = 72.02(1)°, Z = 2, R₁ = 0.0323; for 1 at ?100 °C: space group with a = 1166.3(1), b = 1423.8(2), c = 1489.1(2) pm, α = 62.15(1)°, β = 72.04(1)°, γ = 88.82(1)°, Z = 2, R₁ = 0.0338 and for 1a at ?100 °C: space group P2₁/c with a = 1294.1(1), b = 1019.8(2), c = 3316.9(4) pm, β = 94.73(1)°, Z = 4, R₁ = 0.0435.     

Synthesis,Characterization, and Crystal Structure of the New Schiff‐Bases derived from 1,2,4‐Triazole and the Structure of [(PPh3)2Cu(AMTT)]NO3·EtOH (AMTT = 4‐Amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione)

The reactions of 4‐amino‐5‐methyl‐2H‐1,2,4‐triazole‐3(4H)‐thione (AMTT, L1 ) with 2‐thiophen carbaldehyde, salicylaldehyde and 2‐nitrobenzaldehyde in methanol led to the corresponding Schiff‐bases ( L1a‐c ). The reaction of L1 with [(PPh₃)₂Cu]NO₃ in ethanol gave the ionic complex [(PPh₃)₂Cu(L1)]NO₃·EtOH ( 2 ) All compounds were characterized by infrared spectroscopy, elemental analyses as well as by X‐ray diffraction studies. Crystal data for L1a at 20 °C: space group P2₁/n with a = 439.6(2), b = 2074.0(9), c = 1112.8(4) pm, β = 93.51(3)°, Z = 4, R₁ = 0.0406, L1b at ?80 °C: space group P2₁/n with a = 1268.9(2), b = 739.3(1), c = 1272.5(1) pm, β = 117.97(1)°, Z = 4, R₁ = 0.0361, L1c at ?80 °C: space group P2₁/n with a = 847.8(1), b = 1502.9(2), c = 981.5(2) pm, β = 110.34(1)°, Z = 4, R₁ = 0.0376 and for 2 at ?80 °C: space group with a = 1247.8(1), b = 1270.3(1), c = 1387.5(1) pm, α = 84.32(1)°, β = 84.71(1)°, γ = 63.12(1)°, Z = 2, R₁ = 0.0539.     

Synthesis and Herbicidal Activity of Novel 4‐Acyl‐2,5‐disubstituted‐3‐hydroxypyrazoles and 4‐Arylcarbonyl‐3‐substitutedisoxazol‐5‐ones

Two series of novel 4‐acyl‐2,5‐disubstituted‐3‐hydroxypyrazoles 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h and 4‐arylcarbonyl‐3‐substitutedisoxazol‐5‐ones 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i were synthesized by the Scotton–Baumann reaction of 2,5‐disubstituted‐2,4‐dihydro‐pyrazol‐3‐ones 1 or 3‐substituted‐4H‐isoxazol‐5‐ones 6 and various acyl chlorides, followed by the Fries rearrangement in the presence of calcium hydroxide and calcium oxide as the catalyst. Their structures were confirmed by IR, ¹H NMR, mass spectroscopy, and elemental analyses. ¹H NMR indicated that compounds 3 existed in enol forms and compounds 7 in keto configurations. The results of preliminary bioassays showed that some of the title compounds 3 and 7 exhibited moderate to good herbicidal activities against Brassica campestris L. at the concentration of 100 mg/L. Isoxazole compounds 7 showed better herbicidal activity against B. campestris L. than pyrazole compounds 3 did at the concentration of 100 mg/L. Moreover, most of the isoxazole compounds displayed higher herbicidal activity against B. campestris L. than Echinochloa crus‐galli. However, these compounds showed weak herbicidal activities at the concentration of 10 mg/L.     

Synthesis and Biological Activity of O‐Methyl Methyl 1‐(Substituted Phenoxyacetoxy)‐1‐(thien‐2‐yl)methylphosphinates

A series of novel O‐methyl methyl 1‐(substituted phenoxyacetoxy)‐1‐(thien‐2‐yl)methylphosphinates 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h were synthesized. Their structures were confirmed by IR, ¹H NMR, mass spectroscopy, and elemental analyses. The results of preliminary bioassays show that some of the title compounds exhibit moderate to good herbicidal and fungicidal activities. For example, the title compounds 5c , 5d , and 5g possess 90–100% inhibition against the tested plants at the concentration of 10 mg/L and 100 mg/L, whereas the title compounds 5a , 5b , 5c , and 5h possess 70–94% inhibition against Phyricularia grisea and Sclerotinia sclerotiorum at the concentration of 50 mg/L.     

Synthesis of benzo[b][1,4]thiazepines by the reaction of 3‐aryl‐1‐(3‐coumarinyl)propen‐1‐ones with 2‐aminothiophenol

3‐(2‐Aryl‐2,3‐dihydro‐benzo[b][1,4]thiazepin‐4‐yl)chromen‐2‐ones ( 2a, e, f ) and (Z)‐3‐(2,3‐dihydro‐2‐arylbenzo[b][1,4]thiazepin‐4(5H)‐ylidene)chroman‐2‐ones ( 3a‐f ) have been synthesized by the reaction of 3‐aryl‐1‐(3‐coumarinyl)propen‐1‐ones ( 1a‐f ) with 2‐aminothiophenol in a hot mixture of toluene and acetic acid. Structures of all new compounds and their complete ¹H and ¹³C assignments were achieved applying different one‐ and two‐dimensional nmr experiments in combination with various spectroscopic techniques.     

Synthesis and Biological Activities of Novel 6‐Alkylamino‐11,12‐dihydro‐11‐arylbenzo[c]phenanthridine Derivatives

A series of novel benzo[c]phenanthridine derivatives 2a , 2b , 2c , 2d , 2e , 2f , 2g , 2h , 2i , 2j , 2k , 2l , 2m and 3a , 3b , 3c , 3d , 3e , 3f bearing an alkylamino side chain at their 6‐position were synthesized. All of the target compounds were confirmed by ¹H NMR, ¹³C NMR, and HRMS, and some of them were also characterized by IR and ¹⁹F NMR. The preliminary bioassays showed that the target compounds displayed fungicidal activities; for example, compound 2l showed 60.0% and 70.0% inhibitive activity against Alternaria solani and Cercospora arachidicola at 50 mg/L, respectively, and some compounds also displayed plant growth‐regulating activities.     

Synthesis of Cytotoxic Isodeoxypodophyllotoxin Analogs

A series of aryltetralin lignans 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i , 7j , 7k , 7l were synthesized as cytotoxic isodeoxypodophyllotoxin analogs. The title compounds 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i , 7j , 7k , 7l were synthesized from the reaction of (+)‐(R )‐4‐[benzo(d )(1,3)dioxol‐5‐ylmethyl]‐dihydrofuran‐2‐(3H )‐one with different arylaldehydes to afford benzyl alcohol analogs and subsequent cyclization with trifluoroacetic acid in dichromethane. The preliminary screening of the compounds against viability of blood cancer human cell line K562 revealed that compounds 7d , 7e , and 7f had higher inhibitory activity at 10 µg/mL concentration compared with etoposide as reference drug.     

Synthesis of Novel Pyrimido[4,5‐b]quinolin‐4‐ones with Potential Antitumor Activity

The 5,6,7,8,9,10‐hexahydro‐2‐methylthiopyrimido[4,5‐b]quinolines 4a , 4b , 4c , 4d , 5a , 5b , 5c , 5d and their oxidized forms 6a , 6b , 6c , 6d , 7a , 7b , 7c , 7d were obtained from the reaction of 6‐amino‐2‐(methylthio)pyrimidin‐4(3H)‐one 2 or 6‐amino‐3‐methyl‐2‐(methylthio)pyrimidin‐4(3H)‐one 3 and α,β‐unsaturated ketones 1a , 1b , 1c , 1d using BF₃.OEt₂ as catalyst and p‐chloranil as oxidizing agent. Some of the new compounds were evaluated in the US National Cancer Institute (NCI), where compound 5a presented remarkable activity against 46 cancer cell lines, with the most important GI₅₀ values ranging from 0.72 to 18.4 μM from in vitro assays.     

Rhodium(II)‐Catalyzed Inter‐ and Intramolecular Enantioselective Cyclopropanations with Alkyl‐Diazo(triorganylsilyl)acetates

The intermolecular cyclopropanation of styrene with ethyl diazo(triethylsilyl)acetate ( 1a ) proceeds at room temperature in the presence of chiral Rh^II carboxylate catalysts derived from imide‐protected amino acids and affords mixtures of trans‐ and cis‐cyclopropane derivatives 2a in up to 72% yield but with modest enantioselectivities (<54%) (Scheme 1 and Table 1). Protiodesilylation of a diastereoisomer mixture 2a with Bu₄NF is accompanied by epimerization at C(1) (→ 3 ). The intramolecular cyclopropanation of allyl diazo(triethylsilyl)acetate ( 8a ), in turn, affords optically active 3‐oxabicyclo[3.1.0]hexan‐2‐one ( 9a ) with yields of up to 85% and 56% ee (Scheme 3 and Table 2). Similarly, the (2Z)‐pent‐2‐enyl derivative 8d reacts to 9d in up to 77% yield and 38% ee (Scheme 3 and Table 3). In contrast, the diazo decomposition of (2E)‐3‐phenylprop‐2‐enyl and 2‐methylprop‐2‐en‐1‐yl diazo(triethyl‐silyl)acetates ( 8b and 8c , resp.) is unsatisfactory and gives very poor yields of substituted 3‐oxabicyclo[3.1.0]hexan‐2‐ones 9b and 9c , respectively (Table 3).     

Synthesis and Reactions of Some Heterocyclic Candidates Based on 2‐Amino‐4,5,6,7‐tetrahydrobenzo[b]thiophene Moiety as Anti‐Arrhythmic Agents

In continuation of our previous work, a series of novel thiophene derivatives 4 , 5 , 6 , 8 , 9 , 9a , 9b , 9c , 9d , 9e , 10 , 10a , 10b , 10c , 10d , 10e , 11 , 12 , 13 , 14 , 15 , 16 were synthesized by the reaction of ethyl 2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carboxylate ( 1 ) or 2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carbonitrile ( 2 ) with different organic reagents. Fusion of 1 with ethylcyanoacetate or maleic anhydride afforded the corresponding thienooxazinone derivative 4 and N‐thienylmalimide derivative 5 , respectively. Acylation of 1 with chloroacetylchloride afforded the amide 6 , which was cyclized with ammonium thiocyanate to give the corresponding N‐theinylthiazole derivative 8 . On the other hand, reaction of 1 with substituted aroylisothiocyanate derivatives gave the corresponding thiourea derivatives 9a , 9b , 9c , 9d , 9e , which were cyclized by the action of sodium ethoxide to afford the corresponding N‐substituted thiopyrimidine derivatives 10a , 10b , 10c , 10d , 10e . Condensation of 2 with acid anhydrides in refluxing acetic acid afforded the corresponding imide carbonitrile derivatives 11 , 12 , 13 . Similarly, condensation of 1 with the previous acid anhydride yielded the corresponding imide ethyl ester derivatives 14 , 15 , 16 , respectively. The structures of newly synthesized compounds were confirmed by IR, ¹H NMR, ¹³C NMR, MS spectral data, and elemental analysis. The detailed synthesis, spectroscopic data, LD₅₀, and pharmacological activities of the synthesized compounds are reported.     

Studies on 4‐Thiazolidinones: Scope of the Reactions of 3‐Aryl‐2‐thioxo‐1,3‐thiazolidin‐4‐ones with Cyanide and Cyanate Ions

Treatment of 3‐aryl‐2‐thioxo‐1,3‐thiazolidin‐4‐ones 1 with CN^? and NCO^? effected the ring cleavage providing [(cyanocarbonothioyl)amino]benzenes 4 and arylisothiocyanates 5 , respectively. Similar treatment of 5‐(2‐aryl‐2‐oxoethyl) derivatives 2 afforded 2,4‐bis(2‐aryl‐2‐oxoethylidene)cyclobutane‐1,3‐diones 6 along with each of the preceding products. Treatment of the respective (E,Z)‐5‐(2‐aryl‐2‐oxoethylidene) analogues 3b and 3c with CN^? gave 4b and 4c and 2‐(arylcarbonyl)‐2‐methoxy‐4‐oxopentanedinitriles 7b and 7c , in addition to 3,6‐bis[2‐(4‐chlorophenyl)‐1‐methoxy‐2‐oxoethylidene]‐1,4‐dithiane‐2,5‐dione 8c , which has been generated from 3c . Reactions of 3c or 3d with NCO^? provided 5c or 5d , together with 8c or 8d as pure isomers. In the formation of the MeO products 7 and 8 , the solvent (MeOH) has participated. Structures of these products are based on microanalytical and spectroscopic data. Rationalizations for the above transformations are given.     

Synthesis of Novel Pyridothienopyrimidines,Pyridothienopyrimidothiazines, Pyridothienopyrimidobenzthiazoles and Triazolopyridothienopyrimidines

The reaction of 3‐amino‐4,6‐dimethylthieno[2,3‐b]pyridine‐2‐carboxamide (1a) or its N‐aryl derivatives 1b‐d with carbon disulphide gave the pyridothienopyrimidines 2a‐d , whilst when the same reaction was carried out using N¹‐arylidene‐3‐amino‐4,6‐dimethylthieno[2,3‐b]pyridine‐2‐carbohydrazides (1e‐h) , pyridothienothiazine 3 was obtained. Also, refluxing of 1b‐d with acetic anhydride afforded oxazinone derivative 4 . Compounds 2a and 2b‐d were also obtained by the treatment of thiazine 3 with ammonium acetate or aromatic amines, respectively. When compound 2a was allowed to react with arylidene malononitriles or ethyl α‐cyanocinnamate, novel pyrido[3″,2″:4′,5′]thieno[3′,2′:4,5]pyrimido[2,1‐b][1,3] thiazines 5a‐c were obtained. Treatment of 2b‐d with bromine in acetic acid furnished the disulphide derivatives 6a‐c . U.V. irradiation of 2b‐d resulted in the formation of pyrido[3″,2″:4′,5′]thieno[3′,2′:4,5]pyrimido[2,1‐b]benzthiazoles 7a‐c . The reaction of 2a‐d with some halocarbonyl compounds afforded the corresponding S‐substituted thiopyrido thienopyrimidines 8a‐j . Compound 8b was readily cyclized into the corresponding thiazolo[3″,2″‐a]‐pyrido[3′,2′:4,5]thieno[3,2‐d]pyrimidine 9 upon treatment with conc. sulphuric acid. Heating of 2a,b with hydrazine hydrate in pyridine afforded the hydrazino derivatives 11a,b . Reaction of ester 8c with hydrazine hydrate in ethanol gave acethydrazide 10 . Compounds 10 and 11a,b were used as versatile synthons for other new pyridothienopyrimidines 12–15 as well as [1,2,4] triazolopyridothienopyrimidines 16–19.     

Synthesis and Herbicidal Activity of 5‐Alkyl(aryl)‐3‐[(3‐trifluoromethyl)anilino]‐4,5‐dihydro‐1H‐pyrazolo[4,3‐d]pyrimidin‐4‐imines

A series of novel 5‐alkyl(aryl)‐3‐[(3‐trifluoromethyl)anilino]‐4,5‐dihydro‐1H‐pyrazolo[4,3‐d]pyrimidin‐4‐imines were designed and synthesized by the multistep reactions. 1 reacted with 3‐(trifluoromethyl)aniline to obtain N,S‐acetals 2 in the presence of 10 mol% DBU. 2 reacted with hydrazine to form 5‐amino‐3‐[(3‐trifluoromethyl)anilino]‐1H‐pyrazol‐4‐ nitrile 3 , the target compounds 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j , 5k , 5l , 5m were obtained by the reaction of 3 with triethyl orthoformate followed by the cyclization of 4 with various amines. Their structures were confirmed by IR, ¹H NMR, EI‐MS, and elemental analyses. The preliminary bioassay indicated that some of them displayed moderate herbicidal activity against dicotyledonous weed Brassica campestris L at the concentration of 100 mg/L. For example, compounds 5f , 5g , 5h , and 5j possessed 60.1%, 63.4%, 67.1%, and 61.3% inhibition against Brassica campestris L at the concentration of 100 mg/L.     

Synthesis of 32‐phenyl‐substituted methyl E/Z‐pyropheophorbide‐a's from methyl E/Z‐pyropehophorbide‐a 131‐ketoximes

Methyl E/Z‐pyropheophorbide‐a 13¹‐ketoximes 2a,b and their O‐acetyl derivatives 3a,b were oxidized with osmium(VIII) oxide to give aldehydes 4a,b and 5a,b , respectively. The Wittig reactions of the aldehyde chlorines 4a,b and 5a,b with benzyltriphenylphosphonium chloride were performed to form the corresponding methyl (3¹E/Z,13¹E/Z)‐3²‐phenylpyropheophorbide‐a 13¹‐ketoximes 6aa‐bb and their O‐acetyl derivatives 7aa‐bb ; hydrolysis of these ketoximes 6aa,ba and 6ab,bb in formic acid produced methyl (E/Z)‐3²‐phenylpyropheophorbide‐a's 8a,b .     

Synthesis and pharmacological properties of N‐substituted‐N′‐(4,6‐dimethylpyrimidin‐2‐yl)‐thiourea derivatives and related fused heterocyclic compounds

A series of new N‐Substituted‐N′‐(4,6‐dimethylpyrimidin‐2‐yl)‐thiourea derivatives ( 3a , 3b , 3c , 3d ) and related fused heterocyclic compounds ( 4a , 4b , 4c , 4d ) were synthesized using tetrabutylammonium bromide as phase transfer catalyst (PTC). N‐[(2E)‐5,7‐dimethyl‐2H‐[1,2,4] thiadiazolo [2,3‐a] pyrimidin‐2‐ylidene] derivatives ( 4a , 4b , 4c , 4d ) were prepared by oxidative cyclization of 3a , 3b , 3c , 3d . The structures of these novel compounds were characterized by IR, ¹H NMR, ¹³C NMR, mass spectrometry, and the elemental analysis. The crystal structures were determined from single crystal X‐ray diffraction data. The results indicated that the compounds possessed a broad spectrum of activity against the tested microorganisms and showed higher activity against fungi than bacteria. Compounds 3d and 3a exhibited the greatest antimicrobial activity. J. Heterocyclic Chem., 2011.     

Optical Activity 1,5‐Substituted‐1,3,5‐hexahydrotriazine‐2‐N‐nitroimines: Synthesis and Insecticidal Activity

Twelve novel neonicotinoid analogues 1‐(2‐furfuryl)‐5‐substituted‐1,3,5‐hexahydrotriazine‐2‐N‐nitroimines 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k , 3l were synthesized. Their structures were characterized by ¹H NMR, IR, and elemental analysis. The preliminary bioassay tests showed that all the title compounds gave ≥90% mortality against Nilaparvata lugen 500 mg/L.