Design,Synthesis and Insecticidal Activities of Novel 5-Alkoxyfuran-2(5H)-one Derivatives

A series of novel 5?alkoxyfuran-2(5H)-one derivatives was synthesized, and characterized by 1H NMR, 13C NMR and HRMS. Biological activities of all the title compounds were evaluated systematically. Preliminary bioassays indicated that most of the compounds exhibited moderate insecticidal activities against Aphis craccivora and Nilaparvata lugens at 100 mg/L. Compounds 4h and 4w exhibited 100% mortality rate against Aphis craccivora at 100 mg/L, and compound 4h exhibited good mortality rate against Aphis craccivora and Nilaparvata lugens (60% and 75%, respectively) even at 4 mg/L. The results demonstrated the impact of various chemical groups on insecticidal activities and provided a potential clue for further exploring novel high-effective broad-spectrum insecticides.     

5-甲基-2，3-二苯基-1，5-苯并硫氮杂卓-4(5H)-酮的合成

以2-甲硫基苯胺为原料,通过酰化、碘环化以及Suzuki交叉偶联反应,合成了5-甲基-2,3-二苯基-1,5-苯并硫氮杂卓-4(5H)-酮。 分别考察了催化剂对酰化反应、溶剂对碘环化反应的影响,以及催化剂、配体、碱和温度等因素对Suzuki交叉偶联反应的影响,在最佳的反应条件下,反应总收率为68.5%,中间产物和目标产物的结构经IR、NMR和MS等测试技术得以确证。     

3-碘-5-甲基-1,5-苯并硫氮杂(艹卓)-4(5H)-酮的合成

以2-甲基硫代苯胺为原料,通过酰化反应、碘环化反应合成了3-碘-5-甲基-1,5-苯并硫氮杂(艹卓)-4(5H)-酮,总收率86.3%,其结构经NMR,IR和MS表征.     

Synthesis of methyl derivatives of new polycyclic systems of 4H-furo[3,2-g]pyrrolo[3,2,1-ij]quinolin-4-one,of 1H,5H- and 3H,5H-benzofuro[5,6,7-ij]quinolizin-5-one

The synthesis of new tetracyclic 4H-furo[3,2-g]pyrrolo[3,2,1-ij]quinolin-4-ones, 15–17 , 1H,5H-benzofuro[5,6, 7-ij]quinolizin-5-ones, 18–20 , and 3H,5H-benzofuro[5,6,7-ij]quinolizin-5-ones, 21–23 is described. The planarity of the structure of benzofuroquinolizin-5-one 18 was determined by X-ray single-crystal analysis.     

5-(1-Alkenyl)-1, 3, 4-oxadiazol-2(3H)-one

3-(2-alkenoyl)-thiocarbazic acid O-methyl esters 1 are desulfurated by bromine and the unknown intermediates are transformed by alkali to 5-(1-alkenyl)-1, 3, 4-oxadiazol-2(3H)-ones ( 2 ). This type of oxadiazolone substitution is not realizable by the common ring closure of hydrazides with phosgene due to pyrazolidinone ring closure of unsaturated acids with hydrazine.     

Synthesis of 11-aza-5H-benzophenoxazin-5-one and 11-Aza-5H-pyridophenoxazin-5-one derivatives

The 1,6-disubstituted- and 4,6-disubstituted-11-aza-5H-benzo[a]phenoxazin-5-one as well as 6-substituted-11-aza-5H-pyrido[a]phenoxazin-5-one derivatives were prepared by the condensation of 2-amino-3-hydroxypyridine with 5-substituted-2,3-dihalogeno-1,4-naphthoquinones and 6,7-dibromo-5,8-quinolinequinone respectively. The resulting compounds were subjected to reduction, acetylation, dehalogenation and reaction with aniline.     

2-Methyl-s-triazolo[1,5-b]isoquinolin-5(10H)-one

Acetamidrazone hydrochloride reacts with homophthalic anhydride to give 3-o-carboxybenzyl-5-methyl-1,2,4-triazole 1, which can be cyclised to 2-methyl-s-triazolo[1,5-b] isoquinolin-5(10H)-one 2. Reduction with lithium aluminium hydride gives 5,10-dihydro-2-methyl-s-triazolo [1,5-b] isoquinoline, while condensation with aromatic aldehydes gives 10-arylmethylene derivatives. Coupling with arenediazonium salts gives the 10-arylhydrazones of 5,10-dihydro-2-methyl-s-triazolo [1,5-b] isoquinoline-5,10-diones, while condensation with p-nitrosodimethylaniline gives the 10-imino derivative. Alkylation of 2 produces the corresponding 10,10-dialkyl derivatives.     

Synthesis of (5S)-5-methylfuran-2(5H)-one and its dihydro derivative

(5S)-5-Methylfuran-2(5H)-one and (5S)-5-methyltetrahydrofuran-2-one were synthesized starting from L-lactic acid ethyl ester.     

Mechanism of the recyclization of 2-amino-5-benzylidene-1,3-thiazol-4(5H)-one into derivatives of 2-amino-5-benzylidene-1,5-dihydro-4H-imidazol-4-one

Mechanisms are given for reactions taking place upon heating 2-amino-5-benzylidene-1,3-thiazol-4(5H)-one in a medium consisting of a secondary amine. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 111–114, January, 2008.     

Design,synthesis, antimicrobial evaluations and in silico studies of novel pyrazol-5(4H)-one and 1H-pyrazol-5-ol derivatives

A new series of 1,4-disubstituted 3-methylpyrazol-5(4H)-one derivatives were synthesized by reacting various substituted aromatic aldehydes with 3-methylpyrazol-5(4H)-one derivatives through Knoevenagel condensation by conventional as well as by exposure to microwave irradiations. After that newly synthesized compounds of 1,4-disubstituted 3-methyl-1H-pyrazol-5-ol were prepared from these derivatives by reduction reaction of sodium borohydride at 0–5 °C. Sixty-four heterocyclic compounds containing a pyrazole moiety were synthesized with good to excellent yields (51 to 91%). Compounds (3d, 3m, 4a, 4b, 4d, and 4g) showed potent antibacterial activity against MSSA (Methicillin-susceptible strains of Staphylococcus aureus) and MRSA (Methicillin-resistant strains of Staphylococcus aureus) with MIC (the minimum inhibitory concentration) ranging between 4 and 16 µg/mL as compared to ciprofloxacin (MIC = 8–16 µg/mL). Compounds (4a, 4h, 4i, and 4l) showed potent antifungal activity against Aspergillus niger with MIC ranging between 16 and 32 µg/mL as compared to fluconazole (MIC = 128 µg/mL). In particular, compound 4a exhibited the strongest activity among the synthesized compounds in both bacterial and fungal strains with MIC ranging between 4 and 16 µg/mL. Furthermore, the nine most active compounds showed a good ADMET (absorption, distribution, metabolism, excretion, and toxicity) profile in comparison to ciprofloxacin and fluconazole as reference drugs. Molecular docking predicted that DHFR (dihydrofolate reductase) protein from Staphylococcus aureus and NMT (N-myristoyl transferase) protein from Candida albicans are the most suitable targets for the antimicrobial activities of these potent compounds.     

Sulfides,sulfones, and sulfoxides of the furan-2(5H)-one series. synthesis and structure

A number of 4- and 5-R-sulfanylfuran-2(5H)-one derivatives were synthesized, and their oxidation with various reagents was studied. The corresponding sulfones were obtained using hydrogen peroxide in acetic acid. 4-R-sulfanyl derivatives were selectively oxidized to sulfoxides with m-chloroperoxybenzoic acid. The molecular and crystal structures of some new sulfones and sulfoxides were determined by X-ray analysis.     

Alkylation of 5-nitro-l,2,4-triazol-3-one

The alkylation of 5-nitro-1,2,4-triazol-3-one with dialkyl sulfates and alkyl iodides has given N-alkyl-5-nitro-1,2,4-triazolones. The structure of the compounds obtained has been shown by independent synthesis via the corresponding N-alkyl derivatives of 1,2,4-triazol-3-one.     

Reaction of 3,4-Dichloro-5-methoxyfuran-2(5H)-one with 1,2-Organylbis(diphenylphosphines)

The reactions of 3,4-dichloro-5-methoxyfuran-2(5H)-one with 1,2-ethylenebis(diphenylphosphine) and 4,5-bis(diphenylphosphinyl)-2-phenylpyridazin-3(2H)-one involve substitution of both chlorine atoms with ³-P atoms to form unstable diphosphonium bicyclic salts which in the course of the reaction undergo an unusual fragmentation to give finally mono- and tricyclic diphosphoniacyclohexane structures.     

Molecular structure of a zwitter-ionic 2-piperidinyl-4-dinitromethyl-1,3,5-triazin×(1H, 5H)-6-one salt

A zwitter-ionic salt 2-piperidinyl-4-dinitromethyl-1,3,5-triazin(1H,5H)-6-one is studied by the single crystal X-ray analysis. The crystals are monoclinic: a = 11.526(1) Å, b = 9.211(1) Å, c = 12.182(1) Å; β = 110.69(1)°, V = 1209.9(2) ų, space group P2₁/n; Z = 4, ρ_calc = 1.560 g/cm³. The transformation of the dinitromethyl fragment conformation, the conjugation of one of nitrogroups with the 1,3,5-triazine ring, and an intramolecular hydrogen bond are revealed. The 1,3,5-triazine cycle is strongly distorted due to lactam-lactim tautomerism.