N-(5-芳基-1,3,4-嗯二唑-2-基)-N''-α-萘乙酰基硫脲的合成及杀菌活性

从α-萘乙酸出发,合成酰基异硫氰酸酯,然后与2-氨基-5-芳基-1,3,4-嗯二唑反应合成了8个新的酰基硫脲类化合物 Ⅱa~Ⅱh 。所有化合物的结构均经元素分析、红外光谱、核磁共振氢谱和质谱确认。同时对6种病原菌进行了生物活性测试,结果发现,在50 mg/L下,所有目标化合物对黄瓜灰霉病菌Botrytis cinereapers的抑制效果较好,除 Ⅱa 外,其他化合物抑制率都达到80%以上。     

Synthesis and characterisation of some 4‐keto derivatives of 1,3,4(2H)‐isoquinolinetrione redox mediator herbicides

Derivatives of 2‐ethyl‐1,3,4(2H)‐isoquinolinetrione in which the 4‐keto group has been modified to (Z)‐oxime, (E)‐ and (Z)‐O‐methyl oxime, (Z)‐N,N‐dimethyl hydrazone, cyano‐imine and dicyanomethylene moieties have been prepared and evaluated as redox mediator herbicides. All of the compounds have the free‐radical properties required to function as redox mediators, as determined by cyclic voltammetry, though only the O‐methyl oximes, the N,N‐dimethyl hydrazone and the cyano‐imine have reduction potentials in the range required to stimulate the light‐dependent consumption of oxygen at photosystem I in isolated chloroplasts. The O‐methyl oximes and the cyano‐imine are fast‐acting post‐emergence herbicides, producing symptoms of rapid desiccation; the (E)‐O‐methyl oxime is the most active herbicide, being somewhat more potent than the parent isoquinolinetrione. Hydrolysis studies indicate that it is unlikely that any compound generates the parent isoquinolinetrione in vivo. Attempts to explain differences between in vitro and in vivo activities using hydrolytic stabilities and physical properties were unsuccessful, and it was concluded that these factors probably play a less significant role in moderating the herbicidal activity of isoquinolinetrione derivatives than originally thought. © 2000 Society of Chemical Industry     

The toxic and anti-feedant activity of 2H-pyridazin-3-one-substituted 1,3,4-oxadiazoles against the armyworm Pseudaletia separata (Walker) and other insects and mites

The toxicities and anti-feedant activities of thirteen asymmetrical 1,3,4-oxadiazoles containing a 2H-pyridazin-3-one group were investigated. The compounds were shown to possess considerable activity in retarding the development of larvae of a number of Lepidoptera, but they were all inactive against Homoptera, Diptera and Acarina. The compounds had powerful anti-feedant activity comparable with that of azadirachtin. The toxic symptoms of the poisoned larvae indicated that the compounds were novel insect growth regulators with a mode of action that might be similar to the chitin-synthesis inhibition of oxadiazole compounds and/or the juvenile hormone effect of pyridazinone compounds.     

1-(2-酰氧基-4,5-亚甲二氧基)苯基-2-甲基丙烯酮类化合物的合成及抑菌活性

以具有较高抑菌活性的卡枯醇衍生物1-(2-羟基-4,5-亚甲二氧基)苯基-2-甲基丙烯酮为原料,设计合成了14个未见文献报道的1-(2-酰氧基-4,5-亚甲二氧基)苯基-2-甲基丙烯酮类(2a～2n)化合物,其结构经电喷雾串联质谱(ESI-MS)和核磁共振氢谱确证。初步生物活性测试结果表明,在100 mg/L下,目标化合物对5种供试病原菌均具有较高的抑菌活性,其中, 2b和2d 对番茄灰霉病菌Botrytis cinerea和小麦赤霉病菌Fusarium graminearum的抑制率达100%。     

N-1,3,4- 口 恶 二唑基-N''-对溴苯氧乙酰基硫脲的合成及其抑菌活性

从对溴苯氧乙酸出发,先合成中间体酰基异硫氰酸酯,该中间体与2-氨基-5-芳基-1,3,4- 口 恶 二唑反应合成了10个新的苯氧乙酰基硫脲类化合物,其结构经元素分析、红外光谱、核磁共振氢谱和质谱确认。初步生物活性测试结果表明,在50 mg/L浓度下,所有目标化合物对水稻纹枯病菌Rhizatonia solani和黄瓜灰霉病菌Botrytis cinereapers的抑制率均达85％以上,部分化合物对黄瓜灰霉病菌的抑制率达100%。     

1,3,4(2H)‐Isoquinolinetriones: evaluation of amino‐substituted derivatives as redox mediator herbicides

Amino‐substituted derivatives of 2‐ethyl‐1,3,4(2H)‐isoquinolinetrione have been prepared with the aim of enhancing their hydrolytic stabilities relative to other isoquinolinetriones, and hence potentially improving their herbicidal effects. 5‐Amino‐2‐ethyl‐1,3,4(2H)‐isoquinolinetrione has been shown to be 12 and 8 times more stable towards hydrolysis than the isomeric 7‐ and 8‐amino derivatives, respectively, and 120 times more stable than 2‐ethyl‐1,3,4(2H)‐isoquinolinetrione itself. Pulse radiolysis studies have shown 5‐amino‐2‐ethyl‐1,3,4(2H)‐isoquinolinetrione to have free‐radical properties which could enhance the generation of superoxide radicals in plants. The compound is a potent stimulator of the light‐dependent consumption of oxygen at photosystem I in isolated chloroplasts and also shows high activity in isolated leaf discs. Evidence is presented which indicates that the rate of foliar uptake is a major factor affecting herbicidal activity for this compound. © 2000 Society of Chemical Industry     

5-(2-呋喃基)-1,3-环己二酮衍生物的合成及除草活性

为了研究环己三酮类除草剂结构与活性的关系,以2-呋喃甲醛为起始原料,经过与丙酮的羟醛缩合(aldol condensation)反应、与丙二酸二乙酯的迈克尔加成反应、以及分子内的羟醛缩合环化反应,最后与酰氯发生重排反应合成了一系列新的5-(2-呋喃基)-1,3-环己二酮衍生物,所有目标化合物的结构均经过核磁共振氢谱、碳谱及高分辨质谱的确证。初步除草活性测定结果表明,与天然的AB5046A相比,2-苯甲酰基-5-(2-呋喃基)衍生物的活性明显降低,而2-乙酰基和丙酰基衍 生物则显示出更高的除草活性,如化合物 T3 在100 μ g/mL下对油菜生长的最高抑制率达82.9%。     

6,7-亚甲二氧基硫代苯并二氢吡喃-4-酮衍生物的合成及抑菌活性

以亚甲二氧基苯为起始原料,经过溴化、硫化、环化等反应合成了19个未见文献报道的6,7-亚甲二氧基硫代苯并二氢吡喃-4-酮衍生物,其结构均经核磁共振氢谱和质谱确认。初步抑菌活性测试结果表明,在50 mg/L下,目标化合物对供试7种植物病原菌均有不同程度的抑制作用,其中化合物5b、5i、5k和5l对马铃薯干腐病菌 Fusarium solani的抑制率均达75%以上,5h和5i对番茄灰霉病菌Botrytis cinerea的抑制率分别是67.7%和70.4%。     

新型N-芳基-2-((5-((4,6-二甲基嘧啶-2-基)硫甲基)-1,3,4-噻二唑-2-基)硫)乙酰胺类化合物的合成及杀菌活性

为寻找新型杂环活性化合物,通过活性亚结构拼接,以硫脲和乙酰丙酮为起始原料合成4,6-二甲基嘧啶-2-硫醇,随后经酯化、肼化、环化和缩合反应,设计并采用微波辅助合成了10个新型N-芳基-2-（（5-（（4,6-二甲基嘧啶-2-基）硫甲基）-1,3,4-噻二唑-2-基）硫）乙酰胺类化合物,其结构通过核磁共振氢谱和碳谱、红外光谱、质谱及元素分析确认。初步生物活性测试结果表明,在50 mg/L下,大部分目标化合物对植物病原真菌具有一定的抑制活性,其中化合物8h对黄瓜炭疽病菌Colletotrichum orbiculare的抑制率达77.3%。     

(4-亚甲基-5-羰基-3-四氢呋喃基)-苯甲酸甲酯衍生物的合成及其杀菌活性

为了探索天然产物Cedarmycins衍生物的结构与活性关系,以α-亚甲基-β-羟甲基-γ-丁内酯为起始原料,经过与不同取代的羧酸缩合,合成了19个新的(4-亚甲基-5-羰基-3-四氢呋喃基)-苯甲酸甲酯衍生物。杀菌活性测定结果表明,该类衍生物具有广谱的杀菌活性,尤其对水稻纹枯病菌Rhizoctonia solani和辣椒疫霉Phytophthora capsici显示出很强的杀菌活性,其中化合物2e(R=2,4-2Cl)对这2种病菌的EC50值约为1.6 mg/L。     

4-取代-2-[(3-三氟甲基)-苯乙烯基]-1,3,4-噁二嗪-5-酮的合成及其生物活性

以3-(3-三氟甲基苯基)-丙烯酸为起始原料,设计并合成了14个4-取代-2-(3-三氟甲基)苯乙烯基-1,3,4-噁二嗪-5-酮衍生物,其化学结构经核磁共振氢谱及元素分析确证。初步的生物活性测定结果表明,该类化合物具有良好的杀虫活性,其中化合物 D-2,D-3,D-4,D-8 在质量浓度为50 mg/L时,对淡色库蚊Culex pipiens pallens的致死率分别为91.7% ,86.1% ,85.5%和93.9%。     

5-亚环己基-咪唑-2,4-二酮及其衍生物的合成及杀菌活性

以环己酮及其衍生物和2-硫代-咪唑-2,4-二酮及咪唑-2,4-二酮膦酸酯为起始原料,经Knoevenagel 缩合反应和Wittig-Horner反应合成了10个5-亚环己基-咪唑-2,4-二酮系列衍生物,其中7个为新化合物,其化学结构经1H NMR、IR和MS确证。初步生物活性测定结果表明:在50 μg/mL 下,部分目标化合物对油菜菌核病菌 Sclerotinia scleotiorum 显现出良好的抑制活性,其中 7I和7J 的EC50分别为8.06 和8.48 μg/mL。     

Synthesis and anti-mildew activity of 5-(2-aroyl)aryloxymethyl-2-phenyl-1 ,3,4-oxadiazoles against downy mildew of pearl millet

A manipulatively simple, rapid, high-yielding and environmentally benign method for the integration of a heterocyclic ring, 1,3,4-oxadiazole, at the benzophenone nucleus has been achieved through intramolecular cyclization of substituted aroylaryloxyacetohydrazides to substituted 5-(2-aroyl)aryloxymethyl-2-phenyl-1,3,4-oxadiazoles under solventless 'dry' conditions using montmorillonite K10 clay and microwave irradiation. A comparison is made of the microwave-accelerated reaction with conventional heating conditions. Certain of the derivatives tested showed significant anti-mildew activity against Sclerospora graminicola (Sacc) Schroeter, the downy mildew pathogen of pearl millet.