Application of Commercially Available Anhydrous Potassium Fluoride for a Convenient Synthesis of Ketene Dithioacetals
作者:Sabir H. Mashraqui、Harini Hariharasubrahmanian
DOI:10.1039/a901038f
日期:——
Commercially available anhydrous KF without activation or solid support promotes condensation between activemethylene compounds, carbon disulfide and an alkylatingagent in dry DMF to allow the preparation of a variety of ketene dithioacetals in fair to good yields under ambient conditions.
Multicomponent reaction of malononitrile, carbon disulphide and various benzyl halides was developed as an efficient strategy for the synthesis of 2-(bis(benzylthio)methylene)malononitrile derivatives via two different procedures: (a) in the presence of K 2 CO 3 as a base in acetonitrile and (b) under solvent-free conditions in the presence of triethylamine. Higher yields with shorter reaction times were
丙二腈,二硫化碳和各种苄基卤化物的多组分反应被开发为通过两种不同的方法合成2-(双(苄硫基)亚甲基)丙二腈衍生物的有效策略:(a)在K 2 CO 3存在下乙腈中的碱和(b)在三乙胺存在下的无溶剂条件下。从后面的过程中获得了更高的产率和更短的反应时间。评价了所有衍生物对22种致病菌的抑制活性,包括革兰氏阴性和革兰氏阳性菌株。根据抗菌谱测试,硫醚4b表现出广谱抗菌活性。进行DFT计算(B3LYP / 6-311 ++ G **),以确定药物-受体相互作用的类型。
An ?-hydrazinoalkylphosphonate as building block for novelN-phosphonoalkylheterocycles
α-Hydrazinoalkylphosphonate 3 is a useful buildingblock for the syntheses of novel N-phosphonoalkylheterocycles. N-phosphonoalkylpyrazoles 8 and 9 were prepared by the cyclization reaction of 3 with multifunctioned ethenes 5 and 6 in ethanol under reflux. N-Phosphonoalkyltriazole 10 was synthesized from 3 with N-dimethylthiomethylene benzoyl amide 4 in ethanol under reflux. The structures were confirmed
catalytic sodium wolframate led to the formation of 6-alkylsulfonylpyridine derivatives 5, which could be further derivatized in the 6-position by nucleophilic reactions with phenols or amines to give multisubstitutedpyridine compounds 8. Bioassays indicated that some of the compounds of the type 8 have good herbicidalactivity at a dose of 100 mg/L on the roots of oil rape and barnyard grass. J. Heterocyclic
HETEROAROMATIZATION WITH KETENE DITHIOACETALS: PART II. SYNTHESIS OF SOME NOVEL 5-AMINOPYRAZOLE-3-CARBONITRILE, 3-CARBOXAMIDE AND PYRAZOLO[3,4-d]PYRIMIDIN-4-ONE DERIVATIVES AS ANTIMICROBIAL AGENTS
作者:Saber M. Hassan、Hussein A. Emam、Mahmoud M. Abdelall
DOI:10.1080/10426500108040260
日期:2001.8
Abstract Ketene dithioacetals la-d are utilized for synthesis of pyrazoledithiocarboxylates 2a-d and arylaminopyrazoles 4a,b with two different substituents (o-ethoxy and p-diethylminosulfonyl) in aryl residue. Some transformation of the dithioesters 2 ate described. After that arylaminopyraroles 4a,b are converted to pyrazolopyrimidine derivatives 8–11.