5-(Trimethylstannyl)-2H-pyran-2-one and 3-(Trimethylstannyl)-2H-pyran-2-one: New 2H-Pyran-2-one Synthons

5-(Trimethylstannyl)-2H-pyran-2-one (11) and 3-(trimethylstannyl)-2H-pyran-2-one (30), readily prepared from the corresponding bromo-2H-pyran-2-ones, undergo Pd(0)-catalyzed coupling reactions with a variety of enol triflates to give 5- and 3- substituted 2H-pyran-2-ones, respectively. This reaction is applicable to the enol triflates of 14beta-hydroxy-17-ketosteroids, and therefore may prove useful in convergent syntheses of lucibufagins and bufadienolides.     

Enamine Configuration of 5-Methyl-2-phenyl-4-[（Z）-3-tolylamino-phenylmethylene]pyrazol-3（2H）-one

1 INTRODUCTION In contrast to the old-line academic and practical studies of 1-phenyl-3-methyl-4-benzoyl-5-pyrazo- lone (PMBP) on the metal coordination chemistry[1], the complexes of β-ketoamines derivated from PMBP received little attention due to its complicated com- plexation. However, in recent years, there has a sudden growth of this area as a result of its timely interest in biological activities[2]. Recently, a series of β-ketoamines[3] containing PMBP have been prepared fro…     

Synthesis and biological activity of new 2-[(3-aminopropyl)dimethyl-silyl]-5-trialkylgermylfurans

New highly cytotoxic 3-aminopropyl derivatives of 2-dimethylsilyl-5-trialkylgermylfuran (IC₅₀ 1−3 μg⋅ml⁻¹) have been prepared by hydrosilylation of heterocyclic N-allylamines with the corresponding hydrosilane in the presence of Speier’s catalyst. The influence of the amine structure and alkyl substituent at the germanium atom on the cytotoxicity has been investigated.     

Synthesis and Crystal Structure of 5-Methyl- 2-phenyl-4-[（2-p-bromophenylamino）-furylmethylene]-3（2H）-one

A novel 4-heterocyclic acylpyrazolone-based Schiff base compound 5-methyl- 2-phenyl-4-[（2-p-bromophenylamino）-furylmethylene]-3（2H）-one （C21H16N3O2Br） has been synthesized by the reaction of 1-phenyl-3-methyl-4-（α-furoyl）-pyrazolone-5 （HPMαFP） and p-bromoaniline. Elemental analysis, IR spectra and X-ray single-crystal diffraction were carded out to determine the composition and crystal structure of the compound. Crystal data： triclinic system, space group P1^-, a = 9.0936（3）, b = 9.8067（4）, c = 11.6863（4） A, α = 102.512（10）, β = 90.9630（10）, γ = 114.327（10）°, Mr= 422.28, Z= 2, F（000） = 428.0, V= 920.46（11）A^3, Dc = 1.524 g/cm^3,μ = 2.254mm^-1, R = 0.0476 and wR = 0.1318 for 9389 independent reflections （Rint = 0.0122） and 3281 observed reflections （I 〉 2σ（I））. Structural analysis indicates that the compound exists in an amine-one form.     

Synthesis of 1-Amino-6,7-dihydro-7-(hydroxymethyl)-4-nitro-pyrrolo[1,2-f]pyrimidin-3-(5H)-one from 2-Amino-6-methylpyrimidin-3-one

The synthesis of previously unreported 1-amino-6,7-dihydro-7-(hydroxymethyl)-4-nitropyrrolo[1,2-f]pyrimidin-3-(5H)-one starting from 2-amino-6-methylpyrimidin-3-one is described.     

Stereoselective synthesis of (6S)-5,6-dihydro-6-[(2R)-2-hydroxy-6-phenylhexyl]-2H-pyran-2-one

A stereoselective synthesis of (6S)-5,6-dihydro-6-[(2R)-2-hydroxy-6-phenylhexyl]-2H-pyran-2-one is reported. The strategy utilizes an olefin cross-metathesis, syn-benzylidene acetal formation and a preferential (Z)-Wittig olefination reaction and lactonization as the key steps.     

Enantiomeric separation of novel anticancer agent 5-hydroxy-3-(4-methoxyphenyl)-2-(3,4,5-trimethoxyphenyl)-cyclopent-2-en-1-one

The enantiomers of 5-hydroxy-3-(4-methoxyphenyl)-2-(3,4,5-trimethoxyphenyl)-cyclopent-2-en-1-one, a novel anticancer agent, were separated by derivatisation with caronaldehyde, separation of the resulting diastereoisomers of the corresponding esters by silica gel column chromatography and regeneration of alcohols (S)-5-hydroxy-3-(4-methoxyphenyl)-2-(3,4,5-trimethoxyphenyl)-cyclopent-2-en-1-one and (R)-5-hydroxy-3-(4-methoxyphenyl)-2-(3,4,5-trimethoxyphenyl)-cyclopent-2-en-1-one under aqueous conditions. The absolute configuration of the enantiomers was determined by 1H NMR studies of the corresponding Mosher esters. Alternatively, the enantiomers were separated by preparative HPLC to collect the (S)- and (R)-5-hydroxy-3-(4-methoxyphenyl)-2-(3,4,5-trimethoxyphenyl)-cyclopent-2-en-1-ones with high purity which was comparable with that obtained by the chemical method. The details of these methods have been presented herein.     

1,5-Dimethy-4-[(3-nitro-benzylidene)-amino]-2-pheyl-1,2-dihydro-pyrazol-3-one

1INTRODUCTION Antipyrine(2,3-dimethyl-1-phenyl-5-pyrazolone)and its derivatives exhibit a wide range of biological activities and applications[1~3].Antipyrine shows mi-nimal protein binding and is rapidly and completely absorbed from the gastrointestinal tract and exten-sively metabolized by the cytochrome P450liver en-zymes[4].Estimates of half-life and systemic cleara-nce of antipyrine have been used for the in vivo asse-ssment of hepatic drug oxidation in different spe-cies[5].Owing to…     

2-[(吡啶-3-基)甲氨基]-1H-咪唑-4(5H)-酮衍生物的合成及其抑菌活性

本文以2-硫代乙内酰脲、取代苯甲醛、碘甲烷、吡啶甲胺等为原料,经Knoevenagel缩合、甲基化和取代反应,合成了一系列5-取代苯亚甲基-2-[(吡啶-3-基)甲氨基]-1H-咪唑-4(5H)-酮(3a~3i),其结构经IR、~1H NMR、~13C NMR和HRMS确证。初步抑菌活性试验表明,在药剂浓度为100μg/m L时,目标化合物对灰霉菌均有中等抑制活性,抑制率为69.5%~83.2%;在相同浓度下大部分化合物对菌核菌有较高的抑制活性,抑制率为87.9%~100%,其活性高于对照药三唑酮和百菌清。     

Synthesis of 1-[(2-hydroxy-1-(hydroxymethyl)ethoxy)methyl]-1,2,4-triazole-3- and 5-carboxamides

Coupling of trimethylsilyl derivative of methyl 1,2,4-triazole-3-carboxylate with 2-$\text{O}$-(chloromethyl)-1,3-di-$\text{O}$-benzyl glycerol, followed by amination and removal of the protecting groups afforded 1-[(2-hydroxy-1-(hydroxymethyl)ethoxy)methyl]-1,2,4-triazole 3- and 5-carboxamides, 1a and 1b, respectively.