SYNTHESIS OF 1, 6-DIEPI-DIHYDROARTEANNUIC ACID

R(+)-Citronellal was converted into a key intermediate, (unsaturated ketone 5)in three steps, which led to 6 having the frame of arteannuic acid through intramolecular ene reaction.Further modification of 6afforded 1, 6-epimer of dihydroarteannuic acid.The configuration of 7 was determined by X-ray diffraction analysis.     

VERSATILE SYNTHESIS AND FUNGICIDAL ACTIVITIES OF 6-AMINO-3- ALKYLTHIO-1,5-DIHYDRO-1-PHENYL-PYRAZOLO [3,4-D]PYRIMIDIN-4-ONE DERIVATIVES

A series of new 6-alkylamino-3-alkylthio-1-phenyl-1H-pyrazolo[3,4-d] pyrimidin-4(5H)-one derivatives 5 and 6 have been rapidly synthesized by a novel solution-phase regioselective synthetic method. Treatment of pyrazole o-aminoester 1 with dibromotriphenylphosphorane gave iminophosphorane 2, which underwent a aza-Wittig reaction with phenyl ioscyanate to provide the carbodiimide 3. The latter intermediate reacted with alkylamines and regioselectively provided the 1,5-dihydro-pyrazolo[3,4-d]pyrimidin-4-one derivatives 5 and 6, some of which exhibited good fungicidal activity.     

LIGHT-MEDIATED CYCLIZATION OF (E)-3-(5-[6-HYDROXY-7-METHOXY] BENZOFURANYL)PROPENOIC ACID, A WATER-SOLUBLE PRECURSOR OF 8-METHOXYPSORALEN

The title compound is a stable, water-soluble "pro-drug" for 8-methoxypsoralen, which converts to psoralen upon photolysis with UVA light. The process involves the photolytic formation of a cis isomer that lactonizes in a dark reaction.     

A FACILE SYNTHESIS OF DIETHYL 1- ISOTHIOCYANO)ALKYLPHOSPHONATES[1]

Abstract

Novel, diethyl 1-(isothiocyano)alkylphosphonates 3 have been efficiently synthesized via a one-pot reaction of diethyl 1-azidoalkylphosphonates 1 with triphenylphosphine, followed by in situ transformation of thus formed phosphazenes 2 with carbon disulfide. Application of the title compounds in the synthesis of diethyl (N-phenylthioureido)- and (benzothiazol-2-ylamino)methylphosphonates was also described.     

CONVENIENT SYNTHESIS OF 2-(2-PHENYLETHYL)BENZOIC ACID: A KEY INTERMEDIATE IN THE SYNTHESIS OF DIBENZOSUBERONE

A convenient and improved synthesis of 2-(2-phenylethyl) benzoicacid, a key intermediate in the synthesis of dibenzosuberone is described.     

A new regioselective synthesis of 2,3,4,5-tetrahydro-6H-oxepino[3,2-c]pyran-6-ones,and [1]benzopyran-6-ones

Through an anti-Markovnikow hydration of some olefin derivatives of 4-hydroxy-2-pyrones, and 4-hydroxy-coumarins, followed by a regioselective intramolecular dehydration, involving the primary alcohols obtained and the enolic oxygen of the rings, promoted by Amberlyst 15 in boiling toluene, the new heterocycles 2,3,4,5-tetrahydro-6H-oxepino[3,2-c]pyran-6-one ( 3 ) and [1]benzopyran-6-ones ba,c were obtained in fair yields.     

2-[2,4-二羟基苯甲酰]苯甲酸金属盐的合成、表征及其光稳定能力研究

本工作合成了多种含不同过渡金属离子的络合物——2-[2,4-二羟基苯甲酰]苯甲酸钴、镍、锰金属盐.对它们进行了详细表征和光稳定能力进行了实际评价,结果表明这类化合物有很好的光稳定能力,并指出含锰离子的络合物具有最佳光稳定能力是由于锰离子对原有的分子内氢键结构破坏最小所致.     

SYNTHESIS OF ARYL(OR BENZYL)- (Z)-N-[2-AMINO-1,2-DICYANOVINYL]FORMAMIDINES

ABSTRACT

Starting from readily available ethyl(Z)-N-(2-amino-1,2-dicyanovinyl)formimidate (1), the N-aryl (or benzyl)-N′(-(2-amino-1,2-dicyanovinyl)formamidines (2) can be prepared in good yields by reaction with aromatic amines at room temperature in the presence of a catalytic amount of aniline hydrochloride.     

STUDY ON THE SYNTHESIS OF A NEW TYPE OF PHOSPHORUS HETEROCYCLIC COMPOUNDS-PYRAZOLO[3, 4-d]-1, 3, 2-DIAZAPHOSPHORIN-6-ONE

1-substituted-5-benzoylamino-4-pyrazolecarboxamides(2)were prepared by the reaction of 1-substituted pyrazolo[3, 4-d]-oxazinone(1)with amines in benzene.The compound 2 was refluxed with excess LiAlH₄ in a mixture of THF and ether, one of the two carbamoyl groups in the molecule 2 was reduced selectively.As the results, 1-substituted-5-benzylamino-4-pyrazolecarboxamides (3) were obtained.Compounds 3reacted with Cl₂PPh-X, or P(NET₂)3, producing the title compounds(4).The conditions of the reactions were studied.     

A SIMPLE METHOD FOR THE SYNTHESIS OF 2-AMINO-1-(4′-METHOXYPHENYL)-PROPANE

Synthesis of 2-amino-1-(4′-methoxyphenyl)-propane (II) starting from p-anisaldehyde (1) in 67% overall yield is described. Key reactions involved Horner–Wadswoth–Emmons olefination of 1 to form the ester 2 and Hoffmann degradation of amide 5 to obtain the amine II.     

旋光聚[乙烯-alt-R-N-(1-苯乙基)马来酰胺酸]的合成及静电自组装

以聚(乙烯-alt-马来酸酐)为原料,通过与R-(+)-α-苯乙胺的酰胺化反应,合成了一种新型的旋光聚电解质聚[乙烯-alt-R-N-(1-苯乙基)马来酰胺酸],利用红外吸收光谱、紫外吸收光谱、核磁共振氢谱和旋光度数据对其结构进行表征.聚[乙烯-alt-R-N-(1-苯乙基)马来酰胺酸]与聚二甲基二烯丙基氯化铵(PDDA)逐层静电自组装过程的紫外跟踪测试结果表明,带相反电荷的聚电解质间能够形成稳定增长的自组装膜,多层膜组装量随双层数指数增大.     

Die Synthese von 2,3,4,5-1H-Tetrahydroimidazo[2,1-b]chinazolin-2,5-dionen und analogen 2,3,4,5-1H-Tetrahydroimidazo[1,2-a]thieno[2,3-d] (bzw. [3,2-d])-pyrimidin-2,5-dionen

The Synthesis of 2,3,4,5-1H-Tetrahydroimidazo[2,1-b]quinazolin-2,5-diones and analogous 2,3,4,5-1H-Tetrahydroimidazo[1,2-a]thieno[2,3-d] (or [3,2-d])-pyrimidin-2,5-diones The syntheses of various imidazo [2, 1-b]quinazolinediones and their thiophene analogs are described.     

SYNTHESIS OF IMINO-C-DISACCHARIDES RELATED TO SUCROSE[1]

Stabilised ylides 1 and 10, prepared from perbenzylated and peracetylated allyl C-glucopyranosides, respectively, were reacted with differently protected D-serinal; osmylation of the obtained α,β-unsaturated ketones 3 and 12, followed by intramolecular reductive amination, afforded different imino-C-disaccharides 14, 15, 18, and 19 related to sucrose.     

SOME REACTIONS OF 3-AMINO-2-CARBOETHOXY-4,6-DIMETHYLTHIENO[2,3-b]-PYRIDINE. SYNTHESIS OF SOME NEW THIENOPYRIDOPYRIMIDINES

Abstract

Thienopyridine oxazinone (1) has been prepared and explored as a precursor by its reaction with some reagents namely, ammonium acetate, aliphatic amines, aromatic amines, hydrazine hydrate, thiosemicarbazide, and ethyl glycinate to give pyridothienopyrimidines (11-VII). The pyrimidinone compound (11) was converted to the 4-chloro derivative (X) by its reaction with excess POCl₃ Interaction of the 4-chlorocompound (X) with some reagents namely, hydrazine hydrate, methyl amine, aniline, sodium thiophenolate, ethyl glycinate, thiosemicarbazide and thiourea, yielded pyridothieno-pyrimidine derivatives (XI-XVII) substituted at 4-position, respectively.     

A SONOCHEMICAL PROTOCOL FOR THE SYNTHESIS OF PERMODIFIED CYCLODEXTRINS[1]

A series of O-peralkylated β- and γ-cyclodextrins, commonly used as stationary phases in high-resolution gas chromatography or as drug carriers, has been prepared both according to the usual methods and with sonocatalysis. The sonochemical protocol, using either a common cleaning bath or sonochemical apparatus, resulted in markedly improved yields, reaction times and reproducibility.     

SYNTHESIS OF 3-BENZYL-GLYCERIC ACID:A KEY INTERMEDIATE OF A NOVEL CYCLIC ESTER MONOMER

A route was proposed to synthesize 3-benryl-glyceric acid (3-BGA) as an important intermediate for the synthesis ofa novel six-membered cyclic ester monomer - 3-benzyloxymethyl-1,4-dioxane-2,5-dione (3-BMG). According to this route,3-BGA was obtained from ring-opening reaction of benzyl alcohol with methyl glycidate, which was prepared from theepoxidation of methyl acrylate using sodium hypochlorite as the oxidant.