A FACILE SYNTHESIS OF HETEROCYCLE SUBSTITUTED CHALCONE AND 5-NITROFURANYL OLEFIN DERIVATIVES

Reaction of heterocycle substituted telluronium salts with aroma- tic aldehydes under mild conditions gave corresponding chalcones.In the presence of dibutyl telluride,2-bromomethyl-5-nitrofuran condensed easily with aromatic aldehydes in THF to afford corresponding olefin derivatives as one-pot reaction.

Synthesis of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives

A series of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives have been synthesized by utilizing the coupling of methyl 3- methoxy-4hydroxy-5-bromocinnamate with cuprous phenylacetylide as the key step. The structures of the new compounds were confirmed by 1H NMR, IR and MS. The structure of compound 14 was further confirmed by single crystal X-ray. Compound 17 showed cytotoxic activity against human lung carcinoma A549.

PHOTOINDUCED ADDITION REACTIONS OF CHLORANIL WITH FURAN DERIVATIVES

Photoinduoed reaction of chloranil (TCBQ) with 2-methylfuran la and 2,5-dimethylfuran 1b in benzene gave addition products 2a and 2b respecvely together with tetrachlorohydroquinone 3. A mechanism of sequential electron and proton transfer from la or 1b to ~3TCBQ followed by coupling of the furfuryl and semiquinone radical pairs was proposed and is evidenced by the photo-CIDNP studies of the TCBQ-1a and TCBQ-1b systems.

Asymmetric Synthesis and Crystal Structure of a Bioactive Morpholine Derivative

A novel morpholine derivative was synthesized by Michael addition/internal nucleophilic substitution of 4-（L）-menthyloxy（1R,2S,5R）-butenolide with phenyl-glyalcohol under mild condition, and its structure was determined by X-ray diffraction. The target compound belongs to orthorhombic, space group P212121 with a = 5.7729（7）, b = 11.5032（14）, c = 25.161（3）A, Mr = 319.35, Z = 4, V = 1670.8（4）A^3, Dc = 1.270 g/cm3, μ（MoKα） = 0.094 mm^-1, F（000） = 680, Flack = 0.01（2）, R = 0.0398 and wR = 0.0914.

Hydrothermal Synthesis,Structure and Characterization of a New 2D Co(Ⅱ) Coordination Polymer Based on Flexible Double Imidazole Derivative and Oxalate

A 1D supramolecular compound [dmbbbi]（1） and a 2D cobalt coordination polymer [Co（dmbbbi）（ox）] 2（2） [dmbbbi=1,1-（1,4-butanediyl）bis（5,6-dimethylbenzimidazole）,ox=oxalate],C48H52Co2N8O8,were obtained under hydrothermal conditions by tuning the molar ratio of the reactants.The crystal structure analysis reveals that in compound 1,the adjacent dmbbbi molecules connect with each other via hydrogen bonds to form a 1D supramolecular chain.In compound 2,two crystallographically independent Co2＋ ions show the same six-coordination mode.Each Co2＋ ion is coordinated by four oxygen atoms from two ox anions and two nitrogen atoms from two cis-dmbbbi ligands.The adjacent Co2＋ ions are bridged by ox anions to generate an infinite 1D zigzag chain,which is extended by pairs of dmbbbi ligands to form a 2D honeycomb-like（6,3） network.Moreover,the thermal stability and the electrochemical property of compound 2 were studied.

Furan Derivatives and Polyketides from the Fungus Irpex lacteus

Eight new furan derivatives,irpexins A‒H(1‒8),two new polyketides,irpexins I and J(9 and 10),together with nine known compounds were isolated from the fermentation of Irpex lacteus.The structures and absolute configurations were elucidated on the basis of extensive spectroscopic methods and Mosher ester reaction.All compounds shows no cytotoxicity to human MCF-7 and Hela cancer cell lines at the concentration of 10μM.

STUDIES ON THE SYNTHESIS AND BIOLOGICAL ACTIVITY OF 1-ARYLOXYACETYL-4-AROYLTHIOSEMICARBAZIDE DERIVATIVES

A series of new 1-aryloxyacetyl-4-aroylthiosemicarbazides were synthesized by means of solid-liguid phase transfer catalysis. The promoting effects of these new compounds on wheat growth were observed.

Practical synthesis allenyl and homopropargyl alcohol through Cp_2TiCl_2 -Mg with propargyl alcohol derivatives

Reaction of Cp2TiCl2-Mg synthetic equivalent of practical Ti(II) reagent with propargyl alcohol derivatives affords allenyl titanium compounds in good yields.thus, providing an efficient and practical methods for synthesis of both allenyl and homopropargyl alcohols by the successive treatment with aldehydes and ketones.

Homogeneous Synthesis and Characterization of Quaternized Cellulose Derivatives in NaOH-urea Aqueous Solutions

Quaternized cellulose( QC) derivatives were synthesized by reacting cellulose with 3-chloro-2-hydroxypropyl trimethyl ammonium chloride( CHPTAC) in an aqueous solution of Na OH-urea. The chemical structures and physical properties of the obtained QC derivatives were characterized using nitrogen content analysis,Fourier transform infrared spectroscopy( FT-IR),~1H-nuclear magnetic resonance(1H-NMR),X-ray diffraction( XRD),and thermal gravity analysis( TGA). The FT-IR and ~1H-NMR results confirmed the successful introduction of cationic quaternary ammonium groups into the main chain of cellulose. A series of QC derivatives with the degree of substitution( DS) values ranging from 0. 33 to 0. 80 were derived by adjusting the molar ratio of CHPTAC to anhydroglucose unit( AGU) of cellulose,concentration of cellulose in the Na OH-urea solution,as well as reaction temperature and time. According to the DS values of the QC derivatives,the optimized synthetic conditions were as follows: 25℃ reaction temperature,3% cellulose in Na OH-urea solution,the molar ratio of etherification agent to glycosidic cellulose of 15∶ 1,and 12 h reaction time. The TGA and XRD results revealed that the crystalline structure was destroyed during etherification,and the thermal stability of the QC derivatives was lower than that of cellulose.

Enzymatic Synthesis of a CCK-8 Tripeptide Derivative

The enzymatic synthesis of CCK-8 tripeptide derivative Phac-Met-Asp(OMe)-Phe-NH2 is reported. Starting with Phac-Met-OCam, we have successfully synthesized the target tripeptide with three free or immobilized enzymes, ?chymotrypsin, papain and thermolysin in reasonable yields. The key steps in this synthesis were the coupling of Phac-Met-OCam and H-Asp(OMe)2 to form Met-Asp peptide bond catalyzed by ?chymotrypsin and the selective hydrolysis of -ester of Phac-Met-Asp(OMe)2 catalyzed by papain.

Extrapolation of the gold-catalyzed cycloisomerization to the palladium-catalyzed cross-coupling/cycloisomerization of acetylenic alcohols for the synthesis of polysubstituted furans:Scope and application to tandem processes

This paper describes the development of an integrated approach for the preparation of diverse furan derivatives from acetylenic alcohols by gold and palladium catalyzed π-activation chemistry.Notably,this new method was found to be amenable to cyclooctyl-containing substrates,which represents a significant extension to this methodology compared with our previous reports.Furthermore,this newly developed method allowed for the direct construction of cyclooctyl furans from their synthetic precursors under Sonogashira conditions.Experimental results revealed that palladium played two major functions in these reactions,including（1） an essential catalyst in the cross-coupling reaction of the substrates;and（2）facilitating the cyclization of the acetylenic alcohol intermediates through a typical π-activation process.The scope of this chemistry was highlighted by the one-pot synthesis of 3-iodofuran,which provided an opportunity for further functionalization（via coupling methods）.Finally,the AuBr3 protocol was also elaborated to domino cyclization/C-H activation reactions,as well as the cyclization of acyclic precursors.Taken together,the results of this study demonstrate that gold and palladium catalysts can be used to complement each other in cyclization reactions.

AN EFFICIENT SYNTHESIS OF α-(BENZOTHIAZOL-2-YLOXY)PHOSPHONATES DERIVATIVES

Fifteen title compounds 3a-0 were synthesized by condensation of 2chloro-benzothiazole with a-hydroxyphosphonates in good yields us- ing potassium iodide/tetrabutyl ammonium bromide as catalyst.All new com- pounds have been identified by ~1H-NMR,IR and elemental analysis.

A CONVENIENT SYNTHESIS OF 8-ALKYL S'-ALKYL (ARYL) DITHIOPHOSPHORIC ACID DERIVATIVES

The chlorination of S-alkyl(aryl) 0,0-dialkyl dithiophosphates with phosphorus oxychloride proceeds with isomerization to give S-alkyl S'-alkyl(aryl) dithiophosphorochtoridates, which react further with various nucleophiles in the presence of base to give the title compounds

Studies on the synthesis and antifungal activity of thiochromanone derivatives

In this paper nine New Mannich bases of 6-fluoro-thiochromanone and eight new 3-substituted-6.8-dichloro thiochromanones were synthesized and their structures were confirmed by IR, H-1-NMR and elementary analysis. Most of these compounds showed excellent antifungal activity.

NEW METHOD OF SYNTHESIS OF 1-OXO-3-ACETONYL-DIHYDROBENZO(C)FURAN

o-Carboxybenzaldehyde (1)and acetone gave the Claisen-Schmidt condensation product, which readily cyclizes on acidification to give 1-oxo-3-acetonyl-dihydrobenzo [c]furan(4)in 68% yield. Other methyl ketones behaved similarly.

A CONVENIENT SYNTHESIS OF CYCLOOCTANE DERIVATIVES

1,5-Bismethylene cyclooctane derivatives were synthesized by the palladium catalyzed annulation reaction of 2-methylene propane-1,3-diol diacetate with compounds containing active methylene groups in the presence of BSA.