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1.
Propyl O-(α-L-rhamncpyranosyl)-(1→3)-[2,4-di-O-(2s-methylbutyryl)-α-L-rham-nopyranosyl]-(1→2)-(3-O-acetyl-β-D-glucopyranosyl)-(1→2)-β-D-fucopyranoside (1), the tetrasac-charide moiety of Tricolorin A, was synthesized in total 23 steps with a longest linear sequence of 10 steps, and overall yield of 3.7% from D-Glucose. The isomerization of the dioxolane-type berzyli-dene in the presence of NIS/AgOTf was observed. Tetrasaccharide 1 exhibited no activity against the cultured P388 cell as Tricolorin A did.  相似文献   

2.
李红韦堃  吴养洁 《中国化学》2007,25(11):1704-1709
A variety of 2-arylnaphtho[ 1,2-d]oxazole derivatives were efficiently synthesized in moderate to high yields by the reaction of aromatic aldehydes with 1-amino-2-naphthol derivatives in the presence of triethylamine in refluxing ethanol in air. Seven new 2-arylnaphtho[1,2-d]oxazole derivatives were obtained and characterized by the spectral data and elemental analysis. In addition, the X-ray crystal structures of 2-[4-(N,N-dimethylamino)phenyl]naphtho[ 1,2-d] oxzole (3d) and 1, 1'-bis(naphtho[ 1,2-d]oxazol-2-yl)ferrocene (3n) have been determined.  相似文献   

3.
A convenient synthetic pathway to 2-aryl-5,6-dihydro-4H-benzo[f][1,2,4]triazolo[1,5-α]azepine derivatives 7 was developed. The synthesis was based on the cycloaddition of the 1,2,3,4-tetrahydronaphthalene a-acetoxy azo compounds 3 with Ar-CN in the presence of AlCl3 and the consecutive ring enlargement.  相似文献   

4.
程琳  应磊  杨小玲  蹇锡高 《中国化学》2005,23(2):200-203
A new monomer diacid, 1,2-dihydro-2-(4-carboxylphenyl)-4-[4-(4-carboxylphenoxy)-3-methylphenyl]phtha-lazin-1-one (3), was synthesized through the aromatic nucleophilic substitution reaction of a readily available unsymmetrical phthalazinone 1 bisphenol-like with p-chlorobenzonitrile in the presence of potassium carbonate in N,N-dimethylacetamide and alkaline hydrolysis. The diacid could be directly polymerized with various aromatic diamines 4a-4e using triphenyl phosphite and pyridine as condensing agents to give five new aromatic poly(ether amide)s 5a-5e containing the kink non-coplanar heterocyclic units with inherent viscosities of 1.30-1.54 dL/g.The polymers were readily soluble in a variety of solvents such as N,N-dimethylformamide (DMF), N,N-dimethyl-acetamide (DMA), dimethylsulfoxide (DMSO), N-methyl-2-pyrrolidinone (NMP), and even in m-cresol and pyridine (Py). The transparent, flexible and tough films could be formed by solution casting. The glass transition tem-peratures Tg were in the range of 286-317℃.  相似文献   

5.
2H-1,2,3-Diazaphospholes 3a-3h were prepared from various ketone acylhydrazones and phosphorus trichloride in the presence of triethylamine. Compounds 3 underwent feasible hetero-Diels-Alder reactions with cyclopentadiene to afford the respective anellated [1,2,3]diazaphospholes 4a--4d as well as 4a‘--4d‘ in moderate yields. The endo rule in the reaction was observed under kinetic control conditions.  相似文献   

6.
With phosphoric formic acid (PFA) and its analog,phosphonoacetic acid (PAA),as the lead compounds,α-amino phosphonates were introduced into PFA and PAA.The derivatives oi N-( alkoxycarbonyl-aikoxyphosphonyl)-α-arnino phosphonates (Ⅰ) and N-(alkoxycarbonyl-methyt-alkoxyphosphonyl)-α-amino phosphonates (Ⅱ) with the N-terminal of amino phosphonates bonding to phosphorus atom of PFA and PAA were synthesized via the reaction of the corresponding phosphonyl chloride with a-amino phosphonates in the presence of a base.The 31P NMK spectra of Ⅰ and Ⅱwere determined.It is found that the coupling constants 3Jpp with R3 being alkyl group were lower than those with R3 being (substituted) phenyl,and this result was discussed.The preliminary bioassay showed that some of the compounds Ⅰ and Ⅱhave better activities against tobacco mosaic virus (TMV).The inhibitory was higher than that of DHT (2,4-dioxyhexahydro-1,3,5-triazine).In addition,some of the compounds showed the activity against cancer cells.  相似文献   

7.
Functional monomer (MP)_2PT having tertiary aromatic amino group was systhesized from the reaction of N, N-di (2-hydroxypropyl)-p-toluidine with 2-methyl acryloyl chloride. In the presence of organic peroxide, the radical polymerization of (MP)_2PT in toluene took place. The kinetics of (MP)_2PT polymerization and the ESR spectra of LPO-(MP)2PT-MNP systems were determined respectively.  相似文献   

8.
α-{3-[2-hydroxy-3-(N-methyl-N-hydroxyethylamino)propoxy]propyl}-ω-butylpolydimethylsiloxanes Ⅲ with various moleculax weights were prepared by epoxy addition of α-[3-(2,3-epoxy-propoxy)propyl]-ω-butylpolydimethylsiloxanes Ⅱ and Nmethylmonoethanolamine.At each step.the outcome compounds were characterized through FT-IR and NMR spectra,the results showed that each step was successfully carried out and objective products were achieved.  相似文献   

9.
Chromone-2-carboxylates are widely used for the pharmacological activity of several of its derivatives1. The general synthesis of such chromone derivates includes two steps (Scheme 1): a Claison condensation of dialkyl oxalate with 2-hydroxyacetophenones to achieve alkyl 3-(2-hydroxyphenyl)-3-oxopropanoates in the presence of NaH, NaOEt, or NaOMe; cyclodehydration of the alkyl 3-(2-hydroxyaryl)-3-oxopropanoates to obtain chromones under acid condition. The total yield of the two steps is q…  相似文献   

10.
Thermoanalysis study has been carried out on the complex of bis[1-(2-thienyl)-4,4,4-trifluoro-butanedione- 1,3]copper(Ⅱ) and its adducts with pyridine, 2,2′-bipyridine, quinoline and dimethyl sulfoxide in a dynamic ni-trogen atmosphere by simultaneous TG-DTG-DSC technique. The experimental results showed that the decomposi-tion modes of the solvent molecules were various according to the different structures of the complex, in general, the decomposition of them was ahead of the decomposition of the ligand 1-(2-thienyl)-4,4,4-triflurobu- tanedione-1,3. Among them the adduct with 2,2-bipyridine showed a quite unique thermal behavior. Several methods have been jointly used to study the kinetics of all the thermal decomposition stages for title compounds, which showed that the evolution of the solvent molecules was controlled mainly by Rn mechanism (or Am mechanism for 2,2-bipyridine adduct) with lower activation energy; while the release of 1-(2-thienyl)-4,4,4-trifluro-butane- dione-1,3 was gove- rned by D2 or D3 mode with higher activation energy.  相似文献   

11.
The title compound[Zn(btzb)2Cl2]·2H2O(1·2H2O,btzb=1,2-bis(5-tetrazolyl)benzene)was synthesized in situ by the[2 3] cycloaddition reaction of phthalonitrile with NaN3 in water in the presence of ZnCl2 under refluxing conditions.1·2H2O crystallizes in the monoclinic system,space group P21/c with a=9.0119(18),b=7.5566(15),c=18.076(5)(A),β=114.67(2)°,V=1118.6(4)(A)3,Z=2,Dc=1.784 g/cm3 T=223(2)K,C16H16N16O2Cl2Zn,Mr=600.74,F(000)=608,μ(MoKα)=1.393 mm-1,S=1.081,R=0.0306 and wR=0.0669 for 1896 observed reflections with Ⅰ >2σ(Ⅰ).The Zn2 ion of 1 is coordinated by four N atoms from two btzb ligands and two Cl atoms,forming a distorted octahedral coordination geometry.A number of intermolecular hydrogen bonding interactions between molecules 1 and/or the solvated water molecules result in a 3D hydrogen-bonded structure.The luminescent property of 1·2H2O was also investigated.  相似文献   

12.
In this paper , 10 novel 6-aryl-3-(5'-phenyl-2H-tetrazole-2'-methylene)-S-triazolo[3, 4-b]-1,3,4-thiadiazoles have been synthesized by the condensation of 3-(5'-phenyl-2H-tetrazole-2'-methylene)-4-amino-5-mercapto-1,2,4-triazole with various aromatic carboxylic acids in the presence of phosphorus oxychloride. The structure of these compounds was determined by elemental analysis , UV, IR, 1H NMR and MS. Their spectral properties were also discussed.  相似文献   

13.
The compound phenol,2-[4(S)-4,5-dihydro-4-phenyl-2-ozazolinyl(1,C15H13NO2) was synthesized with a simple,one step method free of water and air.It was obtained in a moderate yield from the reaction of 2-hydroxybenzonitrile with optically active amino alcohol in chloroben-zene under dry,anaerobic conditions.It belongs to the orthorhombic system,space group P212121 with a = 5.786(5),b = 10.730(5),c = 19.722(5),C15H13NO2,Mr = 239.26,V = 1224.4(12)3,Z = 4 and Dc = 1.298 mg/m3.The final R = 0.0324 for 1627 observed reflections with Ⅰ 2σ(Ⅰ) and Rw = 0.0826 for all data.The structure of compound 1 was determined by X-ray diffraction,NMR and HRMS.  相似文献   

14.
李响赵刚  曹卫国 《中国化学》2006,24(10):1402-1405
Asymmetric reduction of diketones with borane reagents generated in situ using cheap and available NaBH_4 andSnCl_2 in the presence of(S)-(-)-α,α-diphenyl-2-pyrrolidinemethanol was successfully achieved to yield the corre-sponding chiral diols with excellent stereoselectivity and enantioselectivity.And the chiral diol was transformedinto optically pure C_2-symmetricl chiral amine or thioether.  相似文献   

15.
The effect of cationic micelles of cetyltrimethylammonium bromide (CTAB) on the interaction of chromium dipeptide complex ([Cr(Ⅲ)-Gly-Gly]2 ) with ninhydrin under varying conditions has been investigated. The rates of the reaction were determined in both water and surfactant micelles in the absence and presence of various organic and inorganic salts at 70 ℃ and pH 5.0. The reaction followed first- and fractional-order kinetics with respect to [Cr(Ⅲ)- Gly-Gly2 ] and [ninhydrin]. Increase in the total concentration of CTAB from 0 to 40×10-3 mol·dm-3 resulted in an increase in the pseudo-first-order rate constant (kψ) by a factor of ca 3. Quantitative kinetic analysis of kψ-[CTAB] data was performed on the basis of the pseudo-phase model of the micelles. As added salts induce structural changes in micellar systems that may modify the substrate-surfactant interactions, the effect of some inorganic (NaBr, NaCl, Na2SO4) and organic (NaBenz, NaSal, NaTos) salts on the rate was also explored. It was found that the tightly bound counterions (derived from organic salts) were the most effective.  相似文献   

16.
郑卫红  袁承业 《中国化学》2006,24(9):1170-1174
Reaction of diethyl 2,2-difluoro-3-(a-methylbenzyl)imino-4,4,4-trifluoropropanephosphonate (3) with triethylamine afforded a mixture of normal [1,3]-proton shift reaction product 5 and its HF-eliminated compound 6Z in 1 : 1 ratio. Upon hydrolysis, this reaction mixture gave solely 1,3,3,3-tetrafluoro-2-dioxypropanephosphonate (9). Reaction of 3 with DBU provided only 6, in which the ratio of E/Z forms was dependent on the reaction conditions. Aqueous hydrolysis of 6 led to 9. Catalytic hydrogenation and hydrogenolysis of 6 gave geometric isomers of 11 as expected. The reaction mechanism involved was discussed.  相似文献   

17.
王义  秦茜  桑瑞利  徐立 《结构化学》2014,33(7):995-1000
A new complex K0.5[K(18-crown-6)]1.5Ge9·1.5en(1) which contains unprecedented "up" and "down" chain arrangement of unit [-(Ge-9-K-Ge9)3-] has been prepared by the reaction of K4Ge9 with HgS in ethylenediamine(en) in the presence of 18-crown-6(1,4,7,10,13,16-hexaoxacyclooctadecane), and characterized by X-ray structure analysis. The color of the title crystals(black), which is darker than that of the reported three compounds with chains of germanium clusters, may result from the naked K+ and their interactions with the chain. And the structure differences between 1 and the reported three compounds with chains of germanium have also been discussed.  相似文献   

18.
5,6-Dihydrothieno[3′,2′:4,5]thieno[2,3-d]pyrimidin-4(3H)-ones 6 were synthesized in yields of 71-87%by a consecutive method,which includes aza-Wittig reaction of iminophosphorane 3 with aromatic isocynate to give carbodiimide 4 and subsequent reaction of 4 with various amines,phenols or alcohols in the presence of catalytic amount of sodium ethoxide or solid potassium carbonate.  相似文献   

19.
1 INTRODUCTION The design, development and marketing of new chiral drugs are now a major theme in the drug chirality research and industry[1]. In 1996, the FDA announced it would consider further incentives for developing single isomer drugs because of their bet- ter pharmacokinetics prosperity, safety, and tolera- bility. Our recent drug candidate, 9α-(3-azabicyclo- [3,3,1]nonanyl)-2?-cyclopentyl-2?-hydroxyl-2?-thien- ylacetate I, is a potential selective M1 antagonist. It is composed…  相似文献   

20.
N-(methoxycarbonyl-methoxyphosphonyl)-α-amino add esters (I) were synthesized via the reaction of the corresponding phosphonyl chloride with amino acid ester hydrochlorides in the presence of a base. Compound I was aminated to yield N-(isopropylcarbainoyl-methoxyphosphonyl)-α-amino acid esters (II). With l-amino acids as starting materials, the isomers of products I and II were separated and their configurations were confirmed by the single crystal X-ray diffraction of II.  相似文献   

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