STUDIES ON SYNTHESIS OF SUGAR NUCLEOTIDES

Glucosyl phosphotriester of adenosine and glucosyl thiophosphotriester of adenosine were synthesized by phosphite-triester methodology.     

SYNTHESIS OF A NEW TYPE OF SCOPOLAMINE ANALOGUES

A series of compounds,which are structurally analogous to scopolamine and also inaccordance with the general formula of neuroleptic benzamides,were synthesized and tested fortheir potential antipsychotic activity.     

SYNTHESIS OF AZA-CROWN-ETHER CHOLESTERIC LIQUID CRYSTALS

Five aza-crown-ethers were synthesized and four of them shown to have cholesteric liquid crystalline properties. Their properties relevant to cholesteric liquid crystal were determined by DSC and the textures. The type of cholesteric mesomorphic azacrown ether have not been reported so far.     

SYNTHESIS AND PROPERTIES OF NEW INTERPOLYMERIC COMPLEXES

β-(2-imidazolinyl)-ethyl methyl diethoxy silane quarternary halides and its condensed polymers with bisphenol A were synthesized and characterized. The polycation-polyanion complexes were prepared by the condensed polymers and poly (styrene sulfonate). The solubility and thermal stability of interpolymeric complexes were investigated.     

SYNTHESIS OF POLYMER—SUPPORTED PALLADIUM CATALYSTS AND THEIR CATALYTIC BEHAVIOR FOR THE SELECTIVE HYDROGENATION OF MESITYL OXIDE

Copolymer of styrene-divinylbenzene in bead from was made by suspension polymerization.After chloromethylation and amination,five kinds of polymeric amines were thus obtained.These polymers were reacted with palladium chloride,and were then reduced.The polymer-supported catalysts synthesized above were used to catalyze the selective hydrogenation of mesityl oxide under reaction conditions of 80℃ and 10kg/cm^2,using methanol as a solvent.The catalytic activity and MIBK(methyl isobutyl ketone) formation selectivity of the catalysts were examined.     

SYNTHESIS OF A NEW KIND OF AMPHIPHILIC COPOLYMER AND CHARACTERIZATION OF THEIR LB FILMS

A new kind of amphiphilic copolymer was synthesized with azo bond functional side chains, and elementary studies about formation of I,B film, UV-visible spectra and photoelectrical properties of multilayers of this kind of amphiphilic copolymer were reported.     

SYNTHESIS OF A-TYPE MOLECULAR SIEVEFROM RECTORITE

A-type molecular sieve was synthesized from natural rectorite viawater-floatation, deferrization and hydrothermal process. X-ray diffraction andthe determination of the adsorption suggest that the obtained molecular sieve hasgood crystalline and adsorptive performance. The crystallization mechanismwas investigated. The variations in the basicity of the liquid components, thegrain size and Si/Al ratio during the crystallization were studied.     

SYNTHESIS AND CHARACTERIZATION OF DVE-CO-MA DERIVATIVES OF CIS- PLATINUM COMPLEXES

Copolymer of divinyl ether and maleic anhydride (DVE-co-MA) derivatives of cis-platinum complexes were synthesized and characterized by elementary analysis, IR and XPS ( X-ray photoelectron spectroscopy). The behavior of the products in biological environment was also studied. UV-visible and fluorescence spectra show that these polymer derivatives are able to exchange ligands with selected nucleophilic groups in biological environment.     

SUSPENSION-SWELLING GRAFT COPOLYMERIZATION——SYNTHESIS OF ACS RESINS*

Acrylonitrile (AN)-chlorinated polyethylene (CPE)-styrene (St) (ACS) terpolymer was synthesized by suspension-swelling graft copolymerization method, in which two key factors such as dispersing system and time were studied. Highly effective comples dispersing system was chosen and determined, and two-layer protection model was put forward to clarify the stable effect mechanism Varying the swelling time of CPE in AN and St monomer mixture, some results such as grafting effect, particle characteristics, rubber particle morphology and its size distribution, and properties of ACS resins were investigated , thus the optimum swelling time was proposed.     

SYNTHESIS AND CHARACTERIZATION OF SOME THERMOTROPIC LIQUID CRYSTALLINE POLYAMIDES

A series of novel mesogenic polyamides containing a flexible pendent side group wassynthesized by solution condensation polymerization. The new monomers, diacids and di-amines containing flexible elements of diferent lengths, were also synthesized and character-ized by ~1HNMR, mass spectroscopy and elemental analysis. The polymers were character-ized by viscosity measurements, differential scanning calorimetry (DSC), X-ray diffiactionand polarizing optical microscopy These studies revealed that polyamides containingflexible elements of a sufficient length exhibited thermotropic liquid crystalline(LC) pro-perties. The melting temperatures of this series of polymers were particularly sensitive tothe length of the flexible segment on the main chain and that of the flexible pendent esterside chain. Lyotropic LC behaviours were also observed in solution.     

SYNTHESIS AND CHARACTERISTIC OF POLYSILANES CONTAINING Si-H BOND

Three kinds of polysilanes containing Si-H bond,■■ CH_3SiCH_3■_x■CH_3SiH■_y■_n and■PhSiPh■_π■CH_3SiH■_y■CH_3SiCH_3■, have been synthesized. The structures of these copolymers were investigated by IR, ~1H-NMR and ~(13)C-NMR and their molecular weights were measured.     

SYNTHESIS OF LIQUID CRYSTALLINE POLYACRYLATES WITH THIOESTER AS BRIDGE-BOND

A new series of acrylates with the same mesogens containing thioester as bridge-bondwere synthesized, and the acrylates were characterized by H~1 NMR, IR and MS. Thepolymers were obtained by radical polymerization using AIBN as initiator. The monomersand polymers exhibit thermotropic-enantiotropic liquid crystalline behavior.     

SYNTHESIS AND ANTITUMOR ACTIVITY OF PEPTIDYL-N~2-HYDROXYMETHYL-5-FLUOROURACIL

Six hydrophobic peptidyl and four amino acid (L-Val, L-Leu,L-Phe, L-Gly) derivatives of 5-fluorouracil(5-FU) were synthesized.The structure of these compounds were characterized by ~1H-NMR, IR,UV spectra and elemental analysis. The antitumor activity was test-ed against EAC cells in vitro.     

SYNTHESIS AND POLYMERIZATION OF 2-OXO-3-METHYLENE-1,4-DIOXANES

A new kind of monomers was successfully synthesized by the reaction between 2-chloro methyl cycloketal and trimethylsilyl cyanide, followed by ring closure and dehaiogenation. Polymerizations of the monomers were carried out in benzene solution at 80℃with benzoyl peroxide as initiator. Both the structures of monomers and polymers were characterized by IR, ~1H NMR, ~(13)C NMR and elemental analysis.     

SOLID-PHASE SYNTHESIS OF 2''''—5'''' OLIGOADENYLATE——2''''—5''''A CORE

With phosphotriester approach, the 2'—5' linked oligonucleotide——2'—5'A core was synthesized by using cross-linked polyacrylmorpholide resin as the support and the mesitylene sulfonyl chloride and N-methylimidazole as the condensing agent. Synthesizing the 2'—5'A core with this method has not yet been described. The yields that each of the protected monomers was attached to the polymeric support were satisfactory, i.e., 100%, 60% and 91% respectively.For the synthesis, we improved the methods for preparing the polymeric support and a series of intermediates. For this reason, the yields of the products were markedly increased and the operations to separate the products from the by-products and reagents were simplified.     

TOTAL SYNTHESIS OF YEAST ALANINE TRANSFER RIBONUCLEIC ACID

By a combination of chemical and enzymatic methods, small oligonucleotides with lengths varying from 2 to 8 nucleotides were synthesized from mononucleotides. The small oligonucleotides were then ligated with T_4 RNA ligase into six laxge ligonucleotides (9 to 19 nucleotides long) which were further ligated to form two half molecules with 35 and 41 nucleotides respectively, Finally, the two synthetic half molecules were annealed and ligated to obtain the whole molecule of yeast alanine tRNA (tRNA_y~(Ala)). Prior to this, two semi-syntheses were performed, i. e. ligation of the synthetic 5'-half molecule with the natural 3'-half molecule and that of the natural 5'-half molecule with the synthetic 3'-half molecule.     

SYNTHESIS OF POLYSILOXANE-SUPPORTED SELENAETHER PLATINUM COMPLEX AND ITS CATALYTIC PROPERTY FOR HYDROSILYLATION OF OLEFINS

A new type of selenious polymer, silica-bound polybispropoxyethyl-selenidesilsesquioxane,and its platinum complex were synthesized from bis-allyloxyethyl selenide via hydrosily-lation with triethoxysilane, followed by immobilized on fumed silica, and then reactingwith potassium chloroplatinite under nitrogen atmosphere in acetone. It was found thatthe platinum complex can catalyze the hydrosilylation of olefins with triethoxysilane effec-tively The effects of the nature of the substrate, the amount of complex used, and thereaction temperature on the catalytic activity were investigated.     

CHEMOTHERAPEUTIC POLYMERS. THE SYNTHESIS OF POLYMERS CONTAINING 5-FLUOROURACIL IN THE MAIN CHAIN

1,3-Dialkyl-5-fluorouracil compounds and polymers containing 5-fluorouracil in the main chain were synthesized by the reaction of 5-fluorouracil with alkylbromidcs and polymethylene bromides respectively. The structures of the new compounds and polymers were confirmed by IR and NMR spectra as well as elemental analyses.The factors affecting the polycondensation, such as the temperature and time of the reaction were investigated. The anti-tumor activity of some of the 5-fluorouracil containing compounds and polymers were also measured.     

SYNTHESIS OF 4,6-DISUBSTITUTED 5-THIOXO-1,2,4-TRIAZIN-3-ONE FROM BENZOTHIOFORMANILIDE

A method of synthesis of 4,6-disubstituted 5-thioxo-1,2,4-triazin-3-ones from benzothioformanilides and semicarbazide is described.And six newcompounds were synthesized by this method.     

SYNTHESIS OF N,N''''-DISUBSTITUTED MONOTHIOXAMIDE AND STUDY OF THEIR REACTIONS WITH DIAMINES

In this paper, six N,N'-disubstituted aonothioxamides were synthesized and the reactions between these monothioxamines and diamines (1,2-diamino ethane and 1,3-diamino propane) were studied. Some new compounds were synthesized by using these reactions.