SYNTHESIS OF ACYCLIC ANALOGS OF BENZOTRIAZOLE AND INDOLE NUCLEOSIDE CONTAINING PERFLUOROALKYL GROUP

1-[(2-hydroxyethoxy)methyl]benzotriazole and -indole containing perfluoroalkyl group have been synthesized.

Synthesis of Phenylpropanoid Glycoside Analogs

The regioselective acylation of unprotected phenylethyl glucoside withcinnamoyl chloride leads to 6-OH cin-namoylated glucoside. In this manner, thirteen phenylpropanoidglycoside analogs were designed and prepared. Their structure was confirmed by ~1H NMR and ^(13)CNMR spectra.

Studies on the Synthesis of a Natural Product-Piceatannol and its Analogs

Piceatannol, (E)-3, 3, 4, 5-tetrahydroxy stilbene, a natural polyhydroxy stilbene, possesses many biological activities, its synthesis has been reported. We designed another route of its synthesis, which can be controlled more easily. The synthetic product was characterized by elemental analysis, IR, MS and 1H-NMR. Its analogs were synthesized by the similar method.

Studies on the Synthesis of Pyridine Analogs of the Natural Product3,5,4'-Trimethoxystilbene

Five pyridine analogs of the natural product, 3, 5, 4'-trimethoxystilbene, were synthesized. The final compounds were characterized by 1H-NMR.

Synthesis and antibacterial activity of 4″-O-carbamoyl analogs of clarithromycin

A series of novel 4'-O-carbamoyl analogs of clarithromycin were synthesized and evaluated for their in vitro antibacterial activity. All of the desired compounds showed excellent activity against erythromycin-susceptible S.pneumoniae.Particularly,4-fluorobenzyl carbamate 7a demonstrated potent activity against erythromycin-resistant S.pneumoniae encoded by the mef gene,and remarkably improved activity against erythromycin-resistant S.pneumoniae encoded by the erm gene,and the erm and mef genes.

Synthesis and Antibacterial Activity of Novel Oxazolidinone Analogs Containing Substituted Thiazole/Fused-Bicyclic Groups

Sixteen novel oxazolidinone analogs containing substituted thiazole/fused-bicyclic（imidazo[ 1,2-b] pyridazine/ imidazo[2,1-b] thiazole） groups were designed and synthesized. A new method for the preparation of the key intermediate compound 11 was proposed. The structures of the target compounds were confirmed by ^1H NMR, IR and MS, and their in vitro antibacterial activities against staphylococcus aureus were evaluated. Among them, compound 16a displays a promising antibacterial activity comparable to that of linezolid.

Design and Synthesis of Lipids Bearing Nucleosides as Gene Vectors

Some novel lipids bearing nucleosides were designed and synthesized as gene vectors, and the structures of these compounds were characterized by UV, IR, 1HNMR, 13CNMR and elemental analysis.

Synthesis of Nucleoside Derivatives Containing Benzophenoxazinone Moiety

Two new nucleoside derivatives containing benzophenoxazinone moiety were synthesized. Their luminescence spectra show that they have strong near infrared fluorescence. Our study provides a new method for direct introduction of near infrared fluorescent probe to bioactive molecules.

Synthesis and Insecticidal Activity of Novel Camptothecin Derivatives Containing Analogs of Chrysanthemic Acid Moieties

Creating high-efifcient and environment-friendly pesticides is very important to produce the pollution free agriculture food and maintain the balance of the survival environmental of the human being. According to reports, camptothecin （CPT） and its derivatives are now being explored as a class of botanical insecticide in agriculture due to its novel mode of action. In order to improve the insecticidal activity of CPT, ten novel camptothecin （1） and 10-hydroxycamptothecin （2） derivatives （1a, 1b, 1c, 1d, 1e;2a, 2b, 2c, 2d, 2e） were designed and synthesized via esteriifcation with analogs of chrysanthemic acid, which have outstanding insecticidal activity. The results showed that compound 2a exhibited potent antifeeding effect and the best contact toxicity among the target compounds against the third-instar larvae of beet armyworm, Spodoptera exigua H＆#252;bner. Compound 2a was also found to be the most effective cytotoxic compound to the tested insect cell lines, IOZCAS-Spex-II, which were established from the fat bodies of S. exigua. It was proposed that the 10-hydroxyl group in the camptothecin derivatives is a key factor for the antifeeding activity of a compound. The nature of the substituents was considered the major factor in determining the insecticidal activity of these compounds.

Synthesis and antiviral activity of 4H-[1,2,5]oxadiazolo-[3,4-d]pyrimidine-5,7-dione 1-oxide nucleosides

A series of 4H-[1,2,5]oxadiazolo[3,4-d]pyrimidine-5,7-dione 1-oxide nucleosides was designed, synthesized and evaluated against vesicular stomatitis virus （VSV） in Wish cell. The antiviral activities of all compounds were stronger than those of acyclovir, while their toxicities were similar to those of acyclovir.

Synthesis and Anti-HIV Activity of Trisubstituted (3′R, 4′R)-3′,4′- Di-O-(S)-camphanoyl-(+)-cis-khellactone (DCK) Analogs

To further explore the potential of DCK analogs as anti-HIV drug candidates, ten new tri-substituted （3＇R,4＇R）-3＇,4＇-di-O-（S）-camphanoyl-（＋）-cis-khellactone （DCK） derivatives （4-13） were designed, synthesized, and evaluated against HIV replication in MT4 cells and H9 lympho- cytes.

Synthesis of Analogs of Phosphoamino Acids and their Biomimic Reactions

In order to further confirm the biomimic properties of N-phosphoamino acids. A series of model compounds, analogue of phosphoryl amino acids, were synthesized and their biomimic mechanism was also investigated by NMR and MS methods. The results indicated that the reactivity of phosphoryl biological small molecules was depended on the configuration, function groups and positions.

Asymmetric Synthesis of Polyhydroxy Pyrrolidinonyl Nucleoside Analogues from Tartaric acid

Asymmetric synthesis of novel optically active nucleoside analogues 7 from natural tartaric acid is described. In the given nucleoside analogues an optically active polyhydroxy pyrrolidinonyl ring is in place of the tetrahydrofuran ring.

MULTIPLE SYNTHESIS OF SMALLPEPTIDE ANALOGS

Two peptide analogs H-Tyr-Thr-Pro-Arg-Lys-OH (1) and H-Tyr-Thr-Pro-Phe-Lys-OH (2) were prepared successfully by the technique of simultaneous multiple peptides synthesis(SMPS) on a single resin support. The profiles of HPLC and amino acid analysis indicated that the purity of 1 and 2 was satisfactory. The average yield(74.9％) of each peptide was reasonable. This new technique of SMPS offered significant savings not only in time but in many expensive reagents as well.

Nucleosides 10: Synthesis of New Derivatives of Pyrimidine and Fused Pyrimidine Nucleosides of Expected Biological Activity

Pyrimidines, such as 6-amino-2-thio and 2-methylthiouracils and fused pyrimidines, such as thienopyrimidines reacted with 1-O-acetyl-2,3,5-tri-O- benzoyl-β-D-ribofuranose to get new derivatives of the corresponding nucleosides. The obtained protected nucleosides were deprotected by methanolic sodium methoxide to get the corresponding free uracil and thienopyrimidine nucleosides. The new nucleosides formed were tested for biological activity against some of microorganism (some fungi and bacteria species). Some of the tested products showed moderate activity and the results were reported.

THE SYNTHESIS OF UNSYMMETRIC ANALOGS OF GOSSYPOL—6-O-METHYLGOSSYPOL

6—O—Mcthylgossypol (3) was obtained with the methods of synthesis for the first time.

Synthesis of F-alkylated MDP Analogs

Four F-alkylated muramyl dipeptides were synthesized by an efficient coupling reagent, Benzotriazol-1-yloxy-bis(pyrrolidino)carbo hexafluoro-phosphate(BBC)([1]).

STEREOSELCETIVE SYNTHESIS OF SOME NUCLEOSIDES

A new method for the synthesis of perbenzylated, peracetylated and perbenzoylated sugar nucleosides has been carefully studied. In this method trichloroacetoxy and trifluoroacetoxy groups were displaced efficiently in the reaction of nucleoside formation as leaving group. And this method was found to be widely applicable in the study of carbohydrate chemistry.

Synthesis of β-L-2',3'-Dideoxy-2'-fluoro-3'-hydroxy-methylarabinofuranosyl Pyrimidine Nucleosides

Dideoxy-2'-fluoro-3'-hydroxymethylarabinofuranosylthymine 10 and cytosine 12 were synthesized from L-xylose and were found to be inactive against HIV-1 in acutely infected lymphocytes.