Synthesis of N-Phosphoryl Branched Peptides

H-phosphonates were conveniently prepared by direct transesterification of diphenyl phosphite (DPP) with the corresponding alcohols, without further purification they were reacted with branched peptide methyl ester (L-Leu2-L-LysOMe) through Atherton-Todd method, a series of different substituted alkyloxy (N-phosphoryl-L-Leu)2-L-LysOMe were synthesized, and their stmctures were confirmed by ^31P NMR, ESI-MS, ^1H NMR, ^13C NMR, IR and elemental analysis. The approach possesses the advantages of easy operation, high yield and inexpensive phosphorylating reagent.     

Synthesis and Biological Activities of N-Phosphoryl Branched Peptides

Much research has shown that some N-phosphoryl peptides are endowed with important biological activities. For instance, Na-(diaryloxyphosphoryl)-L-alanyl-L-prolines are moderate inhibitors of angiotensin converting enzyme and yield highly potent inhibitors when they hydrolyze under physiological condition lossing 1 mol phenol1; Phosphoramido (N-[(a-rhamnopyranosyloxy)hydroxyphosphinyl]-L-Leu-L-Trp) and its analogues have been shown to be inhibitors of endothelin converting enzyme, therefor…     

Synthesis of Novel Dendrimers Containing Amino Acids and Peptides

Dendrimers are known for their well-defined, regular, highly branched architectures with a large number of functional groups1. Recently, dendrimers have been widely researched in different fields, such as molecular light havesting, catalysts, liquid cryst…     

Synthesis and Biological Activities of Substituted Triazolethione Schiff Base

Six novel Schiff bases have been synthesized by the condensation reaction of 4-amino-5-（4-pyridyl）-2,4-dihydro-1,2,4-triazole-3-thione with various benzaldehydes. The sfructures of the compounds have been confirmed by ^1H NMR, IR and elemental analysis. The preliminary bioassay indicated that the title compounds possessed good fungicidal activities to several vegetable pathogens.     

N—（4,6—二甲氧基嘧啶—2—基）—N‘—磷酰基脲类衍生物的及生？…

利用二氯磷酰基异氰酸酯与４，６－二甲氧基－２－氨基嘧啶的加成反应合成了中间体Ｎ－（４，６－二甲基嘧啶－２－基）－Ｎ’－二氯代磷酰基脲，Ⅰ与２倍的醇或胺反应得到对称双取代磷酸基脲类化合物Ⅱａ－Ⅱｉ，Ⅰ与１倍的受反应得到氯代磷酰基脲类化合物Ⅲａ－Ⅲｅ，再与Ⅰ１倍的醇反应则得到不对称双取代磷酰基脲类化合物Ⅳａ－Ⅳｇ。     

Synthesis and Biological Activity of Tonghaosu Analogs Containing Phenoxy-phenyl Moiety

A new series of phenoxy-phenyl moieties containing tonghaosu analogs with varied B-ring 9 were synthesized and characterized by spectral studies. Their insect antifeedant activity against Pieris brassicae and insecticidal activity against Culex quinquefasciatus were investigated. Compound 9e exhibited excellent antifeeding activity.     

Synthesis, Structure and Biological Activities of Novel Triazole Compounds Containing N,N-Dialkyldithiocarbamate Moiety

Introduction As an important type of fungicides, triazole compounds are highly efficient, low poisonous and inward absorbent.1-3 At present, the studies on triazole derivatives are mainly concentrated on compounds with triazole as the only active group. The report of triazole compounds that contain both triazole group and other active group in a single molecule has rarely been found. Dialkyl-substituted dithiocarbamate salts have also shown interesting biological effects.4 N,N-Dialkyldithio-…     

Short Synthesis of C-terminal Modified Peptides by a Series-connection Procedure

Three peptide alcohols and four peptidyl N-akyl-amides were prepared by a series-connection procedure consisting of n-1 sequencial assembly on solid support followed by ammonolysis with glycinol, benzylamine or n-butylamine, and successive extractionelution through C-18 layer. All products were obtained from this procedure without further purification,in an overall yield of 75-86%.     

Synthesis and Biological Activity of Philanthotoxin Analogs

Sodium ion channels, acetylcholine esterase and neurotransmitter receptors in insect neurons and skeletal muscles are often made as target by practical neurotoxic pesticides. But insects can create resistance after using a pesticide for a long time. So th…     

Design and Synthesis of Muramyl Dipeptide Cyclic Analogue

A new conformationalloy restricted cyclic analogue of muramyl dipeptide was designed and manually synthesized by our “Meshed-Bag Gathered-Bunch” method with a combination of Fmoc,ally and N-1-(4,4-dimethyl-2,6-dioxocyclo-hexylidene) ethyl chemical protection strategy.     

Synthesis of Fragment Derivatives of Delta Sleep-inducing Peptide （1-4） Catalyzed by Enzymes in Organic Solvents

Synthesis of two fragment derivatives of delta sleep-inducing peptide (DSIP) (1-4), Boc-Trp-Ala-Gly-GlyNHNHPh (1) and Boc-Trp-Ala-Gly-GlyOEt (2), catalyzed by proteases via 2 2 or 1 3 synthetic routes with different protecting groups at C-terminal in organic solvents was reported. The yield of N-Boc tetrapeptide with phenylhydrazinyl protecting carboxyl group at C-terminal (1) was higher than that of N-Boc tetrapeptide ethyl ester (2) by 2 2 route. The factors influencing the synthetic yield of the fragments of DSIP (1-4) were discussed.     

Simple, Mild and Convenient Synthesis of Two Novel N-Dichloro-acetyl Oxazolidines and their Biological Activities

Two N-dichloroacetyl oxazolidines were synthesized with a simple, mild and convenient method. All the compounds were characterized by IR, ^1HNMR and elemental analysis. The preliminary biological test showed that the compounds protected maize against injury by some herbicides to some extent.     

Studies on Synthesis and Biological Activities of Novel Triazole Compounds Containing Pyrimidine or N, N－Dialkyldithiocarbamate Ring

Twelve of the title compounds were synthesized. Their structures were identified by means of IR, EA, IH NMR and MS. The IR spectra clearly show that the absorptions in the regions of 1716—1666 cm^-1 and 1505—1499 cm^-1 are the characteristic absorption bands for vc=O and vc=N. In the IH NMR spectra of target compounds(10a—10g), three protons of a = CH—CH2— group present three sets of quartet peaks of the protons. The preliminary bioassays showed that the synthesized compounds exhibited some activities of fungicides and plant growth regulators.     

Syntheses and Biological Activities of Ethyl N-Hydroxy-N-（substituted） phenyloxamates as KARI Inhibitors

Nine ethyl N-hydroxy-N-(substituted)phenyloxamates(2a—2i), based on the structure of the KARI inhibitor IpOHA, were synthesized. Their structures were established on the bases of 1H NMR, IR, ESI-MS and elemental analyses. Among the nine compounds, four show in vitro inhibitory activity on rice KARI, with 2c and 2g[Ki values of (35.2±4.9) and (49.4±6.3) μmol/L] having similar activity to the precursor of IpOHA(A, Ki=34.1±6.7 μmol/L). The results will be helpful to further molecular design of more potent KARI inhibitors.     

Convenient Synthesis of Two Novel Oxazolidines and Primary Research on their Biological Activities

Herbicide safeners selectively protect crop plants from herbicide damage without reducing activity in target weed species. These compounds have generated consider- able commercial interest and research activity since the phenomenon of herbicide safening w…     

Synthesis and Biological Activities of 3—（2—Furyl）—4—aryl—1,2,4—triazole—5—thiones

A series of novel compounds 3-(2-furyl)-4-aryl-1,2,4-triazole-5-thiones have been synthesized.All the compounds were characterized by spectral data and elemental analysis. The preliminary biological test showed that some of them exhibited excellent plant-growth regulative activities.     

Construction and Analysis of N-phosphoryl Peptide Libraries

N-Phosphoryl peptide libraries were constructed by transformation from homo-oligopeptide libraries, which was synthesized by self-assembly of amino acids with the assistance of phosphorus oxychloride. Electrospray ionization mass spectrometry (ESI-MS) was used to monitor the reaction.     

Synthesis of Boswellic Acid Derivatives and Primary Research on their Activities

In order to search for new potent anti-cancer agents, a series of boswellic acid derivatives were designed and synthesized. Six of them were identified by IR, NMR and MS as new compounds and biologic assay of anti-cancer is underway.     

Two Series of Synthetic Territrem B Analogues and their Biological Activities

Two series of territrem B analogues (6, 11) were designed and synthesized from jujubogenin 2. Compound llc inhibited AChE with the ratio of 70% at 10^-4 mol/L. Compounds5a, 5b, 6a and lib showed moderate cytotoxicity on cultured KB cells at 10^-6 mol]L.Compounds 5c and 6b alleviated injury arising from oxygen-glucose deprivation (OGD).     

A Study on bioactivity of Corn Peptides with Low Molecular Weight（Ⅰ）——Effect of an Intake of them on Alcohol Metabolism in Rats

IntroductionIn the past few years,some researchers foundthat small peptides derived from the hydrolysate offood protein play an important role in regulatingautonomic nervous system,activating the cellularimmunity function,ameliorating the cardiovascularfunction,antioxidizng and antaging,etc.[1— 8] .Par-tial proteolysis is effective for improving the func-tional properties of protein.Small peptides havesome advantages compared to protein,such as lowosmotic pressure,fast absorption,good taste a…