Synthesis of Novel Ligustrazine Derivatives as Potential Platelet Aggregation Inhibitors

Ligustrazine (lig; tetramethylpyrazine, TMP; Figure 1) is one of major efficient components from Chinese traditional medicine herb Ligusticum Chuanxiong Hort, which is currently widely used in China for the treatment of coronary atherosclerotic cardiovasc…     

The Synthesis of Diphenyl Phosphonate Analogues of α-Amino Acids as Enzyme Inhibitors

Abstract

α-Aminoalkylphosphonic acids are analogues of natural aminoacids and as such have been the subject of much research effort over past years¹. The diphenyl esters of α- aminoalkylphosphonic acids are particularly potent and show high selectivity as irreversible inhibitors of serine proteinases. Thus far, α-aminoalkylphosphonic acid ester analogues of a number of aliphatic- and aromatic aminoacids have been prepared including valine, phenylalanine, tryptophan, and tyrosine², and the basic aminoacids ornithine, lysine. etc.³. We have now also prepared the a-diphenyl phosphonate analogues of the acidic aminoacids, aspartic and glutamic⁴. These have been examined as potential inactivators of serine proteinases exhibiting a P₁ specificity for aspartate and glutamate, e.g. S. aureus V8 protease and granzyme B.     

Graphene Oxide as Recyclable Catalyst for One-Pot Synthesis of α-Aminophosphonates

We report the synthesis of α-aminophosphonates from aromatic aldehydes, aromatic and aliphatic amines, and trimethylphosphite (Kabachnik–Fields reaction) using a “carbocatalyst,” graphene oxide, at room temperature with excellent yield and recyclability. Enhanced catalytic activity of graphene oxide as compared to other catalysts studied is possibly due to the presence of carboxylic acid and hydroxyl groups.     

New One-Pot Synthesis of ò-Iodoalkyne

A high yielding, one-pot general procedure for the synthesis of ò-iodoalkyne is described.     

Synthesis of a Novel Series of S-Alkyl Thiobenzoate Compounds as Farnesyltransferase Inhibitors

S-akyl thiobenzoate compounds were designed as farnesyltransferase (FTase) inhibitors. An effective synthetic method was explored. The structures of the target compounds were elucidated by NMR spectral and elemental analysis.     

One-Pot Synthesis of Pyrazolyl-Containing α-Aminophosphonates

Abstract

A series of novel pyrazolyl-containing α-aminophosphonates were synthesized by one-pot reaction from 4-formylpyrazole, substituted aromatic amines, and dialkylphosphites. The synthesized compounds were characterized by elemental analysis, ¹H NMR, and IR spectroscopy. Single-crystal X-ray diffraction data of compounds 4a and 5b were obtained, and some of these compounds showed inhibitory effect on eggplant-infecting Botrytis cinerea.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Tables S1-S4. Figures S1 and S2 .cif files.     

One-Pot,Three-Component Coupling Reaction: Catalyst-Free Green Synthesis of Novel N-Heteroaryl α-Naphthylglycines

A series of novel N-heteroaryl α-arylglycines containing naphthol rings has been prepared by one-pot, three-component condensation reaction of glyoxalic acid, heteroaryl amines and naphthols in water at ambient temperature and under reflux conditions in moderate to high yields. The promising advantages such as removal of organic solvent, no need to catalyst, simplicity of the reaction procedure and easy product separation will be discussed in this article.     

Syntheses of Some Sulfur‐Containing Polyunsaturated Fatty Acids as Potential Lipoxygenase Inhibitors

Starting from (all‐Z)‐eicosa‐5,8,11,14,17‐pentaenoic acid (EPA) and (all‐Z)‐4,7,10,13,16,19‐docosahexaenoic acid (DHA), several polyunsaturated fatty acids, containing a sulfur atom either in the chain or in a thiophene ring, have been synthesized as potential inhibitors of lipoxygenases.     

Convenient One-Pot Synthesis of dℓ-Pyrocin

Abstract

Treatment of readily available monomethyl maleic acid (1) with three equivalents of methyl magnesium iodide followed by an excess of 2-methyl-1-propenyl magnesium bromide and a catalytic amount of CuBr produces d?-pyrocin (3) in a high yield.     

Synthesis of 4-(4-Methylsulfonylphenyl)-3-phenyl-2(3H)-thiazole Thione Derivatives as New Potential COX-2 Inhibitors

Synthesis of novel 4-（4-methylsulfonylphenyl）-3-phenyl-2（3H）-thiazole thione derivatives with functionalized diarylheterocycle pharmacophore as potential COX-2 inhibitors was described. The title compounds were synthesized by cyclocondensation of corresponding dithiocarbamate and 2-bromo-1-（4-methylsulfonylphenyl）ethanone, followed by dehydration with H2SO4. All of the target compounds were characterized by ^1H NMR, IR and mass spectral data.     

Synthesis and Evaluation of Coumarin–Resveratrol Hybrids as 15-Lipoxygenaze Inhibitors

A series of coumarin–resveratrol hybrids, 3-arylcoumarin derivatives 3a–u, were synthesized through the intermolecular condensation reaction of various salicylaldehydes and phenylacetic acids in the presence of 1,4-diazabicyclo[2.2.2]octane under solvent-free conditions. All the synthesized compounds were screened for their inhibitory potency against soybean 15-lipoxygenase. Among them, three compounds (3c, 3j, and 3q) showed good enzyme-inhibitory activities.     

Synthesis of Novel Spin‐Labeled Derivatives of Podophyllotoxin as Potential Antineoplastic Agents

Five novel nitroxyl spin‐labeled ester derivatives of podophyllotoxin have been prepared by reacting the corresponding N‐(1‐oxyl‐2,2,6,6‐tetramethyl‐4‐piperidinyloxycarbonyl) amino acids with the hydroxy group of podophyllotoxin in the presence of dimethylaminopyridine and N,N‐dicyclohexylcarbodiimide and evaluated as potential antitumor agents. All of the target compounds showed more significant cytotoxicity against P‐388 murine leukemia and A‐549 human lung carcinoma in vitro than etoposide.     

Design, Synthesis and Biological Activity of Substituted-N-[4-（substituted-phenylsulfamoyl）phenyl]benzamide as Potential AHAS Inhibitors

Acetohydroxyacid synthase (AHAS) is an ideal target for the design of environmental benign herbicides, because it catalyzes the first step in the biosynthesis of branched chain amino acids, which does not exist in mammal bodies1-4. Typical AHAS inhibitors…     

Synthesis of β-Amino Phosphonates in One-Pot Procedure

Abstract: β-amino phosphonate derivatives are synthesized in one-pot procedure via reduction of β-enamino phosphonate intermediates with NaBH₄/acetic acid or trifluoroacetic acid.     

Facile and Efficient One-Pot Synthesis of β-Carbolines

Initial formation of tetrahydrocarboline 3 from tryptophan methyl ester 1 and aldehyde 2 by Pictet–Spengler reaction, followed by treatment with trichlorocyanuric acid, provides a facile and efficient route for a one-pot synthesis of β-carbolines with excellent yields.     

Synthesis and Biological Evaluation of Analogs of Methyl Ursolate 3-O-β-Chacotrioside as H5N1 Viral Entry Inhibitors

The earliest stage of influenza virus infection is the viral entry to the host cell. In our previous work, we discovered the first three small molecule H5N1 viral entry inhibitors 1–3. Here, based on saponin 3, methyl ursolate 3-O-β-chacotrioside, several analogs were synthesized and evaluated to understand the structure-activity relationships of this type of compound on the H5N1 viral entry inhibitory activity. The preliminary studies demonstrated that unlike saponins 1 and 2, it is possible to reduce the 3-O-chacotriosyl residue of compound 3 to a disaccharide without affecting the viral entry activities significantly. The results obtained will render new clues to the understanding of the antiviral profile for these types of compounds.     

Nano-ZnO Impregnated on Starch—A Highly Efficient Heterogeneous Bio-Based Catalyst for One-Pot Synthesis of Pyranopyrimidinone and Xanthene Derivatives as Potential Antibacterial Agents

Russian Journal of Organic Chemistry - A new method has been proposed for the synthesis of pyranopyrimidinone and xanthene derivatives using zinc oxide–starch nanocomposite as catalyst under...