Synthesis and antioxidant activity of some thiazolidin-4-one derivatives

Abstract  4-Fluorobenzaldehyde was used for the preparation of 2-(4-fluorophenyl)thiazolidin-4-one derivatives which were allowed to react with chloroacetonitrile and acrylonitrile to produce 3-(2-(4-fluorophenyl)-4-oxothiazolidine3-yl)acetonitrile and 3-(2-(4-fluorophenyl)-4-oxothiazoledine-3-yl)propanenitrile. Biological evaluation of some of the compounds showed that many had promising antioxidant activity. Graphical Abstract        

Synthesis and spectroscopic investigation of some arylazo derivatives of thiazolidin-4-one

The reaction of 2-phenylimino- and 2-(p-tolylimino)thiazolidin-4-ones with benzene-, p-nitrobenzene, p-sulfamoylbenzene-, and p-toluenediazonium chlorides in glacial acetic acid in the presence of anhydrous sodium acetate (pH of the medium 4.5–5.0) has been studied. A spectroscopic investigation in the IR and UV regions has shown that the 5-(p-nitrophenylazo) derivatives of thiazolidin-4-one exist in the azo tautomeric form; the 5-phenylazo and p-tolylazo derivatives of thiazolidin-4-one are mixtures of the azo and hydrazone tautomers.     

Stereoselective synthesis of partially protected azasugar derivatives

Five-membered azasugar derivatives with partially protected hydroxyl groups, and their fluorinated derivatives were synthesized via the key intermediates of norbornyl-like bicyclic acetals using d-xylose and d-glucose as starting materials. The glycosylation of the azasugar intermediate and 1-methylenesugar was also explored. Translated from Chemical Journal of Chinese Universities, 2006, 27 (4) (in Chinese)     

Design,synthesis and antifungal activity of novel selenochroman-4-one derivatives

A series of novel selenochroman-4-one derivatives bearing semicarbazone or nitrogen heterocycle was designed, synthesized, tested antifungal activity and characterized via ¹H-NMR, ¹³C-NMR, and HRMS. The design of the compounds is based on the principle of molecule hybrid and bioisosterism. We aimed at attaching semicarbazones or nitrogen heterocycle to the selenochroman-4-one for enhancing antifungal activity. The antifungal activity of target compounds was evaluated using the microdilution broth method in vitro test. Bioassay results indicated that some of the derivatives displayed good fungistatic activity on Candida zeylanoides, Candida albicans, Cryptococcus neoformans, resistant to fluconazole strain 103 (Candida albicans), resistant to fluconazole strain 100 (Candida albicans) and strain SC5314 (Candida albicans). All the compounds exhibit antifungal activities against the tested funguses in different levels, among them, 7 compounds of antifungal activity against several funguses is better than that of the control drug fluconazole. Based on the results, preliminary structure activity relationships (SARs) were summarized to serve as a foundation for further investigation.     

A practical and efficient synthesis of five-membered azasugar derivatives

A practical and efficient synthesis of 1,4-dideoxy-1,4-imino-D-arabinol and its partially protected derivatives has been described via the key intermediate with a norbornane-like structure using D-glucose as a starting material. __________ Translated from Chinese Journal of Organic Chemistry, 2007, 27(8): 1013–1017 [译自: 有机化学]     

Synthesis and antiviral activities of novel 1,4-pentadien-3-one derivatives bearing an emodin moiety

A series of 1,5-diaryl-1,4-pentadien-3-one derivatives bearing an emodin group were designed and synthesized by the combination of natural products. The antiviral activities against tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV) in vivo were evaluated. Some of the derivatives displayed promising curative effect and protective activity against TMV. Compound D5 showed appreciable curative bioactivity on TMV approximately of 50% at 306.2 mg/mL, which was superior to ningnanmycin (409.3 mg/mL).     

A novel highly stereoselective synthesis of 2,3-disubstituted 3H-quinazoline-4-one derivatives

[structure: see text]. An efficient three-step synthesis of chiral 3H-quinazoline-4-one derivatives from commercial materials is disclosed. The Mumm reaction of imidoyl chloride with alpha-amino acids followed by reductive cyclization affords enantiomerically pure (ee >93%) quinazoline-4-ones in good overall yield. A comparison with existing approaches indicates that this method is superior for hindered substrates.     

An efficient synthesis of new thiazolidin-4-one fused s-triazines as potential antimicrobial and anticancer agents

As a part of our endeavor toward the synthesis of new heterocyclic bioactive agents, two series of thiazolidin-4-one fused s-triazines were synthesized by applying an efficient palladium catalyzed C–C Suzuki coupling using catalyst system Pd(OAC)₂, Xphos and K₃PO₄ as a base in toluene solvent. Moreover, the synthesized analogs were further screened for their in vitro antimicrobial as well as anticancer efficacy against prostate cancer PC3 cells. Some compounds displayed remarkable antimicrobial activity and noticeable anticancer activity. It was observed that, both benzonitrile and nicotinonitrile are essential to increase the different pharmacological activities. The newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR and MS analysis.     

Stereoselective synthesis of 4-hydroxymethyl-1,3-oxazolidin-2-one derivatives from novel 2-hydroxymethylaziridines

A stereoselective and simple method for the synthesis of trans-2-hydroxymethyl-N-alkyl-1,3-oxazolidin-2-ones is described. The synthesis involved the reduction of trans-aziridine-2-carboxylates with LiAlH₄, followed by a ring opening and a cyclization reaction in the presence of methyl chloroformate to afford the target trans-oxazolidinones in completely regio- and stereoselective process. A plausible reaction mechanism has been proposed involving an S_N1 pathway and a detailed computational study of this mechanistic process has been carried out using theoretical calculations.     

Efficient synthesis of novel quinazoline-4(1H)-one derivatives by N-halosulfonamides

Research on Chemical Intermediates - In this research, a facile, effective and one-pot synthesis of new quinazoline-4(1H)-one derivatives is reported. Isatoic anhydride, acid hydrazides or ammonium...     

Efficient asymmetric synthesis of an azasugar in water

An extremely efficient asymmetric synthesis of a pyrrolidine azasugar was completed in only four steps in water, without the use of protecting groups and in 60% overall yield from a simple, achiral bis-electrophile.     

A facile synthesis of novel 1,4-benzoxazepin-2-one derivatives

An efficient and simple synthesis of 1,4-benzoxazepin-2-one derivatives has been achieved via the reaction of isoquinoline, activated acetylenes, and 1-(6-hydroxy-2-isopropenyl-1-benzofuran-yl)-1-ethanone in water without using any catalyst. This one-pot reaction occurs in high yields under mild conditions.     

Domino synthesis of novel series of 4-substituted 5-thioxo-1,2,4-triazolidin-3-one derivatives

The efficient synthesis of 4-substituted 5-thioxo-1,2,4-triazolidin-3-one derivatives (4-substituted thiourazoles) via domino combination of thiophosgene, aliphatic or aromatic amines, and ethyl carbazate is presented.     

Design,synthesis and immunomodulating activity of C-pseudonucleosides containing thiazolidin-4-one and phenyl connected by acetamide bond

Several novel C-pseudonucleosides containing thiazolidin-4-one and phenyl connected by acetamide bond were rationally designed and easily synthesized at room temperature by using the unprotected sugar aldehyde as the starting material. The effects of the compounds on Con A-induced T cell proliferation were evaluated at five concentrations of 5, 10, 25, 50, and 100 mmol/L Interestingly, compounds 7a and 8a (n = 2, R = H) exhibited immunostimulating activities, while compounds 5a, 6a (n = 1, R = H) and 7b, 8b (n = 2,R = CH₃) showed immunosuppressive activities. Another two compounds 5b and 6b (n = 1,R = CH3) had no immunomodulating activities. These initial biological results suggested that subtle structural changes to the phenyl and acetamide bond of C-pseudonucleosides could have a significant effect on T cell proliferation bias, although it was difficult to formulate a rigorous structureactivity relationship based on the observed activities.     

Design,synthesis and antibacterial activity of novel pleuromutilin derivatives with 4H-pyran-4-one and pyridin-4-one substitution in the C-14 side chain

A series of novel pleuromutilin derivatives with 4H-pyran-4-one and pyridin-4-one substitution in the C-14 side chain have been designed and synthesized. In vitro antibacterial activity evaluation showed that most of the derivatives exhibited potent antibacterial activity against drug resistant Gram-positive strains. Compounds 12a, 12d, and 28 are the most active derivatives in this series, displaying activity comparable to that of retapamulin and BC-3781. As the metabolic stability of this series is not satisfactory, further modifications are going on to improve their pharmacokinetic profile.     

Preparation of novel pyrrol-2-one derivatives via an effective synthesis of new oxazole scaffold

A convenient procedure for the preparation of oxazole and pyrrole derivatives is described. 2-Amino-1,3-oxazol-2-ones 3a,b were first synthesized from the cyclocondensation reactions of cyanamide (2) with 4-ethoxycarbonyl-5-aryl-2,3-furandione 1a,b, and then new pyrrol-2-ones 5 were synthesized from the reaction of the compounds 3 with various aromatic amines 4.     

Efficient and structurally controlled synthesis of novel polyhydroxylated indolizidine derivatives with an amino group

Novel polyhydroxylated indolizidine derivatives containing an amino group have been efficiently and divergently synthesized from azasugar aldehyde. The key steps of the strategy involved an effectively microwave assisted 1,3-dipolar cycloaddition of azasugar nitrone and methacrylate for installing a potential amino group and an ester group with a extended chain, and a structurally controlled intramolecular cyclo-amidation for constructing the indolizidine ring system via a key tricyclic indolizinone-containing intermediate.     

Regioselective Friedel-Crafts acetylation of 5-hydroxyindole derivatives: synthesis of 4H-pyranoindol-4-one derivatives

The Friedel-Crafts acetylation of 5-hydroxyindole derivativesla-c regioselectively produced 6-acetyl-5-hydroxy-indole derivatives2a-c which were condensed with cinnamic acid using POC1₃ and dry pyridine to afford 5-cinnamoyloxy-6-acetyl-indoles3a-c. These upon Baker-Venkataraman transformation furnished 6-cinnamoylacetyl-5-hydroxyindoles4a-c which were cyclised separately with AcOH/HCl and Ac₂O/AcONa to 4H-pyrano-(2,3-f)indol-4-one derivatives5a-c and6a-c respectively.