ABSTRACT
Chromone-2-carboxylate scaffold is growing as an important pharmacophore in medicinal chemistry with diverse biological properties. We have developed a facile one-pot transformation of 2-fluoroacetophenone directly to chromone-2-carboxylate scaffold in a single step via a tandem C-C and C-O bond formation. The majority of the previously reported medicinal chemistry synthetic protocols primarily used only one procedure which follows a two-step strategy that needs to start with "2-hydroxyacetophenone". Our methodology not only serves as an alternative one-pot methodology but also allows chemists to start from different raw materials (2-fluoroacetophenone) other than the traditional ortho-hydroxyacetophenone for maintaining the regioselectivity in the cyclization step. We further demonstrated the utility of our protocol by successfully extending the application to the synthesis of two natural products (Halenic acids A and B), various bis-chromones including drug molecules (DSCG, cromoglicic acid), and potent anti-Alzheimer compound (F-cromolyn). This methodology can serve as a promising alternative tool for finding new bioactive chromones with diverse modifications due to the opportunity to use new raw materials in the synthesis of chromones.
Subject(s)
Chromones , Pharmacophore , Chromones/chemistry , Molecular Structure , Acids , Cyclization , Carboxylic AcidsABSTRACT
An efficient method for the synthesis of 2,5-dihydroisoxazoles and isoxazoles using iodocyclization of N-alkoxycarbonyl O-propargylic hydroxylamines has been developed. 2,5-Dihydro-4-iodoisoxazole underwent the cross-coupling reactions without aromatization to afford polyfunctionalized 2,5-dihydroisoxazoles. This process was applied to the preparation of valdecoxib and its 2,5-dihydro-derivative.
Subject(s)
Hydroxylamines/chemistry , Iodine/chemistry , Isoxazoles/chemistry , Cyclization , Oxidation-ReductionABSTRACT
A library of 1-(1',2,3,3',4,4',6-hepta-O-acetyl-6'-deoxy-sucros-6'-yl)-1,2,3-triazoles have been investigated for their antibacterial, antifungal and cytotoxic activities. Most of the target compounds showed good inhibitory activity against a variety of clinically and food contaminant important microbial pathogens. In particular, 1-(1',2,3,3',4,4',6-hepta-O-acetyl-6'-deoxy-sucros-6'-yl)-4-(4-pentylphenyl)-1,2,3-triazole (5) was highly active against all the tested bacteria with minimal inhibitory concentrations (MICs) ranging between 1.1 and 4.4 µM and bactericidal concentrations (MBCs) from 2.2 and 8.4 µM. The compound 1-(1',2,3,3',4,4',6-hepta-O-acetyl-6'-deoxy-sucros-6'-yl)-4-(4-bromophenyl)-1,2,3-triazole (3) showed antifungal activity with MICs from 0.6 to 4.8 µM and minimal fungicidal concentrations (MFCs) ranging between 1.2 and 8.9 µM. Furthermore, some of the compounds possessed moderate cytotoxicity against human breast, lung, cervical and hepatocellular carcinoma cell lines, without showing toxicity for non-tumor liver cells. The above mentioned derivatives represent promising leads for the development of new generation of sugar-triazole antifungal agents.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antifungal Agents/pharmacology , Antineoplastic Agents/pharmacology , Sucrose/pharmacology , Triazoles/pharmacology , Anti-Bacterial Agents/chemical synthesis , Antifungal Agents/chemical synthesis , Antineoplastic Agents/chemical synthesis , Cell Line, Tumor , Cell Survival/drug effects , Dose-Response Relationship, Drug , Female , Gram-Negative Bacteria/drug effects , Gram-Negative Bacteria/growth & development , Gram-Positive Bacteria/drug effects , Gram-Positive Bacteria/growth & development , Hepatocytes/cytology , Hepatocytes/drug effects , Humans , Microbial Sensitivity Tests , Mitosporic Fungi/drug effects , Mitosporic Fungi/growth & development , Organ Specificity , Primary Cell Culture , Species Specificity , Structure-Activity Relationship , Sucrose/analogs & derivatives , Sucrose/chemical synthesis , Triazoles/chemical synthesisABSTRACT
1',2,3,3',4,4',6-Hepta-O-benzyl-6'-N-methacryloyl-6'-deoxysucrose 1, 6'-deoxy-6'-N-methacryloyloxyethylureido sucrose 2 and 6,6'-dideoxy-6,6'-N-dimethacryloyloxyethylureido sucrose 3 have been homo-polymerized and copolymerized with styrene by a free radical process, yielding polymer materials with pendant sucrose moieties, attached to the polymer backbone via amide linkages. The results demonstrated that varying the structural features of the monomers, greatly affected the thermal and rheological properties of the polymers. The polymer materials obtained have been characterized by NMR, MALDI-TOF, DSC, AFM and EWC (equilibrium water content). The efficient synthesis of the three novel, regioisomerically pure, N-methacryloylamide sucrose-containing monomers (1, 2 and 3) have been described.
Subject(s)
Amides/chemical synthesis , Methacrylates/chemical synthesis , Polymers/chemical synthesis , Sucrose/chemical synthesisABSTRACT
Novel 1-(1',2,3,3',4,4',6-hepta-O-acetyl-6'-deoxy-sucros-6'-yl)-4-substituted-1,2,3-triazoles were synthesized by microwave assisted copper catalyzed 1,3-dipolar cycloaddition of sucrose derived azides with terminal alkynes in excellent yields and in short reaction times. The compound 1',2,3,3',4,4',6-hepta-O-acetyl-6'-azido-6'-deoxy-sucrose was regioselectively synthesized from sucrose by improved procedure and used for the cycloadditions. By combining carbohydrate and 1,2,3-triazole structural motifs, a library of 1,2,3-triazole-sucrose conjugates have been obtained.