A convenient synthesis of 5‐alkylthio‐3,4‐diarylisoxazoles by palladium‐catalyzed coupling reactions

Abstract

Palladium‐catalyzed coupling reaction was found effective for rapid access to pharmacologically interesting 3,4‐diarylisoxazoles derivatives as selective COX‐2 inhibitors. Thus, the coupling reaction between 5‐alkylthio‐3‐aryl‐4‐iodoisoxazoles and arylboronic acids afforded the target 5‐alkylthio‐3,4‐diarylisoxazoles in good yields.

Synthetic Approaches towards the Sulfonamide Substituted‐1,5‐Diarylimidazole‐2‐thiones as Selective Cyclooxygense‐2 inhibitors

“…Herein, as part of our ongoing program to design novel selective COX‐2 inhibitors , we describe the synthesis of a novel class of 1,5‐diarylimidazole‐2‐thiones, which for some derivatives need some modifications in standard procedures.…”

Convenient syntheses of 5‐[(2‐methyl‐5‐nitro‐1H‐imidazol‐1‐yl)methyl]‐1,3,4‐oxadiazole‐2(3H)thione and N‐substituted 2‐amino‐5‐[(2‐methyl‐5‐nitro‐1H‐imidazol‐1‐yl)methyl]‐1,3,4‐thiadiazoles

“…Besides, synthesis of 1,3,4-oxadiazole and 1,3,4-thiadiazole derivatives have a great deal of importance because of their broad spectrums of biological characteristics such as anti-inflammatory, anti-fungal and anti-bacterial activities [6][7][8][9][10][11][12][13]. As an extension of our previous work on the synthesis of small bioactive heterocyclic molecules [14][15][16][17], we wish to report the synthesis of 5-[(2-methyl-5-nitro-1H-imidazole-1-yl)methyl]-1,3,4-oxadiazole-2(3H)-thione (10) and its methyl and ethyl thioacetate derivatives 11a-b, and N-substituted 2-amino-5-[(2-methyl-5-nitro-1H-imidazol-1-yl)methyl]-1,3,4-thiadiazoles (13a-f) as possible effective antimicrobial drugs. …”

A New Approach to the Synthesis of 3-Substituted 4-(Diethoxy­phosphoryl)isoxazoles from 3-Azidoalka-1,3-dienylphosphonates

“…4 Isoxazole derivatives form a part of many drugs used for antidepressant therapy and the treatment osteoarthritis or rheumatoid arthritis. 5,6 The introduction of different functional groups in the 3,4-positions of the isoxazole ring, makes it possible to expand the range reactions of 3,4-disubstituted isoxazoles 7,8 and to study their biological properties and, in this context, the synthesis of 3-(3-aryl-4,5-dihydroisoxazol-5-yl)-and 3-alkenyl-4-(diethoxyphosphoryl)isoxazoles is of interest. However, this type of isoxazole has not previously been described in the literature.…”