Aim:
The reactions were carried out by one pot three-component synthesis, 3-cyanoacetylindole (1) on reaction with aromatic aldehydes (2) and β-naphthol (3) in an aqueous medium in presence of L-proline as a catalyst under reflux for 30 min, resulted (3-amino-1-phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3-yl)methanone (4). The method has many advantages like short reaction times, good yields and simple workup procedure besides being green in nature. Pharmacological evaluation of title compounds was done for anti-inflammatory and analgesic activities. Anti-inflammatory activity was carried carrageenan-induced paw edema model in which indomethacin was used as standard and analgesic activity was evaluated by eddy's hot plate method using diclofenac as standard drug.
Background:
Benzopyrans or chromenes are an important class of heterocyclic compounds due to their broad spectrum of biological activity and a wide range of applications in medicinal chemistry. The chromene moiety is found in various natural products with interesting biological properties. Chromenes constitute the basic backbone of various types of polyphenols and are widely found in alkaloids, tocopherols, flavonoids and anthocyanins. Indoles are omnipresent in various bioactive compounds like alkaloids, agrochemicals and pharmaceuticals.
Objective:
To synthesize one-pot stepwise Green synthesis, anti-inflammatory and analgesic activities of 3-amino-1-phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3-yl)methanones
Methods:
The acute anti-inflammatory effect was evaluated by carrageenan-induced mice paw edema (Ma Rachchh et al., 2011). Edema was induced by injecting carrageenan (1% w/v, 0.1 ml) in the right hind paw of mice. The test compounds 1-12, indomethacin (10 mg/kg) and the vehicle were administered orally one hour before injection of carrageenan. Paw volume was measured with digital plethysmometer at 0, 30, 60, 90, 120 min after injection.
Percentage increase =A-B/ A *100
Results:
Carrageenan Induced paw edema model was used for Anti-inflammatory activity in which animals treated with standard (indomethacin) and test compounds showed a significant decrease in the paw edema. Analgesic activity was estimated by using Eddy’s hot plate method; animals were treated with standard (diclofenac) and test compounds showed a significant increase in the reaction time.
Conclusion:
A green, One-pot, step-wise and three-component synthesis of 3-amino-1-phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3-yl) methanone was achieved by using water as a solvent, L-proline as catalyst under reflux conditions. The reactions were carried out in eco-friendly conditions with shorter reaction times, easier workup and high yields. Anti-inflammatory activity was evaluated by carrageenan-induced paw edema model where significant anti-inflammatory activity is shown by all the test compounds (4a-l) when compared to standard drug. Analgesic activity was studied by Eddy’s Hot plate method and Test compounds 4e, 4f, 4h, 4i, 4j, 4k, 4l showed significant activities when compared to the reference drug.
Evaluation of analgesic and anti-inflammatory activity of ethanolic extract of Enhydra fluctuans on male wistar rats