Shagufta Khatoon’s research while affiliated with University of Karachi and other places

To evaluate the effect of substituents on biological activities of electron-rich N-containing heterocycles, the variably 2-substituted 5,6-dihydro-5-oxo-4H-1,3,4-oxadiazine-4-propanenitriles 26–33 were synthesized and evaluated for antibacterial, antifungal, and enzyme-inhibition activities. The target compounds were obtained from alkyl 4- or 3-hydroxy benzoates 1 and 2, respectively, and from methyl indoleacetate 3. The phenolic OH group of benzoates 1 and 2 were substituted with p-toluenesulfonyl (→4 and 5), benzoyl (→6 and 7), and benzyl groups (→8 and 9) and then converted to 5,6-dihydro-5-oxo-4H-1,3,4-oxadiazine-4-propanenitriles. To establish structure-activity relationships (SAR), a pharmacological screening of the intervening intermediates was also conducted, which revealed that the intermediate hydrazide 11 possesses significant antimicrobial and MAO-A inhibiting properties and intermediates 12, 24, 28, and 29 appreciable antifungal activities. Compound 7 inhibits α-chymotrypsin.

To evaluate the effect of substituents on biological activities of electron-rich N-containing heterocycles, the variably 2-substituted 5,6-dihydro-5-oxo-4H-1,3,4-oxadiazine-4-propanenitriles 26-33 were synthesized and evaluated for antibacterial, antifungal, and enzyme-inhibition activities. The target compounds were obtained from alkyl 4- or 3-hydroxy benzoates 1 and 2, respectively, and from methyl indoleacetate 3. The phenolic OH group of benzoates 1 and 2 were substituted with p-toluenesulfonyl (→ 4 and 5), benzoyl (→ 6 and 7), and benzyl groups (→ 8 and 9) and then converted to 5,6-dihydro-5-oxo-4H-1,3,4-oxadiazine-4-propanenitriles. To establish structure-activity relationships (SAR), a pharmacological screening of the intervening intermediates was also conducted, which revealed that the intermediate hydrazide 11 possesses significant antimicrobial and MAO-A inhibiting properties and intermediates 12, 24, 28, and 29 appreciable antifungal activities. Compound 7 inhibits α-chymotrypsin.

The dichloromethane fraction from Areca catechu was found to inhibit monoamine oxidase type A isolated from the rat brain with an IC50 of 665 +/- 65.1 microg/ml. Studies with pharmacological models of depression, i.e., forced swim and tail-suspension tests, indicated that it caused significant reduction in the immobility time similar to that of moclobemide (a selective inhibitor of MAO-A) without causing a significant change in motor performance. Alkaloids such as arecaidine, arecoline, and a few other constituents, reported to be present in Areca catechu were also tested, but none of them were found to inhibit MAO. Present study suggests that the dichloromethane fraction from A. catechu possesses antidepressant property via MAO-A inhibition.

The hexane and aqueous fractions of Areca catechu (A. catechu) have demonstrated anti-depressant properties in screens used to detect such activity. Similar properties had previously been detected in the plant's aqueous ethanolic extract. The aqueous ethanolic extract (F(1)), and the hexane (F(2)) and aqueous (F(5)) fractions inhibit monoamine oxidase (MAO) in rat brain homogenates. The aqueous fraction seems to be the most potent inhibitor of MAO and its effect is similar to that of clorgyline (a specific MAO-A inhibitor). The extract and fractions from A. catechu, therefore, merit further research in the quest for new anti-depressants.

We report on the antidepressant activity in the ethanol extract of Areca catechu. Antidepressant activity was evaluated in rodents using the forced swimming and tail suspension tests. The ethanol extract (4–80 mg/kg) caused a significant reduction in the immobility time without effecting the spontaneous motor activity. Our findings suggest that the ethanol extract possesses antidepressant activities. © 1997 by John Wiley & Sons, Ltd.