Isolation of marker compounds from the leaves of adhatoda vasica and their biological activities

Abstract

Acanthaceae family member A. vasica is enhanced with important commercially and biologically active compounds. From the deep interest of these compounds and their biological activities , the leaves of this plants was extracted with Methanol for 24 hours, the extract was filtered and concentrated. Extraction was repeated three times. The concentrated material was treated with 5% acetic acid and warmed for few minute and filtered. The filtrate was defatted with hexane, basified with ammonia(pH 9.0) and then extracted with chloroform to good yield of crude alkaloids. Pure alkaloid (Vasicine and vasicinone ) were obtained by column chromatography over silica gel using Chloroform and Methanol mixtures with increasing polarity. After the end of separating process two compounds were purified and the structure were determined. Among them the compound-1 and compound-2 was isolated from the different portion of chloroform and Methanol mixture parts.

1,2,3,9-Tetrahydropyrrolo[2,1-b]quinazolin-3-ol (Compound-1)

3-hydroxy-2, 3-dihydro-1H-pyrrolo[2,1-b]quinazolin-9-one (Compound -2)

The above structures of the compounds ( 1-2) were elucidated by various spectroscopic methods( UV, IR, 1H-NMR, 13C-NMR, LC-MS) According to the reported literature compound-2 are found to be isolated for the first time from the plant.

The methanol extract was found to have high antibacterial activity whereas, the ethanol extract part showed low antibacterial activity. Thus the isolation, Characterization and investigation of potent biological activity of the crude extracts might generate much synthetic and biological interest in this class of the natural products.