1.3.2.NMR based methods: These rely on the ability of NMR-based techniques to resolve signals given by different functional groups within a molecule,or different molecules in a mixture,and help in the rapid identification of functional groups and structural motifs.DEPT,COSY or HSQC spectra are some of them.9.10 1.3.3.Chromatographic methods. Prefractionation methods depend on the ability to selectively remove a few undesirable classes of compounds.Selective removal of tannins by use of polyamide chromatography is one of the most widely used prefractionation-dereplication methods.Sephadex LH-20 and HP20 MCI gelll were been reported to selectively remove tannins from plant extracts.The remaining extract can then be evaluated for bioactivity. 1.3.4.Activity profiling: It is a dereplication method where the bioactivity of an extract is profiled in several different assays.The COMPARE algorithm used with the NCI's sixty-cell line panel is one of the most well-known methods.COMPARE method considers ICso values,which represent the concentration of a compound inhibiting the cell growth by 50%.12 1.4.Biogenesis and classification of natural products: The classification of natural products can be made on the basis of biogenesis where the process of photosynthesis plays a lead role Carbohydrates,the initial products of photosynthesis undergo alterations and leads to the formation of low molecular weight pool of 1.3.2. NMR based methods: These rely on the ability of NMR-based techniques to resolve signals given by different functional groups within a molecule, or different molecules in a mixture, and help in the rapid identification of functional groups and structural motifs. DEPT, COSY or HSQC spectra are some of them.9,10 1.3.3. Chromatographic methods: Prefractionation methods depend on the ability to selectively remove a few undesirable classes of compounds. Selective removal of tannins by use of polyamide chromatography is one of the most widely used prefractionation-dereplication methods. Sephadex LH-20 and HP20 MCI gel11 were been reported to selectively remove tannins from plant extracts. The remaining extract can then be evaluated for bioactivity. 1.3.4. Activity profiling: It is a dereplication method where the bioactivity of an extract is profiled in several different assays. The COMPARE algorithm used with the NCI's sixty-cell line panel is one of the most well-known methods. COMPARE method considers IC50 values, which represent the concentration of a compound inhibiting the cell growth by 50%.12 1.4. Biogenesis and classification of natural products: The classification of natural products can be made on the basis of biogenesis where the process of photosynthesis plays a lead role. Carbohydrates, the initial products of photosynthesis undergo alterations and leads to the formation of low molecular weight pool of