Part A: Bioassay-guided isolation of cholinesterase inhibiting pregnane-type steroidal alkaloids from sarcococca saligna (D. Don.) Muell., afforded nine new and ten known pregnane-type steroidal alkaloids from the chloroform extract of the plant. The cholinesterase inhibiting of these compounds were carried out by Mr. Sarfraz Ahmad Nawaz in the Enzyme inhibition Laboratory of the Institute.
All compounds were found to possess a varying degree of cholinesterase inhibitory potential in a concentration-dependent manner with the IC50 values ranging from 12.5-200 um against acetylcholinesterae and 1.25-25.0 um against butyryl- cholinesterase
New Alkaloids Isolated from Sarcococca Saligna.
Known Alkaloids Isolated from Sarcococca Saligna.
Part B: The part B of the thesis contains of the bioassay-guided isolation of five antileishmanial constituents from Ficus religiosa Linn, for the first time from this species. Known compounds Isolated from Ficus religiosa.
Subfractions of the plant pure compounds were evaluated for antileishmanial activity by Mrs. Farhana Khukab in the bioassay section of the Institute.
Part C: part c focuses on the synthesis of the fused heterocyclic ring with quinoxaline and benzimidazole moieties, accomplished on the basis of our previously reported arrangement of anthranilopapavarine and B-carbline systems, either by thermolysis or pyrolysis.
The structures of compounds isolated from the sarcococca saligna and Ficus religiosa were elucidated through spectroscopic methods using UV, 1H-and 13 C-NMR and 2D-NMR techniques (COSY, NOESY, NOE, HMQC). Spectroscopic techniques were also employed for the structural identification of synthetic compounds.