New pregnane-type steroidal alkaloids from Sarcocca saligna and their cholinesterase inhibitory activity

• Published in: Steroids Vol. 69; no. 11-12; p. 735
• Main Authors: Atta-ur-Rahman, Feroz, Fareeda, Naeem, Ismat, Zaheer-ul-Haq, Nawaz, Sarfraz Ahmad, Khan, Naeema, Khan, M Riaz, Choudhary, M Iqbal
• Format: Journal Article
• Language: English
• Published: United States 01.10.2004
• Subjects: Alkaloids - chemistry; Alkaloids - pharmacology; Cholinesterase Inhibitors - chemistry; Cholinesterases - metabolism; Enzyme Inhibitors - pharmacology; Ethanol - pharmacology; Inhibitory Concentration 50; Magnetic Resonance Spectroscopy; Models, Chemical; Plant Extracts; Plants - metabolism; Pregnanes - chemistry; Spectrophotometry; Steroids - chemistry; Steroids - pharmacology; Ultraviolet Rays
• ISSN: 0039-128X; 1878-5867

Five new steroidal alkaloids, 5,14-dehydro-N(a)-demethylsaracodine [3beta-N(a)-methyl-20S-N(b)-acetyl-N(b)-methylamino-pregn-5,14-diene] (1), 14-dehydro-N(a)-demethylsaracodine [3beta-N(a)-methyl-20S-N(b)-acetyl-N(b)-methylamino-5alpha-pregn-14-ene] (2), 16-dehydrosarcorine [(20S)-20-(N,N-dimethylamino)-3beta-(N(a)-acetylamido)-5alpha-pregn-16-ene] (3), 2,3-dehydrosarsalignone [(20S)-20-(N,N-dimethylamino)-3beta-(tigloylamino)-pregn-2,5-diene-4-one] (4), and 14,15-dehydrosarcovagine-D [(20S)-20-(N,N-dimethylamino)-3beta-(tigloylamino)-5alpha-pregn-2,14-diene-4-one] (5), were isolated from the ethanolic extract of Sarcococca saligna, along with two known bases, sarcovagenine-C (6) and salignarine-C (7). Their structures were elucidated on the basis of spectroscopic methods. All seven compounds were found to possess cholinesterase inhibitory potential in a concentration-dependent manner with the IC50 values ranging from 12.5 to 200 microM against acetylcholinesterase and from 1.25 to 32.2 microM against butyrylcholinesterase.