Abstract
Five new steroidal alkaloids, 5,14-dehydro-
N
a-demethylsaracodine [3β-
N
a-methyl-20
S-
N
b-acetyl-
N
b-methylamino-pregn-5,14-diene] (
1), 14-dehydro-
N
a-demethylsaracodine [3β-
N
a-methyl-20
S-
N
b-acetyl-
N
b-methylamino-5α-pregn-14-ene] (
2), 16-dehydrosarcorine [(20
S)-20-(
N,
N-dimethylamino)-3β-(
N
a-acetylamido)-5α-pregn-16-ene] (
3), 2,3-dehydrosarsalignone [(20
S)-20-(
N,
N-dimethylamino)-3β-(tigloylamino)-pregn-2,5-diene-4-one] (
4), and 14,15-dehydrosarcovagine-D [(20
S)-20-(
N,
N-dimethylamino)-3β-(tigloylamino)-5α-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 IC
50 values ranging from 12.5 to 200
μM against acetylcholinesterase and from 1.25 to 32.2
μM against butyrylcholinesterase.