New Cholinesterase‐Inhibiting Steroidal Alkaloids from <i>Sarcococca saligna</i>

Abstract

Abstract Seven new steroidal alkaloids, 2‐hydroxysalignarine‐E (=(2′ E ,20 S )‐20‐(dimethylamino)‐2 β ‐hydroxy‐3 β ‐(tigloylamino)pregn‐4‐ene; 1 ), 5,6‐dihydrosarconidine (=(20 S )‐20‐(dimethylamino)‐3 β ‐(methylamino)‐5 α ‐pregn‐16‐ene; 2 ), salignamine (=(20 S )‐20‐(methylamino)‐3 β ‐methoxypregna‐5,16‐diene; 3 ), 2‐hydroxysalignamine (=(20 S )‐20‐(dimethylamino)‐2 β ‐hydroxy‐3 β ‐methoxypregna‐5,16‐diene; 4 ), salignarine‐F (=(2′ E , 20 S )‐20‐(dimethylamino)‐4 β ‐hydroxy‐3 β ‐(tigloylamino)pregn‐5‐ene; 5 ), salonine‐C (=(2′ E ,20 S )‐20‐(dimethylamino)‐3 β ‐(tigloylamino)pregna‐4,14‐diene; 6 ), and N ‐[formyl(methyl)amino]salonine‐B (=(20 S )‐20‐[formyl(methyl)amino]‐3 β ‐methoxypregna‐5,16‐diene; 7 ) have been isolated from the MeOH extract of Sarcococca saligna , along with the six known alkaloids dictyophlebine ( 8 ), epipachysamine‐D ( 9 ), saracosine ( 10 ), iso‐ N ‐formylchonemorphine ( 11 ), sarcodinine ( 12 ), and alkaloid‐C ( 13 ). The structures of 1 – 7 were deduced from spectral data. Compounds 1 – 13 demonstrated significant activity against acetyl‐ and butyrylcholinesterase.