Choudhary Muhammad Iqbal, Yousuf Sammer, Nawaz Sarfraz Ahmad, Ahmed Shakil
H.E.J. Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi-75270, Pakistan.
Chem Pharm Bull (Tokyo). 2004 Nov;52(11):1358-61. doi: 10.1248/cpb.52.1358.
A total of two new (1, 2) and four known (3-6) withanolides were isolated from the whole plant of Withania somnifera. Their structures were elucidated on the basis of spectroscopic techniques and were characterized as 6alpha,7alpha-epoxy-3beta,5alpha,20beta-trihydroxy-1-oxowitha-24-enolide (1), 5beta,6beta-epoxy-4beta,17alpha,27-trihydroxy-1-oxowitha-2,24-dienolide (2), withaferin-A (3), 2,3-dihydrowithaferin-A (4), 6alpha,7alpha-epoxy-5alpha,20beta-dihydroxy-1-oxowitha-2,24-dienolide (5), and 5beta,6beta-epoxy-4beta-hydroxy-1-oxowitha-2,14,24-trienolide (6), respectively. Compounds 2, 3, 5, and 6 displayed inhibitory potential against butyrylcholinesterase, but only compounds 3, 4, and 6 were found to be active against acetylcholinesterase.
从睡茄全株中总共分离出两种新的（1, 2）和四种已知的（3 - 6）睡茄内酯。基于光谱技术阐明了它们的结构，并分别将其表征为6α,7α - 环氧 - 3β,5α,20β - 三羟基 - 1 - 氧代 - 威 - 24 - 烯醇内酯（1）、5β,6β - 环氧 - 4β,17α,27 - 三羟基 - 1 - 氧代 - 威 - 2,24 - 二烯醇内酯（2）、睡茄素A（3）、2,3 - 二氢睡茄素A（4）、6α,7α - 环氧 - 5α,20β - 二羟基 - 1 - 氧代 - 威 - 2,24 - 二烯醇内酯（5）和5β,6β - 环氧 - 4β - 羟基 - 1 - 氧代 - 威 - 2,14,24 - 三烯醇内酯（6）。化合物2、3、5和6对丁酰胆碱酯酶显示出抑制潜力，但仅发现化合物3、4和6对乙酰胆碱酯酶有活性。
