Absolute configuration of teucrin-A
ConclusionsThe absolute configuration of teucrin-A, a norditerpenoid fromTeucrium chamaedrys L. has been shown.
Circular dichroism of some steroidal α-ketols and their acetates
Abstract An examination of the CD spectra of certain steroidal α-ketols and their acetates revealed instances where the Cotton effect of the ketone n → π * transition does not obey the octant rule. This was discussed in terms of the conformational preferences of the α-substituents. The relevance of these results to earlier configurational assignments on A-ring α-ketols in the cucurbitacin series was assessed.
Improvement of scopolamine-induced memory impairment by Z-ajoene in the water maze in mice
Z-ajoene, a major compound containing sulfur in oil-macerated garlic products, exhibited inhibitory effects against scopolamine-induced memory impairment in mice using the Morris water maze test. The effects of Z-ajoene were observed dose-dependently (0.25-25 mg/kg). At the highest dosage, the memory performance of mice was improved compared to normal mice. The acetylcholinesterase (AChE) activity in the brain was reduced by administration of Z-ajoene dose-dependently. However, alliin and diallyl disulfide, organosulfur compounds from garlic, did not improve memory performance nor AChE inhibitory effect. These results suggest that Z-ajoene may act on the cholinergic system and on memory impairment caused by excess activity of AChE.