Synthesis and sedative-hypnotic activity of helicid derivatives containing a 1,4-dihydropyridine moiety.

Reactions of natural helicid with a number of 1,3-dicarbonyl compounds or β-ketoester in the presence of ammonium acetate or 1-naphthylamine gave a series of helicid derivatives containing a 1,4-dihydropyridine fragment ( 2a-2h). Eight novel helicid derivatives were structurally confirmed by IR, H NMR, C NMR, and HR-MS spectroscopy and evaluated for their sedative-hypnotic activities on mice. The results demonstrated that two compounds had higher sedative-hypnotic activity compared with helicid. [ABSTRACT FROM AUTHOR]