关键词: 萘醌P, 紫草, 苯胺, 硫酚, 亲核反应, 生物活性, 迈克尔加成反应, 氧化, 广东省自然科学基金

Seven new naphthazarin derivatives were synthesized using the reactions of isolated β,β-dimethylacrylalkannin with aniline and thiophenol. β,β-dimethylacrylalkannin 1, a naphthazarin compound isolated from the root of Arnebia euchroma, reacts with aniline to afford oxidative Michael addition products 2 and 3. Compound 1 reacts with aniline in the presence of NaBH~4 or with thiophenol to give the products 4,5,6a～6c. The ^1H, ^1^3C NMR spectra of the products show that the hydrogen atom on 6-C or 7-C and the ester grorp on 1'-C of 1 are replaced by nucleophiles. It is concluded that nucleophiles add to the side chain (1'-C) by an reductive alkylation and to the quinone ring (6-c or 7-C) by an oxidative Michael addition. The cytotoxic activities of the natural and synthetic compounds were investigated.

Key words: NAPHTHQUINONE P, LITHOSPERMUM ERYTHRORRHIZON, ANILINE, THIOPHENOLS, NUCLEOPHILIC REACTION, BIOLOGICAL ACTIVITY, MICHAEL ADDITION REACTION, OXIDATION