RESUMO
Sulfonylaniline motif plays an important role in pharmaceutical sciences. Developed methods towards this structure are typically lack of good modifiability and stability. In this study, visible-light-mediated sulfonylation of aniline using sulfonyl fluoride as a modifiable and stable sulfonylation reagent is described. A variety of substituted sulfonylanilines were synthesized under mild reaction conditions with moderate to good efficiency. The example of late-stage sulfonylation highlighted the advantage of using sulfonyl fluoride as a sulfonylation reagent. In addition, the crucial influence of counterions on the photocatalyst observed in this system would inspire further research on the photochemistry of sulfonyl fluoride.
RESUMO
OBJECTIVE: To study the chemical constituents of the leaves of Liquidambarformosana. METHODS: The chemical constituents were isolated and purified by column chromatography on silicagel, Sephadex LH-20 and MPLC. Their structures were elucidated on the basis of physicochemical properties and special analysis. RESULTS: Eight compounds were isolated from the leaves of Liquidambar formosana, whose structures were elucidated as gallic acid (1), p-hydroxy-benzoic acid (2), 3-methoxy-4-hydroxy-benzoic acid (3), 3,5-dihydroxy-4-methoxy-benzoic acid (4) kaempferol (5), 3,4-dihydroxy-benzoic acid (6), 3,4-dihydroxy-5-methoxy-benzoic acid (7) and 3ß,23,29-trihydroxy-olean-12-en-28-oic acid-ß-D-glucopyranosyl ester (8). CONCLUSION: Compounds 1-8 are isolated from the leaves of Liquidambar formosana for the first time.
Assuntos
Liquidambar/química , Compostos Fitoquímicos/química , Folhas de Planta/química , Benzoatos/química , Benzoatos/isolamento & purificação , Ésteres/química , Ésteres/isolamento & purificação , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Quempferóis/química , Quempferóis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificaçãoRESUMO
OBJECTIVE: To study the chemical constituents of the leaf of Salix matsudana. METHODS: The chemical constituents were isolated by column chromatography on silica gel, Sephadex LH-20 and MPLC. Their structures were elucidated on the basis of spectral analysis. RESULTS: Eight compounds were isolated and their structures were identified as beta-Sitosterol(1),5,7-Dihydroxychromone-7-O-beta-D-glucopyranoside(2), (2S)-Helichrysin A(3), (2R)-Helichrysin A(4), Luteolin-7-O-beta-D-glucoside(5), Salicin(6), Apigenin-7-O-beta-D-glucopyranside(7), Lutelion-3'-methylether-7-O-f-D-glucopyranside(8). CONCLUSION: Compounds 1-4 are isolated from this plant for the first time.