Constituintes químicos e atividade antioxidante de Sida galheirensiS Ulbr. (Malvaceae)

• Main Authors: Davi Antas e Silva, Tânia Maria Sarmento da Silva, Antônio Cláudio da Silva Lins, Danielly Albuquerque da Costa, José Marcílio Sobral Cavalcante, Wemerson Neves Matias, Maria de Fátima Vanderlei de Souza, Raimundo Braz Filho
• Format: Article
• Language: English
• Published: Sociedade Brasileira de Química 2006-12-01
• Series: Química Nova
• Subjects: Sida galheirensis; Malvaceae; flavonoids
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422006000600020&lng=en&tlng=en
• ISSN: 1678-7064

The phytochemical investigation of Sida galheirensis led to the isolation of 5,4'-dihydroxy-3,7,3´-trimethoxyflavone, 17³-ethoxyphaeoforbide, a rare natural product, 6,7-dimethoxycoumarin, ortho-hydroxybenzoic acid, sitosterol-3-O-beta-D-glucopyranoside, stigmasterol-3-O-beta-D-glucopyranoside, 5,7,4'-trihydroxyflavone, 5,7,3',4'-tetrahydroxyflavone, kaempferol-3-O-beta-D-(6"-E-p-coumaroyl) glucopyranoside and luteolin 7-O-beta-D-glucopyranoside. Their structures were assigned based on spectroscopic analyses, including two-dimensional NMR techniques. Antioxidant activities of hexane, CHCl3, EtOAc, BuOH and EtOH extracts of Sida galheirensis were measured using the 1,2-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging assay. This is also the first work reporting the chemical investigation of Sida galheirensis.