ABSTRACT
Twelve chlorogenic acid derivatives and two flavones were isolated from Moquiniastrum floribundum (Asteraceae, other name: Gochnatia floribunda). Compounds were evaluated in relation to their cytotoxicity and antiradical properties. Cytotoxicity was not observed for compounds, however, chlorogenic acid derivatives showed antiradical activity and were more active than the Trolox standard. Quinic acid esterified with caffeoyl group at C-4 position showed higher antiradical activity compared to acylation at C-3 or C-5 positions. Additional caffeoyl groups esterified in quinic acid increase the antiradical activity observed for 4-caffeoylquinic acid. Excepted to 3,4-dicaffeoylquinic acid methyl ester, methyl ester derivatives show higher capacity of trapping radicals than their respective acids. Consequently, the presence of caffeoyl group at C-4 position of quinic acid is suggested as fundamental to obtain the highest antiradical activity.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Antioxidants/pharmacology , Asteraceae/chemistry , Biphenyl Compounds/antagonists & inhibitors , Picrates/antagonists & inhibitors , Quinic Acid/analogs & derivatives , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Antioxidants/chemistry , Antioxidants/isolation & purification , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , HCT116 Cells , Humans , Molecular Structure , Quinic Acid/chemistry , Quinic Acid/isolation & purification , Quinic Acid/pharmacology , Structure-Activity RelationshipABSTRACT
A synthetic method to obtain α- and ß-pyran naphthoquinones 10 and 11 with a hydroxyl substituent on the aromatic ring was developed. Two series of α- and ß-pyran naphthoquinones were obtained from the 8-hydroxy-lawsone, and their anticancer properties were evaluated against four tumor cell lines. In general, the new compounds displayed good activity, possibly indicating that these compounds have increased pro-oxidant capacity. The 9-hydroxy-α-lapachone and 7-hydroxy-ß-lapachone analogues of the natural products α-lapachone and ß-lapachone were successfully produced by this methodology.
