80931-34-6Relevant academic research and scientific papers
Concise synthesis of heterocycle-fused naphthoquinones by employing sonogashira coupling and tandem addition-elimination/intramolecular cyclization
Ueda, Kazunori,Yamashita, Mitsuaki,Sakaguchi, Koichi,Tokuda, Harukuni,Iida, Akira
, p. 648 - 654 (2013/07/11)
A concise method for the synthesis of heterocycle-fused naphthoquinones such as naphtho[2,3-b]-furan-4,9-dione, 1H-benz[f]indole-4,9-dione, and naphtho[2,3-b]thiophene-4,9-dione was developed. This method employed Sonogashira coupling and tandem addition-
Synthesis and evaluation of bioactive naphthoquinones from the Brazilian medicinal plant, Tabebuia avellanedae
Yamashita, Mitsuaki,Kaneko, Masafumi,Tokuda, Harukuni,Nishimura, Katsumi,Kumeda, Yuko,Iida, Akira
experimental part, p. 6286 - 6291 (2011/02/26)
A series of naphthoquinones based on the naphtho[2,3-b]furan-4,9-dione skeleton such as (-)-5-hydroxy-2-(1′-hydoxyethyl)naphtho[2,3-b]furan-4,9-dione (1) and its positional isomer, (-)-8-hydroxy-2-(1′-hydoxyethyl)naphtho[2,3-b]furan-4,9-dione (2), which are secondary metabolites found in the inner bark of Tabebuia avellanedae, were stereoselectively synthesized and their biological activities were evaluated in conjunction with those of their corresponding enantiomers. Compound 1 exhibited potent antiproliferative effect against several human tumor cell lines, but its effect against some human normal cell lines was much lower than that of mitomycin. On the other hand, its enantiomer (R)-1 was less active toward the above tumor cell lines than 1. The antiproliferative effect of 2 against all tumor cell lines was significantly reduced. These results indicated the presence of the phenolic hydroxy group at C-5 is of great important for increasing antiproliferative effect. In addition, 1 also showed higher cancer chemopreventive activity than 2, while there were no significant differences between 1 and 2 in antimicrobial activity. Both compounds displayed modest antifungal and antibacterial activity (Gram-positive bacteria), whereas they were inactive against Gram-negative bacteria.
Studies on the Structure and Stereochemistry of Cytotoxic Furanonaphthoquinones from Tabebuia impetiginosa: 5- and 8-Hydroxy-2-(1-hydroxyethyl)naphthofuran-4,9-diones
Fujimoto, Yoshinori,Eguchi, Tadashi,Murasaki, Chikako,Ohashi, Yuji,Kakinuma, Katsumi,et al.
, p. 2323 - 2327 (2007/10/02)
Chemical investigation of the bark of Tabebuia impetiginosa (Bignoniaceae) afforded cytotoxic furanonaphthoquinones, including 5-hydroxy-2-(1-hydroxyethyl)naphthofuran-4,9-dione and its 8-hydroxy isomer.The position of the phenolic group in these two compounds was established by X-ray crystallography.The furanonaphthoquinones were found to be mixtures of both enantiomers in different proportions, i.e., (for the 5-hydroxy isomer) R:S 1:23 and (for the 8-hydroxy isomer) R:S 3:1.The synthesis of the racemic naphthofurans, their optical resolution into enantiomerically pure forms, and the determination of their absolute stereochemistry are described.The structure of kigelinone was also established to be that of the 5-hydroxy isomer, not the 8-hydroxy one, through this study.
