- Photochemical transformations of 1-arylcyanomethyl-9,10-anthraquinones
-
Photochemical transformations of 1-arylcyanomethyl-9,10-anthraquinones were studied.It was established that under irradiation, the hydrogen atom of the substituted methyl group is transferred to a peri-quinoid oxygen atom to form the corresponding 9-hydroxy-1,10-anthraquinone-1-arylcyanomethides.Dark transformations of photoinduced quinone-methides result from three competing parallel processes: intramolecular transfer of the hydrogen atom, a reaction with a solvent (alcohol), and oxidation by dissolved oxygen.The kinetics of these reactions were studied. - Keywords: photochemical transformations, 1-arylcyanomethyl-9,10-anthraquinones, nucleophilic addition, oxidation, kinetics, quantum-chemical calculations
- Klimenko, L. S.,Mainagashev, I. Ya.,Leonenko, Z. V.,Gritsan, N. P.
-
-
Read Online
- Synthesis of damnacanthal, a naturally occurring 9,10-anthraquinone and its analogues, and its biological evaluation against five cancer cell lines
-
Damnacanthal and nordamnacanthal, two naturally occurring 9,10-anthraquinones, and their analogues were synthesized. Cytotoxic activity against five cancer cell lines was evaluated using MTT assay. 2-Bromomethyl-1,3-dimethoxyanthraquinone was found to display the highest activity against all cell lines with IC50 range of 2-8 μM. Structure-activity relationship (SAR) assessment was considered to rationalise the cytotoxic effect. Bromomethyl group at position C-2 of the anthraquinone was found to be important in exerting cytotoxic activity of this class of compounds. The presence of the flanking methoxyl or hydroxyl groups at C-1 and C-3 also contributes to this activity. Finally, the antioxidant effect of these compounds was evaluated. MTT assay was used to measure the cytotoxicity against different cancer cell lines. Antioxidant activity was measured by FTC and TBA methods. Only two anthraquinones, damnacanthal and nordamnacanthal, were found to be antioxidative.
- Saha, Koushik,Lam, Kok Wai,Abas, Faridah,Sazali Hamzah,Stanslas, Johnson,Hui, Lim Siang,Lajis, Nordin H.
-
p. 2093 - 2104
(2013/07/26)
-
- Synthesis of new cytotoxic aminoanthraquinone derivatives via nucleophilic substitution reactions
-
Aminoanthraquinones were successfully synthesized via two reaction steps. 1,4-Dihydroxyanthraquinone (1) was first subjected to methylation, reduction and acylation to give an excellent yield of anthracene-1,4-dione (3), 1,4-dimethoxyanthracene- 9,10-dione (5) and 9,10-dioxo-9,10-dihydroanthracene-1, 4-diyl diacetate (7). Treatment of 1, 3, 5 and 7 with BuNH2 in the presence of PhI(OAc)2 as catalyst produced seven aminoanthraquinone derivatives 1a, b, 3a, and 5a-d. Amination of 3 and 5 afforded three new aminoanthraquinones, namely 2-(butylamino)anthracene-1,4-dione (3a), 2-(butylamino)anthracene-9,10-dione (5a) and 2,3-(dibutylamino)anthracene-9,10-dione (5b). All newly synthesised aminoanthraquinones were examined for their cytotoxic activity against MCF-7 (estrogen receptor positive human breast) and Hep-G2 (human hepatocellular liver carcinoma) cancer cells using MTT assay. Aminoanthraquinones 3a, 5a and 5b exhibited strong cytotoxicity towards both cancer cell lines (IC50 1.1-13.0 μg/mL).
- Nor, Siti Mariam Mohd,Sukari, Mohd Aspollah Hj Md,Azziz, Saripah Salbiah Syed Abdul,Fah, Wong Chee,Alimon, Hasimah,Juhan, Siti Fadilah
-
p. 8046 - 8062
(2013/08/23)
-
- Preparation of 3,4-Dihydroanthracen-1(2H)-ones. A Synthetic Approach to Islandicin and Digitopurpone via Difluoro1,O9>boron Chelates
-
Three 9,10-dihydroxyanthracen-1(2H)-one derivatives (2a-c) have been obtained by the catalytic hydrogenation of quinizarin, 1-hydroxy-5-methoxyanthraquinone, and 1-hydroxy-8-methoxyanthraquinone, respectively; in the last two reactions, monohydroxyanthracen-1(2H)-ones (4a) and (4b) are formed as by-products.The anthracenone derivatives (2a-c) were O-methylated by methyl toluene-p-sulphonate and the selective demethylation of the dimethoxy derivative (2d) to the monomethoxy derivative (2e) was effected by AlCl3.The silyl enolate (5) was unreactive toward C-methylation but the lithium enolate of the anthracenone (2d) reacted with methyl iodide to give a mixture of C-mono (2f) and C-di (6a) alkylated derivatives; in contrast, the boron enolate of (2d) reacted with methyl iodide to give exclusively the C-monomethylated derivative (2f) and this procedure was extended to the synthesis of 5-methoxy (2g) and 8-methoxy (2h) analogues of (2f).Whereas the dimethoxyanthracenone derivative (2d) is brominated (Br2-CHCl3, 0 deg C) in separate reactions to give monobromo (2i) and dibromo (6b) derivatives, the difluoroboron chelate (9a) was converted by photochemical bromination into a product (9g) of benzylic substitution; the analogue (9h) was similarly obtained from the difluoroboron chelate (9b).The boron derivatives (9g) and (9h) were transformed by methanol into hydroxydimethoxyanthracenone derivatives (2l) and (2m), and (9g) was also converted by wet alumina into the dihydroxymethoxyanthracenone (2n).The hydroxydimethoxyanthracenone (2l) and (2m) were transformed by 2,3-dichloro-5,6-dicyanobenzoquinone and selenium dioxide into 1-hydroxy-4-methoxyanthraquinone and 1-hydroxy-4-methoxy-2-methylanthraquinone, respectively.
- Preston, Peter N.,Will, Stephen G.,Winwick Thomas,Morley, John O.
-
p. 1001 - 1007
(2007/10/02)
-
- The Regiospecific Preparation of 1,4-Dioxygenated Anthraquinones: A New Route to Islandicin, Digitopurpone, and Madeirin
-
A direct, versatile, one-step synthesis of anthraquinones which exhibits total regioselectivity (>99 percent) and involves the reaction of the anion of 4- or 7-methoxy-3-phenylsulphonylphthalides with variously substituted quinone monoacetals is reported.
- Russell, Richard A.,Warrener, Ronald N.
-
p. 108 - 110
(2007/10/02)
-
- A New Route to Anthraquinones
-
The lithium salts derived from position 3 of phthalides react with arynes to form adducts, which, upon aerial oxidation, produce anthraquinones in moderate to good yields.Substituted phthalides and arynes also participate in this general reaction.The addition to unsymmetrically substituted arynes shows regioselectivity, whilst the availability of a new general route to phthalides extends the scope of this reaction.
- Dodsworth, David J.,Calcagno, Maria-Pia,Ehrmann, E. Ursula,Devadas, Bhatt,Sammes, Peter G.
-
p. 2120 - 2124
(2007/10/02)
-