4707-33-9Relevant articles and documents
Photoconversion of β-Lapachone to α-Lapachone via a Protonation-Assisted Singlet Excited State Pathway in Aqueous Solution: A Time-Resolved Spectroscopic Study
Du, Lili,Li, Ming-De,Zhang, Yanfeng,Xue, Jiadan,Zhang, Xiting,Zhu, Ruixue,Cheng, Shun Cheung,Li, Xuechen,Phillips, David Lee
, p. 7340 - 7350 (2015)
The photophysical and photochemical reactions of β-lapachone were studied using femtosecond transient absorption, nanosecond transient absorption, and nanosecond time-resolved resonance Raman spectroscopy techniques and density functional theory calculations. In acetonitrile, β-lapachone underwent an efficient intersystem crossing to form the triplet state of β-lapachone. However, in water-rich solutions, the singlet state of β-lapachone was predominantly quenched by the photoinduced protonation of the carbonyl group at the β position (O9). After protonation, a series of fast reaction steps occurred to eventually generate the triplet state α-lapachone intermediate. This triplet state of α-lapachone then underwent intersystem crossing to produce the ground singlet state of α-lapachone as the final product. 1,2-Naphthoquinone is examined in acetonitrile and water solutions in order to elucidate the important roles that water and the pyran ring play during the photoconversion from β-lapachone to α-lapachone. β-Lapachone can also be converted to α-lapachone in the ground state when a strong acid is added to an aqueous solution. Our investigation indicates that β-lapachone can be converted to α-lapachone by photoconversion in aqueous solutions by a protonation-assisted singlet excited state reaction or by an acid-assisted ground state reaction.
Naphthoquinone-based hydrazone hybrids: Synthesis and potent activity against cancer cell lines
Gonsalves, Arlan de Assis,Pessoa, Claudia,Silva, Maria Francilene Souza,Silva, Thaissa Lucio,Araújo, Cle?nia Roberta Melo,Araújo, Edigênia Cavalcante,Goulart, Marília Oliveira Fonseca,Guimar?es, Délis Galv?o,Rolim, Larissa Araújo,Santos, Danyelle Candido,Santos, Victória Laysna Dos Anjos,da Costa, Marcília Pinheiro,de Oliveira, Fátima de Cássia Evangelista
, p. 945 - 955 (2021/11/30)
Background: Natural naphthoquinones have shown diversified biological activities including antibacterial, antifungal, antimalarial, and cytotoxic activities. However, they are also compounds with acute cytotoxicity, immunotoxicity, carcinogenesis, and cardio-and hepatotoxicity, and the modification at their redox center is an interesting strategy to overcome such harmful activity. Objective: In this study, four novel semisynthetic hydrazones, derived from the isomers α-and βlapachones (α and β, respectively) and coupled with the drugs hydralazine (HDZ) and isoniazid (ACIL), were prepared, evaluated by electrochemical methods and assayed for anticancer activity. Methods: The semisynthetic hydrazones were obtained and had their molecular structures established by NMR, IR, and MS. Anticancer activity was evaluated by cell viability determined by reduction of 3-(4,5-dimethyl-2-thiazol)-2,5-diphenyl-2H-tetrazolium bromide (MTT). The electrochemical studies, mainly cyclic voltammetry, were performed, in aprotic and protic media. Results: The study showed that the compounds 2, 3, and 4 were active against at least one of the cancer cell lines evaluated, compounds 3 and 4 being the most cytotoxic. Toward HL-60 cells, compound 3 was 20x more active than β-lapachone, and 3x more cytotoxic than doxorubicin. Furthermore, 3 showed an SI value of 39.62 for HL-60 cells. Compound 4 was active against all cancer cells tested, with IC50 values in the range 2.90–12.40 μM. Electrochemical studies revealed a profile typical of self-protonation and reductive cleavage, dependent on the supporting electrolyte. Conclusion: These results therefore indicate that compounds 3 and 4 are strong candidates as prototypes of new antineoplastic drugs.
Ligand-based design, synthesis and biochemical evaluation of potent and selective inhibitors of Schistosoma mansoni dihydroorotate dehydrogenase
Calil, Felipe A.,David, Juliana S.,Chiappetta, Estela R.C.,Fumagalli, Fernando,Mello, Rodrigo B.,Leite, Franco H.A.,Castilho, Marcelo S.,Emery, Flavio S.,Nonato, M.Cristina
, p. 357 - 366 (2019/02/19)
Schistosomiasis ranks second only to malaria as the most common parasitic disease worldwide. 700 million people are at risk and 240 million are already infected. Praziquantel is the anthelmintic of choice but decreasing efficacy has already been documented. In this work, we exploited the inhibition of Schistosoma mansoni dihydroorotate dehydrogenase (SmDHODH) as a strategy to develop new therapeutics to fight schistosomiasis. A series of quinones (atovaquone derivatives and precursors) was evaluated regarding potency and selectivity against both SmDHODH and human DHODH. The best compound identified is 17 (2-hydroxy-3-isopentylnaphthalene-1,4-dione) with IC50 = 23 ± 4 nM and selectivity index of 30.83. Some of the new compounds are useful pharmacological tools and represent new lead structures for further optimization.
Ruthenium-catalyzed C-H oxygenation of quinones by weak O-coordination for potent trypanocidal agents
Dias, Gleiston G.,Rogge, Torben,Kuniyil, Rositha,Jacob, Claus,Menna-Barreto, Rubem F. S.,Da Silva Júnior, Eufranio N.,Ackermann, Lutz
supporting information, p. 12840 - 12843 (2018/11/30)
Ruthenium-catalysis enabled the C-5 selective C-H oxygenation of naphthoquinones, and also sets the stage for the site-selective introduction of a hydroxyl group into anthraquinones. A-ring modified naphthoquinoidal compounds represent an important class of bioactive quinones for which the present study encompasses the first C-H oxygenation strategy by weak O-coordination.