- Triflic acid an efficient catalyst for the Thiele-Winter reaction
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Triflic acid is a convenient and non hazardous acid for the Thiele-Winter reaction of quinones. The synthetic scope of the Thiele-Winter reaction was increased by the use of triflic acid.
- Villemin, Didier,Bar, Nathalie,Hammadi, Mohamed
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- Bi(OTf)3-catalyzed acylation of p-quinones: A facile synthesis of acylated hydroquinones
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p-Quinones undergo smooth acylation with acetic anhydride in the presence of 2mol% of bismuth triflate under mild conditions to afford the corresponding 1,4-diacylated-2-acetoxylated hydroquinones in excellent yields with high selectivity.
- Yadav,Reddy, B. V. Subba,Swamy,Rao, K. Raghavender
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- Discovery of juglone and its derivatives as potent SARS-CoV-2 main proteinase inhibitors
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SARS-CoV-2 as a positive-sense single-stranded RNA coronavirus caused the global outbreak of COVID-19. The main protease (Mpro) of the virus as the major enzyme processing viral polyproteins contributed to the replication and transcription of SARS-CoV-2 in host cells, and has been characterized as an attractive target in drug discovery. Herein, a set of 1,4-naphthoquinones with juglone skeleton were prepared and evaluated for the inhibitory efficacy against SARS-CoV-2 Mpro. More than half of the tested naphthoquinones could effectively inhibit the target enzyme with an inhibition rate of more than 90% at the concentration of 10 μM. In the structure-activity relationships (SARs) analysis, the characteristics of substituents and their position on juglone core scaffold were recognized as key ingredients for enzyme inhibitory activity. The most active compound, 2-acetyl-8-methoxy-1,4-naphthoquinone (15), which exhibited much higher potency in enzyme inhibitions than shikonin as the positive control, displayed an IC50 value of 72.07 ± 4.84 nM towards Mpro-mediated hydrolysis of the fluorescently labeled peptide. It fit well into the active site cavity of the enzyme by forming hydrogen bonds with adjacent amino acid residues in molecular docking studies. The results from in vitro antiviral activity evaluation demonstrated that the most potent Mpro inhibitor could significantly suppress the replication of SARS-CoV-2 in Vero E6 cells within the low micromolar concentrations, with its EC50 value of about 4.55 μM. It was non-toxic towards the host Vero E6 cells under tested concentrations. The present research work implied that juglone skeleton could be a primary template for the development of potent Mpro inhibitors.
- Cui, Jiahua,Jia, Jinping
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supporting information
(2021/08/25)
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- Design, synthesis and activity of BBI608 derivatives targeting on stem cells
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STAT3 plays a vital role in maintaining the self-renewal of tumor stem cells. BBI608, a small molecule identified by its ability to inhibit gene transcription driven by STAT3 and cancer stemness properties, can inhibit stemness gene expression and kill stemness-high cancer cells isolated from a variety of cancer types. In order to improve the pharmacokinetic properties of BBI608 and the antitumor activity, a series of BBI608 derivatives were designed and synthesized here. Most of these compounds were more potent than BBI608 on HepG2 cells, compound LD-8 had the most potent inhibitory activity among them and was 5.4-fold more potent than BBI608 (IC50 = 11.2 μM), but had considerable activity on normal liver cells L-02. Compounds LD-17 (IC50 = 3.5 μM) and LD-19 (IC50 = 2.9 μM) were found to possess significant inhibitory activities and good selectivity. The results showed that compound LD-19 was worthy to investigate further as a lead compound according to its potent inhibitory activity, ideal ClogP value and better water solubility.
- Zhou, Qifan,Peng, Chen,Du, Fangyu,Zhou, Linbo,Shi, Yajie,Du, Yang,Liu, Dongdong,Sun, Wenjiao,Zhang, Meixia,Chen, Guoliang
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- BBI608 derivative as well as preparation and application thereof
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The invention belongs to the technical field of medicines, and relates to a BBI608 derivative and application of the BBI608 derivative in an anti-tumor medicine. The structures of the derivative and apharmacologically acceptable salt are as follows: as shown in the specification, wherein X, R1, R2 and R3 are as described in claims and the specification. The derivative and the pharmacologically acceptable salt can be used for preparing the anti-tumor medicine, particularly a medicine for treating the stomach cancer (including gastric esophageal cancer) and the pancreatic cancer. An HepG2 cellactivity research finds that the cell inhibition activities of most compounds are obviously higher than that of the anti-tumor medicine BBI608.(Refer to Specification).
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Paragraph 0092; 0093
(2018/05/16)
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- Naphthalene anti-psoriatic agents
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Psoriasis in mammals is relieved by topically administering naphthalenes of the formula: STR1 wherein: R1 is alkoxy, alkylthio, optionally substituted phenoxy or optionally substituted phenylthio; R2 is hydrogen, lower alkyl, optionally substituted phenyl or optionally substituted phenylalkyl; R3 is lower alkyl, lower alkoxy, or halo and m is 0, 1 or 2, or R3 is optionally substituted phenyl, optionally substituted phenyl lower alkyl, optionally substituted phenyl lower alkoxy, amino, lower alkylamino, lower dialkylamino, cyano, or S(0)n R wherein R is lower alkyl; optionally substituted phenyl; optionally substituted phenyl lower alkyl; or optionally substituted heterocyclic aryl of three to nine ring atoms containing one or two heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur, and the pharmaceutically acceptable acid addition salts thereof; and m is 1 and n is 0, 1 or 2; and W is alkyl of one to seven carbon atoms, optionally substituted phenyl or optionally substituted benzyl.
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- cyclo-Trimerisation of 1,4-Naphthoquinone; Cooperation of Phenol/Quinone Additions and Redox Reactions
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The reaction course postulated for the cyclo-trimerisation of 1,4-naphthoquinone (1a) to cyclo-tri-1,4-naphthoquinone (11a) is confirmed and supplemented by: (i) isolation of the red intermediate 1',4'-dihydroxy-2,2'-binaphthyl-1,4-quinone (5a), (ii) synthesis of 11a starting from 5a or 2,2'-binaphthyl-1,4:1'4'-diquinone (6a), and (iii) reduction of 5a and 6a by 1,4-naphthalenediol (2a) to 2,2'-binaphthyl-1,1',4,4'-tetrol (4a).Requirement for the cyclo-trimerisation of 1a to 11a is a cooperation of phenol/quinone additions and redox reactions controlled by the permanent decreasing oxidation potential of the reaction mixture.As byproducts of the synthesis of 11a in acetic acid 9a, 10a, 12a, 12c, 13a, 13c, and 14a could be isolated as acetates.
- Brockmann, Hans
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- The Oxidation of Some Naphthols with Benzoyl Peroxide
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The reactions of four naphthols (1-naphthol (1), 2-naphthol (2), 4-isopropyl-1-naphthol (18), and 3-isopropyl-2-naphthol (19)) with benzoyl peroxide were examined under two reaction conditions (A and B).Each of the naphthols 1,2,18, and 19 was oxidized wi
- Matsumoto, Takashi,Imai, Sachihiko,Yamamoto, Naoya
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p. 911 - 920
(2007/10/02)
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