Unexpected reaction of 2-amino-1,4-naphthoquinone with aldehydes: new synthesis of naphtho[2,1-d]oxazole compounds

Aeken, Sam Van; Deblander, Jurgen; Houwer, Johan De; Mosselmans, Timothy; Tehrani, Kourosch Abbaspour

doi:10.1016/j.tet.2010.10.082

Cited by 20 publications

(7 citation statements)

References 39 publications

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“…The reaction itself has been well known for decades, however reports are limited to the synthesis of benzobisoxazoles obtained by reacting two molar equivalents of aldehydes with 2,5-diaminoquinone [32,33], a reaction which was recently employed by the research group of 2016 Nobel laureate Fraser Stoddart in the design of macrocyclic compounds pillar[ n ]arenes [34]. Synthesis of monocyclized products is thus far limited to substructures of extended aromatic systems such as naphthoquinones [35,36], quinolinequinones and indoloquinones [37]. Herein we thus present the novel synthesis of 2-aryl-5-hydroxybenzoxazoles.…”

Section: Resultsmentioning

confidence: 99%

Synthesis, Biological Evaluation and Docking Studies of Benzoxazoles Derived from Thymoquinone

et al. 2018

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Thymoquinone (TQ), a natural compound with antimicrobial and antitumor activity, was used as the starting molecule for the preparation of 3-aminothymoquinone (ATQ) from which ten novel benzoxazole derivatives were prepared and characterized by elemental analysis, IR spectroscopy, mass spectrometry and NMR (1H, 13C) spectroscopy in solution. The crystal structure of 4-methyl-2-phenyl-7-isopropyl-1,3-benzoxazole-5-ol (1a) has been determined by X-ray diffraction. All compounds were tested for their antibacterial, antifungal and antitumor activities. TQ and ATQ showed better antibacterial activity against tested Gram-positive and Gram-negative bacterial strains than benzoxazoles. ATQ had the most potent antifungal effect against Candida albicans, Saccharomyces cerevisiae and Aspergillus brasiliensis. Three benzoxazole derivatives and ATQ showed the highest antitumor activities. The most potent was 2-(4-fluorophenyl)-4-methyl-7-isopropyl-1,3-benzoxazole-5-ol (1f). Western blot analyses have shown that this compound inhibited phosphorylation of protein kinase B (Akt) and Insulin-like Growth Factor-1 Receptor (IGF1R β) in HeLa and HepG2 cells. The least toxic compound against normal fibroblast cells, which maintains similar antitumor activities as TQ, was 2-(4-chlorophenyl)-4-methyl-7-isopropyl-1,3-benzoxazole-5-ol (1e). Docking studies indicated that 1e and 1f have significant effects against selected receptors playing important roles in tumour survival.

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Section: Resultsmentioning

confidence: 99%

Synthesis, Biological Evaluation and Docking Studies of Benzoxazoles Derived from Thymoquinone

et al. 2018

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“…It is well known that there are two isomeric structures of naphthoxazole, one is N atom at C-1 and O atom at C-2 position of naphthyl ring that is formulated as naphtho [1,2-d]oxazole [11], another enantiomer is naphtho [2,1-d] oxazole [12]. In this paper, we obtained X-ray crystallography of compound 2a [13], the structure of naphthoxazole is the latter.…”

Section: Resultsmentioning

confidence: 99%

Copper‐Mediated Addition of Ethanolamine Affording 2‐Hydroxymethyl Naphtho[2,1‐d]oxazoles from 2‐Naphthols

Wang

Yang

2013

Journal of Heterocyclic Chem

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“…Particularly, aminoquinone structures draw interest in the literature because of the similar biological characteristics to quinone moieties (5,23,(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36). Although they have numerous beneficial biological activities, quinone structures including pharmacophore groups could sometimes cause possible toxic effects in in vivo implementations.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterization of New Cyclic Aminobenzoquinones

Tuyun

Yıldız

2018

Journal of the Turkish Chemical Society Section A: Chemistry

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The aim of this research is to synthesize and characterize new members of cyclic aminobenzoquinones. Mono amino substituted products, namely 2-chloro-5,6-dimethyl-3-(pyrrolidin-1-yl)-1,4-benzoquinone (2), 2-chloro-5,6-dimethyl-3-(piperidin-1-yl)-1,4benzoquinone (3), 2-chloro-5,6-dimethyl-3-morpholino-1,4-benzoquinone (4), and 2-chloro-5,6dimethyl-3-thiomorpholino-1,4-benzoquinone (5) have been synthesized by the nucleophilic substitution reactions between 2,3-dichloro-5,6-dimethyl-1,4-benzoquinone (1) and cyclic secondary amines with a green methodology using water as solvent. Structure determination of the new products (2-5) was established on the basis of FTIR, 1 H NMR, 13 C NMR, and mass spectrometry.

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Unexpected reaction of 2-amino-1,4-naphthoquinone with aldehydes: new synthesis of naphtho[2,1-d]oxazole compounds

Cited by 20 publications

References 39 publications

Synthesis, Biological Evaluation and Docking Studies of Benzoxazoles Derived from Thymoquinone

Synthesis, Biological Evaluation and Docking Studies of Benzoxazoles Derived from Thymoquinone

Copper‐Mediated Addition of Ethanolamine Affording 2‐Hydroxymethyl Naphtho[2,1‐d]oxazoles from 2‐Naphthols

Synthesis and Characterization of New Cyclic Aminobenzoquinones

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