137494-04-3Relevant articles and documents
Enantioselective separation of 4,8-DHT and phytotoxicity of the enantiomers on various plant species
Yang, Li,Ma, Xiao-Yan,Ruan, Xiao,Jiang, De-An,Pan, Cun-De,Wang, Qiang
, (2016)
As a candidate for bioherbicide, 4,8-dihydroxy-1-tetralone (4,8-DHT) was isolated from Caryospora callicarpa epicarp and its two enantiomers, S-(+)-isosclerone and R-(-)-regiolone, were separated by chiral high-performance liquid chromatography (HPLC) on a Chiralcel OD column with chiral stationary phase (CSP)-coated cellulose-tris(3,5-dimethylphenylcarbamate). Then, the phytotoxicity of 4,8-DHT and its enantiomers toward the seeds germination and seedling growth of the five tested plant species, including lettuce (Latuca sativa), radish (Raphanus sativus), cucumber (Cucumis sativus), onion (Allium cepa), and wheat (Triticum aestivum), were investigated and the results indicated a hormesis at low concentration of 4,8-DHT and its enantiomers, but a retardant effect at high concentration. Between the two enantiomers of 4,8-DHT, the S-(+)-isosclerone was more toxic to seeds germination and seedling growth of the five tested plant species than the R-(-)-regiolone, and also the phytotoxicity of S-(+)-isosclerone varied with different plants. For example, S-(+)-isosclerone was the most active to seedling growth of lettuce, indicating that S-(+)-isosclerone had specific effects on different organisms. Thus, all of the chirality and concentration of 4,8-DHT, as well as the affected plant species, need to be taken into consideration in the development and utilization of 4,8-DHT.
4,8-dihydroxy-1-Tetralone chemical synthesis method
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Paragraph 0020; 0021, (2016/10/08)
The invention discloses a chemical synthesis method of 4,8- dihydroxyl-1-tetralone. The chemical synthesis method comprises the following steps: by taking 5-hydroxyl- tetralone as a raw material, firstly, adding NaBH4 to synthesize 5-hydroxyl-tetralol by taking methanol as a solvent, and adding benzoyl chloride to synthesize 1,5-dibenzoyl- tetrahydronaphthalene by taking pyridine as a solvent; then, adding benzene, diatomite, pyridinium dichromate and tert-butyl hydroperoxide to synthesize 4,8- dibenzoyl-1-tetralone; and finally, adding cesium carbonate to synthesize 4,8- dihydroxyl-1-tetralon by taking methanol as a solvent. The chemical synthesis method disclosed by the invention is simple in process, green and environmentally friendly and high in product purity which reaches 99.82%, and has a reaction total yield of 39-47%.
Unprecedented role of hydronaphthoquinone tautomers in biosynthesis
Husain, Syed Masood,Schaetzle, Michael A.,Luedeke, Steffen,Mueller, Michael
supporting information, p. 9806 - 9811,6 (2015/02/02)
Quinones and hydroquinones are among the most common cellular cofactors, redox mediators, and natural products. Here, we report on the reduction of 2-hydroxynaphthoquinones to the stable 1,4-diketo tautomeric form of hydronaphthoquinones and their further reduction by fungal tetrahydroxynaphthalene reductase. The very high diastereomeric and enantiomeric excess, together with the high yield of cis-3,4-dihydroxy-1-tetralone, exclude an intermediary hydronaphthoquinone. Labeling experiments with NADPH and NADPD corroborated the formation of an unexpected 1,4-diketo tautomeric form of 2-hydroxyhydronaphthoquinone as a stable intermediate. Similar 1,4-diketo tautomers of hydronaphthoquinones were established as products of the NADPH-dependent enzymatic reduction of other 1,4-naphthoquinones, and as substrates for different members of the superfamily of short-chain dehydrogenases. We propose an essential role of hydroquinone diketo tautomers in biosynthesis and detoxification processes.
One-step enantioselective synthesis of (4S)-isosclerone through biotranformation of juglone by an endophytic fungus
Prado, Soizic,Buisson, Didier,Ndoye, Idrissa,Vallet, Marine,Nay, Bastien
, p. 1189 - 1191 (2013/03/28)
We describe here a direct access to (4S)-isosclerone (+)-1, an important structural component of several natural products featuring a spirobisnaphthalene ring system. Starting with the commercially available 5-hydroxy-1,4- naphthalenedione (juglone), biotransformation by the isosclerone-producing endophytic fungus Paraconiothyrium variabile is described. The absolute configuration of (+)-1 was determined unambiguously using circular dichroism and by measurement of the optical rotation. Moreover, the biotransformations of other naphthalene derivatives were undertaken and led to the corresponding (4S)-hydroxy-1-tetralone. At last, this work brings some insights on the biosynthesis of natural tetralones.
Asymmetric synthesis of the cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-ones
Couche, Emmanuel,Fkyerat, Abdellatif,Tabacchi, Raffaele
, p. 210 - 221 (2007/10/03)
A short and efficient protocol for the asymmetric synthesis of cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-one (1 and 2, resp.) is described, with a phthalide annulation as the key step. Introduction of a OH substituent at position 2 was performed by Sharpless dihydroxylation of a silyl enol ether or by means of an N-sulfonyloxaziridine. The absolute configuration of each isomer was determined via Mosherester derivatives. By comparison with previously recorded CD spectra of our natural sample, we established that the natural trans- and cis-isomers from Ceratocystis fimbriata sp. platani were the (-)-(2S,4S)-isomer (-)-2 and the (+)-(2S,4R)-isomer (+)-1, respectively.
The Preussomerins: Novel Antifungal Metabolites from the Coprophilous Fungus Preussia isomera Cain
Weber, Holly A.,Gloer, James B.
, p. 4355 - 4360 (2007/10/02)
Preussomerins A-F (1-6), a series of new aromatic bis-ketals with antifungal and antibacterial activities, have been isolated from the coprophilous fungus Preussia isomera (CBS 415.82).Preussomerins A-F were obtained from ethyl acetate extracts of liquid cultures of P. isomera by silica gel chromatography and reversed-phase HPLC.The structures of preussomerins B-F (2-6) were proposed on the basis of extensive NMR experiments and by comparison with the data for preussomerin A (1), whose structure was confirmed by single-crystal X-ray diffraction analysis.The isolation process was guided by in vitro bioassays for antifungal antagonism toward other coprophilous fungi.
