Microbiological transformation products of 1,6-dimethylnaphthalene

Conclusions 6-Methyl-1-hydroxymethylnaphthalene, 6-methyl-1-naphthoic acid, and 6-hydroxymethyl-1-naphthoic acid were isolated and identified as being the microbiological transformation products of 1,6-dimethyl-naphthalene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2619–2621, November, 1976.     

Fluorescence of zirconium-naphthalene complexes: effect of ortho-naphthalene substitution

The effect of the position of substituents on the formation of metal-naphthalene complexes has been investigated. Two positional isomers, 1-hydroxy-2-naphthoic acid (1H2NA) and 3-hydroxy-2-naphthoic acid (3H2NA), have been chosen. A comparative study of the luminescence behaviour of the two isomers in the presence of Zr(IV) has been performed. Interesting results were obtained. While 1-hydroxy-2-naphthoic acid is quenched in the presence of Zr(IV), 3-hydroxy-2-naphthoic acid produced high-fluorescence enhancement. Several pH studies were performed between pH 2.5 and 5.0 and the stoichiometries of the complexes were also established at the different pH values tested, by use of the Benesi-Hildebrand method. In addition, the formation constants have been calculated. Finally, quenching and lifetime studies were performed in an attempt to establish the type of quenching (static or dynamic) that is produced when a complex is formed between 1-hydroxy-2-naphthoic acid and zirconium metal ion.     

Identification and quantification of polar naphthalene derivatives in contaminated groundwater of a former gas plant site by liquid chromatography-electrospray ionization tandem mass spectrometry

A liquid chromatography (LC) method followed by electrospray ionization (ESI) and tandem mass spectrometry (MS-MS) was developed for the quantification of acidic naphthalene derivatives in the concentration range 0.1 to 100 microg/l without excessive sample preparation. For optimal sensitivity the LC-MS-MS measurements were performed recording mass fragmentation by collision induced dissociation in the multiple reaction mode. The collision energy was optimized for every analyte. The matrix effects of the sample were investigated by spiking standards of 1-naphthoic acid with humic acid (HA) and with calcium chloride. While HA decreased the signal intensity an increase was observed in the presence of calcium chloride. For the investigated groundwater samples of a tar oil contaminated site a complete separation of the analytes from the sample matrix by reversed-phase separation could be obtained. The absence of matrix effects on quantification results was confirmed by comparison of results based on external calibration with those based on standard addition of the analytes to a groundwater sample. In four groundwater samples of the contaminated site naphthalene derivatives like 1-naphthoic acid, 2-naphthoic acid, 1-naphthylacetic acid, 2-naphthylacetic acid, 1-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid, and naphthyl-2-methylenesuccinic acid have been detected.     

Zur Synthese sulfonierter Derivate von 4-Fluoranilin

Syntheses of Sulfonated Derivatives of 4-Fluoroaniline Synthesis of 2-amino-5-fluorobenzenesulfonic acid ( 2 ) was achieved by baking the hydrogen sulfate of 4-fluoroaniline ( 1 ). Sulfonation of p-fluoroacetanilide ( 4 ) with oleum followed by hydrolysis gave 5-amino-2-fluorobenzenesulfonic acid ( 3 ). The same reaction with 1 yielded 3 in an impure state. The structures of 2 and 3 were confirmed by converting the diazonium chlorides derived from 5-fluoro-2-nitroaniline ( 5 ) and from 2-fluofo-5-nitroaniline ( 8 ) to 5-fluoro-2-nitrobenzene-sulfonyl chloride ( 6 ) and 2-fluoro-5-nitrobenzenesulfonyl chloride ( 9 ), respectively, followed by hydrolysis of 6 to 5-fluoro-2-nitrobenzenesulfonic acid ( 7 ), and of 9 to 2-fluoro-5-nitrobenzenesulfonic acid ( 10 ), and by final reduction. Compound 10 was also obtained by sulfonation of 1-fluoro-4-nitrobenzene ( 11 ) with oleum.     

One-pot three-component reaction for the synthesis of novel series of fully substituted 1,3,4-oxadiazole derivatives bearing pyridine moiety

(N-isocyanimino)triphenylphosphorane, 2-pyridinecarbaldehyde, and aromatic carboxylic acids (benzoic acid, 3-methylbenzoic acid, 4-methylbenzoic acid, 3-methoxybenzoic acid, 1-naphthoic acid, and 2-naphthoic acid) undergo a 1:1:1 addition reaction under mild conditions in a one-pot reaction to afford novel series of fully substituted 1,3,4-oxadiazole derivatives in good yields.     

N.m.r. studies on aromatic compounds. I—13C n.m.r. spectra of some mono- and disulpho-substituted hydroxycarboxylic acids

Carbon-13 n.m.r. spectra of 3-hydroxy-4-sulpho-2-naphthoic, 3-hydroxy-5-sulpho-2-naphthoic, 3-hydroxy-7-sulpho-2-naphthoic, 5-sulphosalicylic, 3-hydroxy-5,7-disulpho-2-naphthoic, 1-hydroxy-4,7-disulpho-2-naphthoic, and 3,5-disulphosalicylic acids were recorded with and without proton noise-decoupling. Analyses of the spectra were carried out for all compounds except 3-hydroxy-5-sulpho-2-naphthoic acid which dimerized. The fine splitting caused by long-range coupling was used in identifying the lines of the ¹³C n.m.r. spectra.     

Structures and vibrational frequencies of 2-naphthoic acid and 6-bromo-2-naphthoic acid based on density functional theory calculations

The solid phase mid FTIR and FT Raman spectra of 2-naphthoic acid (NA) and 6-bromo-2-naphthoic acid (BNA) have been recorded in the regions 4000-400 cm(-1) and 3500-100 cm(-1), respectively. The fundamental vibrational frequencies and intensities of the vibrational bands were evaluated using density functional theory (DFT) using standard B3LYP method and 6-311+G** basis set combinations. The vibrational spectra were interpreted, with the aid of normal coordinate analysis based on a scaled quantum mechanical force field. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes.     

Potentiometrische Studien an Mischligand-Komplexen

1∶1∶1, mixed ligand complex formation of La(III) with ethylenediamine-N,N,N′,N′-tetra-acetic acid and certain hydroxy acids such as malic, tartaric, 1-hydroxy-2-naphthoic and 2-hydroxy-3-naphthoic acids has been shown potentiometrically.     

钝化萘衍生物的磺化反应研究

研究了带吸电子取代基的一系列钝化萘衍生物与SO~3进行的磺化反应, 用^1H NMR分析反应混合物的组成.1-萘磺酸以71:20:9的比例产生1,5-, 1,6-和1,7-萘二磺酸, 进一步磺化得到1,3,5-, 1,3,6-萘三磺酸和1,3,5,7-萘四磺酸. 1-萘甲醛的单硫化得到比例为55:9:6:30的5-, 6-,7-和8-磺酸取代物. 1-苯甲酮萘则以83:11:6的比例得到5-,6-,和7-磺酸取代物. 1-硝基萘仅得到5位磺化产物. 1-萘甲酸和1-萘甲酸甲酯得到5位和8位取代产物. 所有的2位取代萘衍生物均先得到5和8位取代产物. 提出了生成SO~3络合物及迫位磺化的历程.     

Substitution and addition reactions of organic substrates with hypofluorous acid

The chemical reactions of hypofluorous acid with aromatic and olefinic substrates show considerable variety. Hypofluorous acid reacts with naphthalene to give 1-naphthol, 2-naphthol and 1,4-naphtho-quinone; with benzo[b]thiophen to give the 1,1-dioxide; with trans-stilbene to give threo-2-fluoro-1-hydroxy-1, 2-diphenylethane, benzophenone and diphenylacetaldehyde; and with cholesteryl acetate to give the two epoxides (α:β = 6.3:1) and two fluorohydrins (6β-fluoro-5β-o1 and 5α-fluoro-6β-o1).     

Spectrophotometric determination of iron with 1-hydroxy-4-sulpho-2-naphthoic acid

1-Hydroxy-4-sulpho-2-naphthoic acid (H(3)L) is proposed as a spectrophotometric reagent for determination of iron. It gives a red-brown chelate, FeL(6-)(3), with lambda(max) 500-520 nm at pH 8 ( = 3.3 x 10(3) l. mole(-1). cm(-1)). In this wavelength region the reagent has no absorption. Most common cations and oxo-anions do not interfere. In the determination of iron in polymetallic iron ores and aluminium alloys the relative error and relative standard deviation of the method were found to be better than 1 and 0.5%, respectively. 1-Hydroxy-4-sulpho-2-naphthoic acid seems to be a more sensitive and accurate reagent for iron than 5-sulphosalicylic acid, and the number of interfering ions is smaller than in the 1,10-phenanthroline or thiocyanate methods.     

Synthesis of 7-benzoxazol-2-yl and 7-benzothiazol-2-yl-6-fluoroquinolones

The fluoroquinolones, 7-benzoxazol-2-yl-1-ethyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid and 7-benzothiazol-2-yl-1-ethyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid, were synthesized. The compounds were obtained by use of the Gould-Jacobs route to the quinoline ring system. The required anilines, 3-benzoxazol-2-yl-4-fluorophenylamine and 3-benzothiazol-2-yl-4-fluorophenylamine were obtained by the cyclodehydration reaction of 5-amino-2-fluorobenzoic acid with 2-aminophenol or 2-aminothiophenol respectively using polyphosphoric acid.     

An efficient synthesis of 6-fluoronalidixic acid and its conversion to enoxacin

1-Ethyl-6-fluoro-1,4-dihydro-7-methyl-4-oxo-1,8-naphthyridine-3-carboxylic acid ( 8 ) has been prepared in large quantities by a highly efficient process. It has in turn been degraded to give 7-chloro-1-ethyl-6-fluoro-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid ( 11 ). This intermediate has been reacted with piperazine to give the known antibacterial agent, enoxacin ( 12 ).     

Synthesis and antibacterial activity of 1-(substituted-benzyl)-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acids and their 6,8-difluoro analogs

Alkylation of 6,7-difluoro-4-hydroxyquinoline-3-carboxylic acid ethyl ester with substituted-benzyl chlorides gave 1-(substituted-benzyl)-6,7-difluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid ethyl esters. Their treatment with piperazine or N-methylpiperazine in pyridine yielded 1-(substituted-benzyl)-6-fluoro-1,4-dihydro-4-oxo-7-(l-piperazinyl)quinoline-3-carboxylic acid ethyl esters which were hydrolyzed with aqueous sodium hydroxide and then acidified with hydrochloric acid afforded the desired 1-(substituted-benzyl)-6-fluoro-1,4-dihydro-4-oxo-7-(1-iperazinyl)quinoline-3-carboxylic acids. The 6,8-difluoro analogs were prepared similarly using 6,7,8-trifluoro-4-hydroxyquinoline-3-carboxylic acid ethyl ester as a starting material. Some of these quinolones demonstrated fairly good antibacterial activities. Among them, 6-fluoro-1-(4-fluorophenylmethyl)-1,4-dihydro-7-(1-iperazinyl)-4-oxoquinoline-3-carboxylic acid ( 7d ) and 6,8-difluoro-1-(3-fluorophenylmethyl)-1,4-dihydro-7-(1-piperazinyl)-4-oxoquinoline-3-carboxylic acid ( 8c ) are two of the best.     

Synthesis,pharmacokinetics, and biological activity of a series of new pyridonecarboxylic acid antibacterial agents bearing a 5-fluoro-2-pyridyl group or a 3-fluoro-4-pyridyl group at N-1

The 1-(5-fluoro-2-pyridyl) or 1-(3-fluoro-4-pyridyl) group was introduced in the syntheses of new pyridonecarboxylic acid antibacterial agents. 1-(5-Fluoro-2-pyridyl)-6-fluoro-1,4-dihydro-7-(4-methyl-1-piperazinyl)-4-oxoquinolone-3-carboxylic acid 7b (DW-116) showed a moderate in vitro antibacterial activity but it was found to have very excellent pharmacokinetic profiles so that 7b (DW-116) showed dramatic increased in vivo efficacy.     

Zur Synthese sulfonierter Derivate von 2-Fluoranilin

Syntheses of Sulfonated Derivatives of 2-Fluoroaniline Synthesis of 4-amino-3-fluorobenzenesulfonic acid ( 3 ) was achieved in two ways: reaction of 2-fluoroaniline ( 1 ) with amidosulfonic acid and by first conventionally converting 4-nitro-3-fluoroaniline ( 8 ) to 4-nitro-3-fluorobenzenesulfonyl chloride ( 9 ) followed subsequently by hydrolysis to 3-fluoro-4-nitrobenzenesulfonic acid ( 10 ) and reduction. Hydrogenolysis of 3 gave sulfanilic acid ( 7 ). Both, sulfonation of fluorobenzene ( 6 ) to 4-fluorobenzenesulfonic acid ( 11 ) followed by nitration and sulfonation of 1-fluoro-2-nitrobenzene ( 12 ) led to 4-fluoro-3-nitrobenzenesulfonic acid ( 13 ). Reduction of 13 gave the isomeric 3-amino-4-fluorobenzenesulfonic acid ( 4 ), which was also obtained both by sulfonation of 1 and by sulfonation of o-fluoroacetanilide ( 14 ) followed by hydrolysis. Selective hydrogenolyses of 2-amino-5-bromo-3-fluorobenzenesulfonic acid ( 15 ), prepared by reaction of 4-bromo-2-fluoroaniline ( 16 ) with amidosulfonic acid, and of 4-amino-2-bromo-5-fluorobenzenesulfonic acid ( 20 ), obtained by sulfonation of 5-bromo-2-fluoroaniline ( 19 ) yielded the isomers 2-amino-3-fluorobenzenesulfonic acid ( 5 ) and 3 , respectively. The fourth isomer, 3-amino-2-fluorobenzenesulfonic acid ( 2 ), was synthesized by sulfur dioxide treatment of the diazonium chloride derived from 2-fluoro-3-nitroaniline ( 21 ) to 2-fluoro-3-nitrobenzenesulfonyl chloride ( 22 ), followed by hydrolysis to 2-fluoro-3-nitrobenzenesulfonic acid ( 23 ) and final Béchamp-reduction.     

Synthesis of some novel 7-substituted quinolonecarboxylic acids via nitroso and nitrone cycloadditions

1-Ethyl-6-fluoro-7-hydroxylamino-1,4-dihydro-4-oxoquinoline-3-carboxylic acid 7 can be either oxidized to the corresponding nitroso intermediate 8 or converted to the methylene nitrone 9. Both intermediates form cycloaddition products with selected dienes and olefins respectively. Also, the preparation of 1-ethyl-6-fluoro-7-(hexahydro-2-methyl-5H-pyrrolo[3,4-d]isoxazol-5-yl)-3-quinolinecarboxylic acid 5 via a nitrone cycloaddition is presented.     

Preparation and X-ray crystal study of benziodoxaborole derivatives: new hypervalent iodine heterocycles

A series of heterocyclic compounds containing trivalent iodine, oxygen, and boron in a five-membered ring were prepared and structurally investigated by X-ray crystallography. 1-Chloro-4-fluoro-1H-1λ(3)-benzo[d][1,2,3]iodoxoborol-3-ol was synthesized by chlorination of 2-fluoro-6-iodophenylboronic acid followed by treatment of the intermediate iododichloride with water. 1-Acetoxy-4-fluoro-1H-1λ(3)-benzo[d][1,2,3]iodoxoborol-3-ol, 1-acetoxy-1H-1λ(3)-benzo[d][1,2,3]iodoxoborol-3-ol, and similar 1-substituted trifluoroacetate derivatives of benziodoxaborole were prepared the hypochlorite oxidation of 2-fluoro-6-iodophenylboronic acid or 2-iodophenylboronic acid in acetic or trifluoroacetic acid, respectively. 1-Acetoxy substituted benziodoxaborole can be further converted to the respective trifluoroacetate by treatment with trifluoroacetic acid or to the 1-hydroxy derivative by basic hydrolysis with aqueous NaHCO(3). X-ray structural studies of 1-chloro- and 1-trifluoroacetoxy substituted benziodoxaboroles 13, 17, and 18 have shown the presence of a planar five-membered heterocyclic ring with unusually short endocyclic I-O bond distance of 2.04-2.09 ?. Slow crystallization of 4-fluoro-1-trifluoroacetoxy-1H-1λ(3)-benzo[d][1,2,3]iodoxoborol-3-ol from methanol resulted in the formation of a tetrameric macrocyclic structure 21 resulting from self-assembly of the initially formed 4-fluoro-1,3-dimethoxy-1H-1λ(3)-benzo[d][1,2,3]iodoxoborol. Structural parameters of the five-membered iodoxoborol ring, such as the planar geometry and the short B-O and O-I bonds lengths in 13, 17, and 18 compared to those in 21 and known benziodoxoles are indicative of partially aromatic character of this ring. Density functional theory (DFT) predicted NIST (0) and NIST (1) indexes for 1-chloro- and 1-trifluoroacetoxy substituted benziodoxaboroles, however, are indicative of significantly lower aromaticity compared to the classic aromatic systems.     

Aromatic retinoids: A short synthesis of 7-hydroxy-6-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-napthyl)-2-naphthoic acid, (7-hydroxy-TTNN).

7-hydroxy-TTNN, a possible metabolite of the aromatic retinoid: 6-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthyl)-2-naphthoic acid (TTNN) (2), was synthesized through a short route, the key step of which was a one pot oxidation/cyclisation/aromatisation of a 1,5 diol to afford the phenolic ring C (see scheme 1).     

Synthesis of 6-hydroxy-2-naphthoic acid from 2,6-diisopropylnaphthalene using NHPI as a key catalyst

A new strategy to 6-hydroxy-2-naphthoic acid (HNPA) and 4-hydroxybenzoic acid from 2,6-diisopropylnaphthalene and p-cymene, respectively, was developed using the NHPI-catalyzed aerobic oxidation as a principal reaction. 2,6-Diisopropylnaphthalene was oxidized by the oxidation with O₂ (1 atm) by NHPI (10 mol %) combined with Co(OAc)₂ (0.5 mol %) to give 6-acetyl-2-isopropylnaphthalene, which then was converted to 6-isopropyl-2-naphthoic acid under O₂ (1 atm) in the presence of Co(OAc)₂ (0.5 mol %) and Mn(OAc)₂ (0.5 mol %). Esterification of the resulting acid followed by the aerobic oxidation produced methyl 6-hydroxy-2-naphthoate whose hydrolysis led to the desired HNPA. An alternative route involves the oxidation of 6-acetyl-2-isopropylnaphthalene to 6-acetyl-2-naphthol on which subsequent oxidation and deacetylation gave HNPA. This method was successfully extended to the synthesis of 4-hydroxybenzoic acid from p-cymene.