bluuebunny/crossref_metadata_2025_split huggingface dataset:
Neighboring Group Participation in Solvolysis. X. Dissection of Ar1-5 and Ar2-6 Pathways in Trifluoroacetolysis of 4-Arylbutyl 6-Methyl-2-naphthalenesulfonates
Authors: Ando Takashi , Yamawaki Junko , Saito Yoshimasa , Takai Yoshio , Yamataka Hiroshi 
Published: July 2006

Abstract
Trifluoroacetolysis rates and products were determined for eleven 4-(m- and p-substituted phenyl) butyl 6-methyl-2-naphthalenesulfonates. Most substrates solvolyze predominantly or even exclusively with aryl assisted (kΔ) pathway. Dissection of kΔ into Ar1-5 and Ar2-6 components was performed by means of quantitative 13C NMR study of suitably labeled p-methyl and p-fluoro derivatives; the results were 32.4% Ar1-5 and 67.6% Ar2-6 for the former and 43.3% Ar1-5 and 56.7% Ar2-6 for the latter. For other substrates the dissection was carried out by postulating two independent linear free energy relationships (LFER) for the two pathways determined by the above four partial rates. Ar2-6 is much prefered over Ar1-5 through the series; for the unsubstituted derivative 90.6% Ar2-6 vs. 9.4% Ar1-5 was determined. A completely different approach by means of non-linear regression analysis of kΔ as a sum of two independent LFER gave fairly different and rather unsettled results, limitations of such an approach being suggested. The characteristics of remote aryl participation are discussed based on the above data.
Oxidation Studies with Peroxomonophosphoric Acid. III. A Kinetic and Mechanistic Study of Oxidation of Dialkyl Sulfides
Authors: Panigrahi Ganesh Prasad , Panda Radhasyam 
Published: July 2006

Abstract
The kinetics of oxidation of dialkyl sulfides by peroxomonophosphate in aqueous medium at 308 K and μ=0.4 mol dm−3 follow the rate expressions (i) −d[peroxomonophosphate]/dt={k1[H2PO5−]+k2[HPO52−]}[sulfide] in the pH region 6.8–8.7 where k1 and k2 values are 336.5 and 0.95, 69.7 and 0.254, and 27.5 and 0.126 dm3 mol−1 s−1 for dimethyl, diethyl and dipropyl sulfides, respectively, (ii) −d[peroxomonophosphate]/dt=k2[HPO52−]·[sulfide] in the pH region 8.5–12.5, where the average k2 values are 0.86, 0.247, and 0.128 dm3 mol−1 s−1 for dimethyl, diethyl, and dipropyl sulfides, respectively, and (iii) −d[peroxomonophosphate]/dt={k2[HPO52−]+k3·[PO53−]}[sulfide] in the pH region 12.5–13.7, the k2 and k3 values being 0.947 and 0.107, and 0.233 and 0.018 dm3 mol−1 s−1 for dimethyl, and diethyl sulfides, respectively. The mechanism of the reaction is in line with a nucleophilic attack of the sulfide-sulfur on the peroxo oxygen, giving rise to SN 2-type transition states which undergo oxygen-oxygen bond fission to give the corresponding sulfoxide and phosphate.
Concentration Dependence of Flow Properties of Molten Salt Systems
Authors: Islam Nurul , Ali Anwar 
Published: July 2006

Abstract
The concentration dependence of fluidities and conductances of molten calcium nitrate tetrahydrate–MNCS (M=Na+ or NH4+) systems was quantitatively explained by the isoenergetic and isoentropic equations essentially based on the Vogel-Tammann-Fulcher (VTF) and the Configurational Entropy Model (CEM) equations. The pre-exponential terms of the VTF and the Doolittle’s equations were found to depend linearly on the values of the corresponding parameters, i.e., T0 the zero mobility temperature and those of V0, the molar intrinsic volume at T0, respectively. The linear interdependence of the two thermodynamic parameters, T0 and V0 on each other has been demonstrated. In addition to the linear dependence of the corrected energy of activation, Ecor on V0, a physically meaningful linear dependence of Ecor on T0 has also been demonstrated.
Determination of Uranium and Thorium with Arsenazo III after Sequential Extraction from Acid-deficient Aluminium Nitrate Medium
Authors: Ramakrishna T V , Shreedhara Murthy R S 
Published: July 2006

Abstract
Uranium has been quantitatively extracted into IBMK from ≈2.2 mol dm−3 aluminium nitrate solution at pH 0.8–0.9. Coextracted thorium (≈10%) is returned to the aqueous phase by addition of benzene. Subsequently, thorium is extracted into IBMK in the presence of hexadecyltrimethylammonium bromide (CTAB). This separation method has been applied to the analysis of uranium and thorium content of monazite sand.
An ESR Study of N,N-Bis(arylthio)aminyls. 33S Hyperfine Splittings
Authors: Miura Yozo , Kinoshita Masayoshi 
Published: July 2006

Abstract
In the ESR spectra of N,N-bis(phenylthio)-, N,N-bis(phenyl-d5-thio)-, and N,N-bis(3,5-dichlorophenylthio)aminyls, 33S hyperfine splittings were detected. The spin densities in the aminyls were calculated by using the HMO calculations with and without McLachlan’s correction, and the results were compared with the values derived from the 1H, 14N, and 33S hyperfine splittings by use of the relationship a=Qρ.
Liquid Phase Peptide Synthesis by Fragment Condensation on Soluble Polymer Support. IV. Relative Reactivities of N-t-Butoxycarbonyl-(Boc)amino Acids and Boc-Oligopeptide Acids in Their Esterification with Soluble Chloromethylated Polystyrene
Authors: Narita Mitsuaki , Kusano Kazuya , Hirata Masanori , Okawara Makoto 
Published: July 2006

Abstract
Relative reactivities of N-t-butoxycarbonyl(Boc)amino acids (Gly, Val, Ile, Leu, Tyr, and Phe) and Boc-oligopeptide acids having various numbers of amino acid residues (n=2, 4, 5, 8, and 10) were determined by competitive esterification in reaction with chloromethylated polystyrene. Increase of peptide-chain lengths reduced reactivity of C-terminal carboxylates.
Synthesis of 1-Benzothiopyrylium Perchlorates and Related Compounds
Authors: Nakazumi Hiroyuki , Kitao Teijiro 
Published: July 2006

Abstract
The blue colored 1-benzothiopyrylium perchlorates were synthesized by the reduction of thiocoumarins with lithium aluminium hydride followed by the treatment with acid. A number of new thiocarbonyl derivatives of thiocoumarins and thiochromones were also synthesized, the spectral characterization of which has been described.
Reaction of Phenacyltriphenylarsonium Bromides with N-Methylaniline and N,N-Dimethylaniline
Authors: Bansal Raj Kumar , Bhagchandani Gope 
Published: July 2006

Abstract
Reaction of phenacyltriphenylarsonium bromide with N-methylaniline furnished 2-phenylindole predominantly together with 1-methyl-2-phenylindole. The corresponding reaction of the arsonium salt with N,N-dimethylaniline did not give any indole, instead a simple nucleophilic substituted product, α-4′-(dimethylamino)deoxybenzoin was obtained. But, the latter reaction on being carried out in presence of hydrobromic acid afforded 1-methyl-2-phenylindole by the demethylation of N,N-dimethylaniline.
Resonance Raman Spectra of Intermolecular Vibrations of Würster’s Cation Dimers
Authors: Yokoyama Kenji , Tajima Yoshitaka , Tahara Masao , Maeda Shiro 
Published: July 2006

Abstract
The resonance Raman spectra of some Würster’s cation dimers were measured in alcohol solution at 201 K and in glassy matrix at 77 K. The spectra of the dimer of p-phenylenediamine cation showed the resonance enhancement of the Raman line assigned to the intermolecular stretching vibration and supported the D2h symmetry for the dimer. However, for the dimer of 2,3,5,6-tetramethyl-p-phenylenediamine cation and N,N-dimethyl-p-phenylenediamine cation, it was supposed that D2h symmetry was broken down in alcohol solution and in glassy matrix, because the dimers had two Raman lines in the region of the intermolecular vibration.
Precipitation and Microflotation of Egg Albumin and Hemoglobin in the Presence of Dioctadecyldimethylammonmin Chloride
Authors: Nakayama Haruo , Itoh Kazuo , Shinoda K\={o}z\={o} , Matijevic Egon 
Published: July 2006

Abstract
Precipitation and microflotation of egg albumin and of hemoglobin was studied as a function of pH in the presence of dioctadecyldimethylammonium chloride (DOAC). The “DOAC concentration-pH” stability domains for both protein solutions (0.05 wt%) exhibited similar boundaries. Efficient separation by precipitation (more than 80% after 24 h) occurs at pH&gt;5.0 for albumin and at pH&gt;6.3 for hemoglobin. The same amount of removal by microflotation required 5 min under otherwise similar conditions. The DOAC concentration for optimal separation of proteins (from 0.05 wt% solutions) is 0.02 wt% at pH 6–8 for albumin and 0.015 wt% at pH 6.5–8 for hemoglobin. It is noteworthy that both proteins can be precipitated and also foam separated even in strongly alkaline media, such as at pH 12, where the usual flocculents (e.g., aluminum salts) cannot be employed. This work points out the usefulness of infinitely aggregating surfactants as microflotation agents.
Studies of Thermochemical Hydrogen Production. VII. Vapor-Liquid Equilibrium for Sulfur Dioxide–Bromine–Hydrobromic Acid–Sulfuric Acid–Water System
Authors: Ishikawa Hiroshi , Ishii Eiichi , Uehara Itsuki , Nakane Masanori 
Published: July 2006

Abstract
In order to eliminate SO2 from HBr gas produced by the reaction between SO2, Br2, and H2O, vapor-liquid equilibrium measurements of the Br2–H2SO4–H2O system saturated with HBr have been made over a wide range of the constituent concentrations. Experiments were carried out in a semi-flow system at 25 °C under atmospheric pressure. The relative concentration of HBr saturated in the liquid phase decreased from 0.31 to 0.05 [mol]/[mol] with an increase in the relative H2SO4 concentration from 0.0 to 0.40 [mol]/[mol]. The solubility of Br2, as defined by Henry’s law constant, varied from 1.1 to ca. 150 atm/mol/mol with the above-mentioned decrease in the HBr concentration. The relation between the partial pressure of SO2 in the gas phase and the composition of the liquid phase was found to be expressed by the following empirical formula: PSO2=K·CHBr·CH2SO4⁄CBr2, where the value of K is 8×10−4 when C is expressed as a relative molar concentration for each species in the liquid phase. The unconverted SO2 can be effectively removed by bringing the effluent gases from the reactor into contact with a HBr-saturated aqueous solution containing an excess of Br2.
Synthesis and Circular Dichroism Spectra of [Co(a)(gly)(1,4,7-triazacyclononane)]-type Complexes
Authors: Shimba Satoru , Fujinami Shuhei , Shibata Muraji 
Published: July 2006

Abstract
Complexes of the [Co(a)(gly)(tacn)]-type, where tacn represents 1,4,7-triazacyclononane and a is CN−, NO2−, NH3, NCS−, H2O, OH−, N3−, or Cl−, have been prepared and resolved. The CD spectra of these complexes have been measured. On the basis of the X-ray analysis of (−)589[Co(gly)(NH3)(tacn)]I2·H2O, the absolute configurations of the other complexes have been assigned by referring to the CD spectra. These complexes have exhibited a common CD pattern in the T1g-band region, and from this fact a criterion for the assignments of the absolute configurations for the complexes of the fac(D)-[Co(a)(BC)(DDD)]-type has been established.
Mixed-ligand Complexes of Cobalt(III) with 1-(2-Pyridylazo)-2-naphthol (PAN) and Diethylenetriamine (dien) or Triethylenetetramine (trien)
Authors: Mochizuki Katsura , Fujimoto Masatoshi 
Published: July 2006

Abstract
New mixed-ligand complexes [CoIII(pan)(dien)](ClO4)2·EtOH and [CoIII(pan)(trien)](ClO4)·NaClO4 were synthesized. The 1H NMR and the visible absorption spectra of these complexes were compared with those of the free ligand PAN and [CoIII(pan)2]Cl. A remarkable down-field shift observed in the 1H NMR signal for the proton H10 of the cobalt(III) complexes reflects the structural changes in the PAN molecule upon chelatering formation. The reaction between [CoIIICl2(trien)]Cl and PAN gave two kinds of products, which confirmed a strong tendency for the ligand PAN to behave as a planar terdentate ligand.
Spin-state Equilibria of the Nickel(II) Complexes of 2,12-Dimethyl 3,7,11,17-tetraazabicyclo[11.3.1]heptadeca-1(17),2,11,13,15-pentaene Analogs in Water
Authors: Mochizuki Katsura , Fujimoto Masatoshi , Ito Haruko , Ito Tasuku 
Published: July 2006

Abstract
Spin-state equilibria between a singlet low-spin and a triplet high-spin species of the title complexes in water were investigated by means of electronic spectra. The equilibrium constants and the thermodynamic parameters, ΔH and ΔS, were evaluated from detailed analysis of the temperature-dependence of the electronic spectra. The electronic spectra of the singlet and the triplet species involved were also derived, from the same analysis. The formation of the triplet species was found to be exothermic, which reflects the predominant contribution of the exothermic change to the formation of nickel(II)–water bond over the contribution of the endothermic change in the bond length caused by the change in spin state. The absolute values of ΔS almost correspond to those expected for the effective liberation of two molecules of water in aqueous solution.
Synthesis of erythro- and threo-γ-Hydroxy-l-ornithines
Authors: Mizusaki Koichi , Yamamoto Hidefumi , Makisumi Satoru 
Published: July 2006

Abstract
γ-Hydroxy-Dl-ornithine was obtained from an alkaline hydrolysate of 2,5-diamino-4-pentanolide synthesized according to the method of Talbot et al. The amino acid preparation was found to be a racemic mixture composed of 34% erythro and 66% threo isomers by a new chromatographic assay. This assay is based on the conversion of the basic amino acid to a neutral amino acid by acetylation of the δ-amino group and the analysis of the resulting Nδ-acetyl derivative with an automatic amino acid analyzer by the ordinary method. Two diastereoisomers of γ-hydroxy-Dl-ornithine were separated by column chromatography on Dowex 50 and isolated as their crystalline hydrochlorides. Guanidination of the separated racemic diastereoisomers gave the corresponding diastereoisomeric γ-hydroxyarginines, hydrolysis of which with arginase yielded erythro- and threo-γ-hydroxy-Dl-ornithines.
Photo- and Thermally-induced Radical Rearrangement of 4,4-Dimethyl-5-cholesten-3β-ol Hypoiodite in the Presence of Mercury(II) Oxide and Iodine
Authors: Suginome Hiroshi , Maeda Norio 
Published: July 2006

Abstract
Irraidation of a benzene solution of hypoiodite of 4,4-dimethyl-5-cholesten-3β-ol (1) in the presence of mercury(II) oxide and iodine gave a mixture of products, from which 3α,5-epoxy-6β-iodo-A-homo-4-oxa-5α-cholestane (2%), 4,4-dimethyl-3-oxa-5-cholestene (3) (10%), and 4a,4a-dimethyl-3α,5-epoxy-A-homo-4-oxa-5α-cholest-6-ene (4) (4%) were isolated. The thermally-induced reaction on 1 conducted at 55–60 °C gave 3 and 4 in lower yields. The reaction with the use of lead tetraacetate-iodine reagent also gave a complex mixture, from which only 4 was obtained in 22% yield. The formation of 4,4-dimethyl-3-oxa-5-cholestene skeleton is parallel with the case of the photo- and thermally-induced reactions of hypoiodite of 3α,4,4-trimethyl-5-cholesten-3β-ol and appears to be particular with 5-cholesten-3β-ol bearing dimethyl groups at the C-4 under similar conditions. The formation is explained in terms of radical-induced decarbonylation of initially formed 4,4-dimethyl-2-formyl-3-oxa-5-cholestene.
Liposomal Membranes. III. Permeation of Pyrene-labeled Lecithin into Matrix of Liposomal Bilayers
Authors: Sunamoto Junzo , Nomura Tadashi , Okamoto Hiroshi 
Published: July 2006

Abstract
The permeation of a novel pyrene-labeled phosphatidylcholine, DPDL (1,2-bis[10-(1-pyrenyl)decanoyl]-sn-glycero-3-phosphatidylcholine), into the dipalmitoyl and egg phosphatidylcholine liposomes was studied. DPDL can adopt a sandwich conformation at the ground state, which comes in the fluorescence excimer emission. The fluorescent probe undergoes the initial rapid adsorption onto the liposome surfaces along with the instantaneous fluorescence enhancement followed by the relatively slow permeation into and diffusion in the liposomal bilayers. Through monitoring the relative quantum efficiency, Ie⁄Im (see text), during the permeation, suggestive information about the bilayer structure is obtained at least around the probe. The initial binding to and the subsequent diffusion in the membrane occur mostly as the monomeric form of the probe. At lower temperature without cholesterol the bilayer structure seems to be a lipid-separated conformation (Fig. 1 (c)) and above the chain-melting transition the bilayer seems to exist as a lipid-intimate conformation (Fig. 1 (b)). These results completely coincide with those obtained in our previous study on the codispersion of the probe with phospholipids (J. Sunamoto, et al., J. Am. Chem. Soc., 102, 1146 (1980)).
Enrichment and Spectrophotometric Determination of a Trace Amount of Chromium(VI) as the Diphenylcarbazide Complex on a Mixed Resin Prepared from Finely Divided Anion and Cation Exchangers
Authors: Ohzeki Kunio , Sakuma Toshiaki , Kambara Tomihito 
Published: July 2006

Abstract
A rapid and sensitive method has been developed for the determination of a trace amount of chromium(VI). It is based on the pre-concentration of chromium(VI) as the diphenylcarbazide (DPC) complex on a mixed resin prepared from finely divided anion and cation exchangers and the subsequent measurement of absorbance of the resin phase after collection on a filter paper as a uniform thin layer. The sensitivity of the method is approximately 100 times higher than the ordinary solution method using 1-cm cell. The extraction of chromium(VI) with tributyl phosphate followed by back extraction into water is effective for reducing the influence of interfering ions.
Dehydrooligopeptides. I. The Facile Coupling of α-Amino Acids with α-Dehydroamino Acids to Dehydrodipeptides
Authors: Yonezawa Yasuchika , Shin Chung-gi , Ono Yuji , Yoshimura Juji 
Published: July 2006

Abstract
N-Cbz- or N-Tos-α-dehydroamino acid (DHA) and its ester were prepared by the condensation of 2-oxo carboxylic acid or ester with benzyl carbamate or p-toluenesulfonamide. Subsequently, the N-protected DHA and its N-free ester thus obtained were coupled with several l-α-amino acid esters and N-protected (Boc or Cbz)-l-α-amino acid respectively by the usual peptide synthetic methods to give a number of different types of dehydrodipeptide. The configurations of all the new DHA and dehydrodipeptides obtained were shown to have (Z)-geometry.
New Methods for Stereoselective Synthesis of α-Alkylidene-γ-butyrolactones Using Monoanion of O-Ethyl S-(Tetrahydro-2-oxo-3-furanyl) Thiocarbonate and Dianion of α-Mercapto-γ-butyrolactone
Authors: Tanaka Kazuhiko , Uneme Hideki , Yamagishi Nobuyuki , Tanikaga Rikuhei , Kaji Aritsune 
Published: July 2006

Abstract
The lithium enolates of O-ethyl S-(tetrahydro-2-oxo-3-furanyl) dithiocarbonate and thiocarbonate were found to be efficient reagents for the stereoselective synthesis of α-alkylidene-γ-butyrolactones from carbonyl compounds. The dianion of α-mercapto-γ-butyrolactone was successfully generated by treatment of α-mercapto-γ-butyrolactone with 2.2 equivalents of lithium diisopropylamide in the presence of N,N,N′,N′-tetramethylethylenediamine at −78°C in THF. The dianion thus formed has been utilized for the efficient and stereoselective synthesis of α-alkylidene-γ-butyrolactones from carbonyl compounds.
Synthetic Studies via Arene-Metal Compounds. An Application to the Regioselective Synthesis of a Natural Phthalide
Authors: Uemura Motokazu , Nishikawa Naomi , Tokuyama Satoru , Hayashi Yuji 
Published: July 2006

Abstract
A naturally occuring methoxyphthalide derivative, a constituent of Othonna Cylindrica Dc, was synthesized by employing stereoselective carbonyl reduction of (η-arene)tricarbonylchromium complex and regioselective lithiation of 7-methoxy-2-(1-hydroxyethyl)-1-tetralol.
A Convenient One-step Preparation of Oxacyclanes by Dehydration of Diols over Alumina
Authors: Inoue Yoshihisa , Deguchi Shokichiro , Hakushi Tadao 
Published: July 2006

Abstract
Dehydration of 1,4-, 1,5-, or 1,6-alkanediols over alumina at 220–250 °C in a distillation apparatus gave the corresponding 5- to 7-membered oxacyclanes in good yield of 51–71%. Diethylene glycol also gave 1,4-dioxane in 49% yield, whereas attempted one-step synthesis of crown ethers from polyethylene glycols in a similar manner resulted in the predominant formation of 1,4-dioxane without any trace of crown ether.
Structural Studies on Fortimicins. III. The Crystal and Molecular Structure of Fortamine Dihydrochloride
Authors: Hirayama Noriaki , Shirahata Kunikatsu , Ohashi Yuji , Sasada Yoshio 
Published: July 2006

Abstract
Fortamine dihydrochloride, C8H18N2O4·2HCl, is obtained by the hydrolysis of fortimicin B with hydrochloric acid. The space group is C2 with a=16.109(2), b=10.047(1), c=8.603(1) Å, β=108.69(1)°, and Z=4. The structure was solved by the heavy atom method, and least-squares refinement using 1564 reflexions led to the final R value of 0.030. The ring conformation of fortamine dihydrochloride is an inversed chair form of fortamine. The chair form is significantly compressed to relax the non-bonded interactions between axial substituents.
The Structure of (Hydrogen Ethylenediaminetetraacetato)antimony(III) Dihydrate Sb(C10H13N2O8)·2H2O
Authors: Shimoi Mamoru , Orita Yoshinari , Uehiro Takashi , Kita Itsuro , Iwamoto Toschitake , Ouchi Akira , Yoshino Yukichi 
Published: July 2006

Abstract
The crystal and molecular structure of the title complex has been determined by X-ray diffraction using 1882 reflections. The crystal was orthorhombic, with the space group Pbn21; a=10.98(2), b=18.496(4), c=7.341(9), Z=4, Dx=1.99, Dm=1.98(2) g cm−3,μ(Mo Kα)=19.3 cm−1, and the final R value was 0.036. A distorted ψ-pentagonal bipyramid is formed around the central antimony(III) atom by two nitrogen and two oxygen atoms, together with a lone electron pair at the equatorial positions and two oxygen atoms at the axial positions. One of the Sb–O distances, 2.78 Å, is longer than the others (2.20(2) Å on the average), and it is determined that the carbonyl oxygen is essentially of the free-acid type and that its carbonyl oxygen is weakly coordinated. The splitting of the νas(COO) band of its infrared and Raman spectra shows the existence of both free and coordinated carboxyl groups. The 1H- and 13C-NMR results show that the antimony(III)–edta complex does not exchange with the free ligand in an aqueous solution at pH 1.5–3.5.
The Crystal and Molecular Structure of Palythine Trihydrate
Authors: Furusaki Akio , Matsumoto Takeshi , Tsujino Isami , Sekikawa Isao 
Published: July 2006

Abstract
The molecular structure of palythine, C10H16N2O5, has been confirmed by means of an X-ray crystal analysis of its trihydrate. The crystals are monoclinic, with two formula units in a unit cell with dimensions of a=10.499, b=12.812, c=5.322 Å, and β=98.53°; the space group is P21. 1377 unique intensity data were collected on a four-circle diffractometer with LiF-monochromated Cu Kα radiation. The structure was solved by the Monte Carlo direct method, using the 20 strongest reflections as a starting set, and was refined by the block-diagonal least-squares method. The final R value was 3.1%. The molecular structure thus obtained corresponds to that proposed by Tsujino et al. and Takano et al. on the basis of the chemical evidence. Palythine exists as a zwitter ion in the crystal. The palythine and water molecules are connected by twelve types of hydrogen bonds, forming a three-dimensional hydrogen-bonded structure.
The Determination of Kojic Acid Using the Stopped-flow Method
Authors: Tanigaki Hiroshi , Obata Hitoshi , Tokuyama Tai 
Published: July 2006

Abstract
A kinetic method of the determination of kojic acid with 2,6-dichlorophenolindophenol(DCIP) is described. The oxidized form of DCIP, reacting with kojic acid, changes to the colorless reduced form of DCIP. By spectrophotometrically measuring the rate of discoloration, the apparent first-order rate constant, kapp, and the second-order rate constant, k, were obtained. The determination of kojic acid in the fermentation medium is possible by using k the constant, even in the presence of various organic substances.