- Enantioselective Autoinduction in the Asymmetric Hydrocyanation of 3-Phenoxybenzaldehyde Catalyzed by Cyclo
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A new example of enantioselective autoinduction, i.e., and asymmetric reaction that is promted by a chiral catalyst into which the chiral product has been incorporated, has been found in the asymmetric hydrocyanation of 3-phenoxybenzaldehyde catalyzed by cyclo.
- Danda, Hidenori,Nishikawa, Hiroyuki,Otaka, Ken
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- Asymmetric hydrocyanation of aldehydes with cyclo-dipeptides: A new mechanistic approach
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A new mechanistic suggestion for the asymmetric hydrocyanation reaction of aldehydes with cyclo[-(S)-phenylalanyl-(S)-histidyl] (CPH) as catalyst is presented. Kinetic measurements indicate a second order reaction in the cyclopeptide catalyst. A heterogeneous hydrogen bonded polymer of CPH is considered to be the reactive state of the catalyst where two adjacent imidazole bases function as the reactive sites. This structural proposition is also supported by MNDO calculations performed on a dimer of CPH.
- Shvo, Youval,Gal, Meir,Becker, Yigal,Elgavi, Asher
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- 'Gelozymes' in organic synthesis: Synthesis of enantiomerically pure (S)-2-hydroxy-(3-phenoxy)phenylacetonitrile with lipase immobilised in a gelatin matrix
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Lipase from Pseudomonas cepacia (Amano PS and PS Lipase, Fluka) immobilised in microemulsion-based organogels formed by gelatin solubilisation and crosslinking with glutaraldehyde ('Gelozyme') has been used for the alcoholysis of the butanoate ester of racemic 2-hydroxy-(3-phenoxy)phenylacetonitrile with 1-butanol in hexane to obtain (S)-2-hydroxy-(3-phenoxy)phenylacetonitrile. The immobilised enzyme can be used over 25 days (25 cycles) without significant loss of enzyme activity (10%). Copyright (C) 2000 Elsevier Science Ltd.
- Fadnavis, Nitin W.,Luke Babu, Ravi,Sheelu, Gurrala,Deshpande, Ashlesha
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- A study on increasing enzymatic stability and activity of Baliospermum montanum hydroxynitrile lyase in biocatalysis
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HNL catalysis is usually carried out in a biphasic solvent and at low pH to suppress the non-enzymatic synthesis of racemic cyanohydrins. However, enzyme stability under these conditions remain a challenge. We have investigated the effect of different biocatalytic parameters, i.e., pH, temperature, buffer concentrations, presence of stabilizers, organic solvents, and chemical additives on the stability of Baliospermum montanum hydroxynitrile lyase (BmHNL). Unexpectedly, glycerol (50 mg/mL) added BmHNL biocatalysis had produced >99% of (S)-mandelonitrile from benzaldehyde, while without glycerol it is 54% ee. Similarly, BmHNL had converted 3-phenoxy benzaldehyde and 3,5-dimethoxy benzaldehyde, to their corresponding cyanohydrins in the presence of glycerol. Among the different stabilizers added to BmHNL at low pH, 400 mg/mL of sucrose had increased enzyme's half-life more than fivefold. BmHNL's stability study showed half-lives of 554, 686, and 690 h at its optimum pH 5.5, temperature 20 °C, buffer concentration, i.e., 100 mM citrate-phosphate pH 5.5. Addition of benzaldehyde as inhibitor, chemical additives, and the presence of organic solvents have decreased both the stability and activity of BmHNL, compared to their absence. Secondary structural study by CD-spectrophotometer showed that BmHNL's structure is least affected in the presence of different organic solvents and temperatures.
- Jangir, Nisha,Preeti,Padhi, Santosh Kumar
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- Immobilized Baliospermum montanum hydroxynitrile lyase catalyzed synthesis of chiral cyanohydrins
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Hydroxynitrile lyase (HNL) catalyzed enantioselective C–C bond formation is an efficient approach to synthesize chiral cyanohydrins which are important building blocks in the synthesis of a number of fine chemicals, agrochemicals and pharmaceuticals. Immobilization of HNL is known to provide robustness, reusability and in some cases also enhances activity and selectivity. We optimized the preparation of immobilization of Baliospermium montanum HNL (BmHNL) by cross linking enzyme aggregate (CLEA) method and characterized it by SEM. Optimization of biocatalytic parameters was performed to obtain highest % conversion and ee of (S)-mandelonitrile from benzaldehyde using CLEA-BmHNL. The optimized reaction parameters were: 20 min of reaction time, 7 U of CLEA-BmHNL, 1.2 mM substrate, and 300 mM citrate buffer pH 4.2, that synthesized (S)-mandelonitrile in ～99% ee and ～60% conversion. Addition of organic solvent in CLEA-BmHNL biocatalysis did not improve in % ee or conversion of product unlike other CLEA-HNLs. CLEA-BmHNL could be successfully reused for eight consecutive cycles without loss of conversion or product formation and five cycles with a little loss in enantioselectivity. Eleven different chiral cyanohydrins were synthesized under optimal biocatalytic conditions in up to 99% ee and 59% conversion, however the % conversion and ee varied for different products. CLEA-BmHNL has improved the enantioselectivity of (S)-mandelonitrile synthesis compared to the use of purified BmHNL. Nine aldehydes not tested earlier with BmHNL were converted into their corresponding (S)-cyanohydrins for the first time using CLEA-BmHNL. Among the eleven (S)-cyanohydrins syntheses reported here, eight of them have not been synthesized by any CLEA-HNL. Overall, this study showed preparation, characterization of a stable, robust and recyclable biocatalyst i.e. CLEA-BmHNL and its biocatalytic application in the synthesis of different (S)-aromatic cyanohydrins.
- Jangir, Nisha,Padhi, Santosh Kumar
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- PYRETHROID COMPOUND, AND HAIR RESTORER AND HAIR RESTORER COMPOSITION COMPRISING THE SAME
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PROBLEM TO BE SOLVED: To provide a pyrethroid compound having hair growth effect. SOLUTION: The present invention provides a pyrethroid compound represented by general formula (1) [in general formula (1), R1 is selected from a hydrogen atom, a halogen atom, an azido group, an alkoxy group having 1 to 4 carbon atoms, and an alkyl group having 1 to 4 carbon atoms, R2 is selected from a methyl group, an ethyl group and an isopropyl group, R3 is selected from -C≡N, -C≡CH, -C≡C-CH3 and -CH=CH2, and R4 is selected from a methyl group, a phenyl group, a 2-methoxy ethyl group, a methoxymethyl group, and a propargyl group]. SELECTED DRAWING: None COPYRIGHT: (C)2017,JPOandINPIT
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Paragraph 0032; 0036
(2017/08/26)
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- Hydroxynitrile Lyase Isozymes from Prunus communis: Identification, Characterization and Synthetic Applications
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Biocatalysts originating from Badamu (Prunus communis) have been applied to catalyze the asymmetric synthesis of (R)-4-methylsulfanylmandelonitrile, a key building block of thiamphenicol and florfenicol. Here, four hydroxynitrile lyase (HNL) isozymes from Badamu were cloned and heterologously expressed in Pichia pastoris. The biochemical properties and catalytic performances of these isozymes were comprehensively explored to evaluate their efficiency and selectivity in asymmetric synthesis. Among then, PcHNL5 was identified with outstanding activity and enantioselectivity in asymmetric hydrocyanation. Under the optimized mild biphasic reaction conditions, seventeen prochiral aromatic aldehydes were converted to valuable chiral cyanohydrins with good yields (up to 94%) and excellent optical purities (up to >99.9% ee), which provide a facile access to numerous chiral amino alcohols, hypoglycemic agents, angiotension converting enzyme (ACE) inhibitors and β-blockers. This work therefore underlines the importance of discovering the most potent biocatalyst among a group of isozymes for converting unnatural substrates into value-added products. (Figure presented.).
- Zheng, Yu-Cong,Xu, Jian-He,Wang, Hui,Lin, Guo-Qiang,Hong, Ran,Yu, Hui-Lei
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p. 1185 - 1193
(2017/04/13)
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- Fast microwave-assisted resolution of (±)-cyanohydrins promoted by lipase from Candida antarctica
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Enzymatic kinetic resolution (EKR) of (±)-cyanohydrins was performed by using immobilized lipase from Candida antarctica (CALB) under conventional ordinary conditions (orbital shaking) and under microwave radiation (MW). The use of microwave radiation contributed very expressively on the reduction of the reaction time from 24 to 2 h. Most importantly, high selectivity (up to 92percent eep) as well as conversion was achieved under MW radiation (50-56percent).
- Ribeiro, Sandra S.,Ferreira, Irlon M.,Lima, Jo?o P. F.,De Sousa, Bruno A.,Carmona, Rafaela C.,Santos, Alcindo A. Dos,Porto, André L. M.
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p. 1344 - 1350
(2015/07/15)
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- Fenpropathrin biodegradation pathway in bacillus sp. DG-02 and its potential for bioremediation of pyrethroid-contaminated soils
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The widely used insecticide fenpropathrin in agriculture has become a public concern because of its heavy environmental contamination and toxic effects on mammals, yet little is known about the kinetic and metabolic behaviors of this pesticide. This study reports the degradation kinetics and metabolic pathway of fenpropathrin in Bacillus sp. DG-02, previously isolated from the pyrethroid-manufacturing wastewater treatment system. Up to 93.3% of 50 mg L-1 fenpropathrin was degraded by Bacillus sp. DG-02 within 72 h, and the degradation rate parameters qmax, Ks, and K i were determined to be 0.05 h-1, 9.0 mg L-1, and 694.8 mg L-1, respectively. Analysis of the degradation products by gas chromatography-mass spectrometry led to identification of seven metabolites of fenpropathrin, which suggest that fenpropathrin could be degraded first by cleavage of its carboxylester linkage and diaryl bond, followed by degradation of the aromatic ring and subsequent metabolism. In addition to degradation of fenpropathrin, this strain was also found to be capable of degrading a wide range of synthetic pyrethroids including deltamethrin, λ-cyhalothrin, β-cypermethrin, β-cyfluthrin, bifenthrin, and permethrin, which are also widely used insecticides with environmental contamination problems with the degradation process following the first-order kinetic model. Bioaugmentation of fenpropathrin-contaminated soils with strain DG-02 significantly enhanced the disappearance rate of fenpropathrin, and its half-life was sharply reduced in the soils. Taken together, these results depict the biodegradation mechanisms of fenpropathrin and also highlight the promising potentials of Bacillus sp. DG-02 in bioremediation of pyrethroid-contaminated soils.
- Chen, Shaohua,Chang, Changqing,Deng, Yinyue,An, Shuwen,Dong, Yi Hu,Zhou, Jianuan,Hu, Meiying,Zhong, Guohua,Zhang, Lian-Hui
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p. 2147 - 2157
(2014/04/03)
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- Characterization of a novel thermophilic pyrethroid-hydrolyzing carboxylesterase from Sulfolobus tokodaii into a new family
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A novel gene ST2026 encoding a putative carboxylesterase from the thermophilic crenarchaeota Sulfolobus tokodaii (named EstSt7) was cloned and functionally overexpressed in Escherichia coli. The recombinant enzyme was purified to homogeneity after heat treatment, Ni-NTA affinity and Superdex-200 gel filtration chromatography. EstSt7 showed maximum activity at 80 C over 30 min and had a half-life of 180 min at 90 C. Its enzymatic activity was stable in the pH range of 8.0-10.0 with an optimum at 9.0. The enzyme exhibited significant esterase activity toward various p-nitrophenyl esters and the most preferable substrate was p-nitrophenyl butyrate (kcat/Km of 246.3 s-1 mM-1). In addition, EstSt7 showed high activity and stability against organic solvents (20% and 50% v/v) and detergents (1% and 5% v/v). Furthermore, EstSt7 could efficiently hydrolyze a wide range of synthetic pyrethroids including fenpropathrin, permethrin, cypermethrin, cyhalothrin, deltamethrin and bifenthrin, which makes it a potential candidate for the detoxification of pyrethroids for the purpose of biodegradation. Sequence alignment, phylogenetic analysis and comparison of the conserved motif reveal that this novel carboxylesterase EstSt7 should be grouped into a new bacterial lipase and esterase family.
- Wei, Tao,Feng, Shengxue,Shen, Yulong,He, Peixin,Ma, Geli,Yu, Xuan,Zhang, Fei,Mao, Duobin
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p. 225 - 232
(2013/10/21)
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- Enantioselective silylcyanation of aldehydes catalyzed by new chiral oxovanadium complex
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Oxovanadium(V) complex 4 was prepared from VOSO4 and tridentate Schiff base ligand, which was prepared from substituted salicylaldehyde and inexpensive (S)-valine. Asymmetric silylcyanation of the aldehydes catalyzed by catalyst 4 afforded cyanohydrins with good enantioselectivities.
- Chu, Chang-Ying,Hsu, Chu-Tin,Lo, Po Hsiang,Uang, Biing-Jiun
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scheme or table
p. 1981 - 1984
(2012/03/10)
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- METHOD FOR PRODUCING OPTICALLY ACTIVE CYANOHYDRIN COMPOUND
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A method of producing an optically active cyanohydrin compound represented by formula (3) (wherein, Q1 and Q2 are as defined below, and * represents that the indicated carbon atom is the optically active center) comprising reacting an aldehyde compound represented by formula (2) (wherein, Q1 and Q2 represent each independently a hydrogen atom, optionally substituted alkyl group having 1 to 6 carbon atoms, or the like) with hydrogen cyanide in the presence of a silyl compound and an asymmetric complex which is obtained by reacting an optically active pyridine compound represented by formula (1) (wherein, R1 and R2 represent each independently a hydrogen atom, alkyl group having 1 to 6 carbon atoms, or the like, provided that R1 and R2 are not the same.) with an aluminum halide.
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Page/Page column 11-12
(2011/01/11)
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- Immunoassay development for the class-specific assay for types I and II pyrethroid insecticides in water samples
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Five generic haptens of pyrethoid insecticides, which were classified as three types, were designed and synthesized: the first (hapten 1) is for type I pyrethroids without a cyano group, the second (hapten 2 and XQ) for type II pyrethroids with a cyano group, and the third (hapten 4 and 5) for both types of pyrethroids with loss of the ester group. The hapten structures were confirmed by MS and 1H-NMR. Hapten 1 and 2 were conjugated with BSA respectively and haptens 1-5 were conjugated with OVA. Four polyclonal antisera were raised against BSA conjugates including a mixture conjugate, and twenty antibody/coating conjugate combinations were selected for studies of assay sensitivity and specificity for pyrethroids. The study revealed the best combination, which showed equal high sensitivities (I50 is around 0.02 μg mL-1) to both types of pyrethroids. The immunity results suggest that, with a mixture conjugates, a polyclonal antibody against a group of insecticides can be prepared for multi-residue assays.
- Zhang, Qi,Zhang, Wen,Wang, Xiuping,Li, Peiwu
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experimental part
p. 164 - 177
(2010/05/17)
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- Immobilized hydroxynitrile lyases for enantioselective synthesis of cyanohydrins: Sol-gels and cross-linked enzyme aggregates
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The hydroxynitrile lyases (HNLs) from Prunus amygdalus (paHNL), Manihot esculenta (MeHNL), and Hevea brasiliensis (HbHNL) were successfully immobilized in sol-gels. The cross-linked enzyme aggregate (CLEA) of HbHNL was also prepared. These immobilized enzymes and the commercial PaHNL- and MeHNL-CLEAs were employed for the enantioselective synthesis of cyanohydrins. The sol-gels were highly efficient at low catalyst loading and particularly stable towards the organic solvent (diisopropyl ether) and substrate/product deactivation. The stabilization effect was inconsistent for CLEAs of different HNLs and significant deactivation of PaHNL- and HbHNL-CLEAs in diisopropyl ether was observed. In contrast commercial MeHNL-CLEA proved to be a remarkably robust and efficient biocatalyst in diisopropyl ether.
- Cabirol, Fabien L.,Hanefeld, Ulf,Sheldon, Roger A.
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p. 1645 - 1654
(2007/10/03)
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- Molecular cloning, purification, and biochemical characterization of a novel pyrethroid-hydrolyzing esterase from Klebsiella sp. strain ZD112
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The gene encoding pyrethroid-hydrolyzing esterase (EstP) from Klebsiella sp. strain ZD112 was cloned into Escherichia coli and sequenced. A sequence analysis of the DNA responsible for the esfP gene revealed an open reading frame of 1914 bp encoding for a protein of 637 amino acid residues. No similarities were found by a database homology search using the nucleotide and deduced amino acid sequences of the esterases and lipases. EstP was heterologously expressed in E. coli and purified. The molecular mass of the native enzyme was approximately 73 kDa as determined by gel filtration. The results of sodium dodecyl sulfate - polyacrylamide gel electrophoresis and the deduced amino acid sequence of EstP indicated molecular masses of 73 and 73.5 kDa, respectively, suggesting that EstP is a monomer. The purified EstP not only degraded many pyrethroid pesticides and the organophosphorus insecticide malathion, but also hydrolyzed ρ-nitrophenyl esters of various fatty acids, indicating that EstP is an esterase with broad substrates. The Km for trans- and cis-permethrin and kcat/Km values indicate that EstP hydrolyzes both these substrates with higher efficiency than the carboxylesterases from resistant insects and mammals. The catalytic activity of EstP was strongly inhibited by Hg2+, Ag+, and ρ-chloromercuribenzoate, whereas a less pronounced effect (3-8% inhibition) was observed in the presence of divalent cations, the chelating agent EDTA, and phenanthroline.
- Wu, Pei C.,Liu, Yu H.,Wang, Zhuo Y.,Zhang, Xiao Y.,Li, He,Liang, Wei Q.,Luo, Na,Hu, Ji M.,Lu, Jia Q.,Luan, Tian G.,Cao, Li X.
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p. 836 - 842
(2007/10/03)
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- Highly regioselective Friedel-Crafts reactions of electron-rich aromatic compounds with pyruvate catalyzed by Lewis acid-base: Efficient synthesis of pesticide cycloprothrin
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An efficient synthesis of aromatic lactate esters is reported via highly regioselective Friedel-Crafts reactions of electron-rich aromatic compounds with pyruvate ester promoted by TiCl4 in the presence of basic Al 2O3. The utility of the reaction is shown by the efficient synthesis of the pesticide cycloprothrin in high yield.
- Si, Yu-Gui,Chen, Jun,Li, Fan,Li, Jin-Hua,Qin, Ye-Jun,Jiang, Biao
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p. 898 - 904
(2007/10/03)
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- Purification and characterization of a novel pyrethroid hydrolase from Aspergillus niger ZD11
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The pyrethroid pesticides residues on foods and environmental contamination are a public safety concern. Pretreatment with pyrethroid hydrolase has the potential to alleviate the conditions. For this purpose, a fungus capable of using pyrethroid pesticides as a sole carbon source was isolated from the soil and characterized as Aspergillus niger ZD11. A novel pyrethroid hydrolase from cell extract was purified 41.5-fold to apparent homogeneity with 12.6% overall recovery. It is a monomeric structure with a molecular mass of 56 kDa, a pl of 5.4, and the enzyme activity was optimal at 45°C and pH 6.5. The activities were strongly inhibited by Hg2+, Ag+, and p-chloromercuribenzoate, whereas less pronounced effects (5-10% inhibition) were observed in the presence of the remaining divalent cations, the chelating agent EDTA and phenanthroline. The purified enzyme hydrolyzed various insecticides with similar carboxylester. trans-Permethrin is the preferred substrate.
- Liang, Wei Q.,Wang, Zhuo Y.,Li, He,Wu, Pei C.,Hu, Ji M.,Luo, Na,Cao, Li X.,Liu, Yu H.
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p. 7415 - 7420
(2007/10/03)
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- Asymmetric cyanohydrin synthesis catalyzed by Al(salen)/triphenylphosphane oxide
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Various aldehydes undergo asymmetric trimethylsilylcyanation with (CH 3)3SiCN (TMSCN) in the presence of a chiral Al(salen) complex and Ph3PO as the catalyst. This is a double activation where Al(salen) plays the role of Lewis acd and POPh3 acts as a Lewis base. Various kind of aldehydes were subjected to the enantioselective addition of (CH3)3SiCN at temperatures between -40 °C and -50 °C. Hydrolysis of the adducts gave cyanohydrins with over 90 % yield and 80 % ee in most cases. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
- Kim, Sung Soo,Song, Dae Ho
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p. 1777 - 1780
(2007/10/03)
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- Asymmetric cyanosilylation of aldehydes catalyzed by novel organocatalysts
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A novel proline-based N,N′-dioxide, which is easily prepared from inexpensive chemicals, serves as an effective catalyst for enantioselective cyanosilylation of aldehydes in up to 73% ee. Georg Thieme Verlag Stuttgart.
- Wen, Yuehong,Huang, Xiao,Huang, Jinglun,Xiong, Yan,Qin, Bo,Feng, Xiaoming
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p. 2445 - 2448
(2007/10/03)
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- A new (R)-hydroxynitrile lyase from Prunus mume: Asymmetric synthesis of cyanohydrins
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A new hydroxynitrile lyase (HNL) was isolated from the seed of Japanese apricot (Prunus mume). The enzyme has similar properties with HNL isolated from other Prunus species and is FAD containing enzyme. It accepts a large number of unnatural substrates (benzaldehyde and its variant) for the addition of HCN to produce the corresponding cyanohydrins in excellent optical and chemical yields. A new HPLC based enantioselective assay technique was developed for the enzyme, which promotes the addition of KCN to benzaldehyde in a buffered solution (pH=4.5).
- Nanda, Samik,Kato, Yasuo,Asano, Yasuhisa
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p. 10908 - 10916
(2007/10/03)
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- The first encapsulation of hydroxynitrile lyase from Hevea brasiliensis in a sol-gel matrix
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A straightforward process for the encapsulation of HbHNL under low methanol conditions has been developed. By adding a sol, prepared by hydrolysis of TMOS/MTMS at pH 2.8 with continuous removal of methanol, to a stirred solution of the enzyme in a buffer at pH 6.5, at least 65% of the activity of the free enzyme could be recovered after the encapsulation. The aquagels were successfully used in the synthesis of (S)-cyanohydrins. Graphical Abstract.
- Veum, Lars,Hanefeld, Ulf,Pierre, Alain
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p. 10419 - 10425
(2007/10/03)
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- Development of β-hydroxyamide/titanium complexes for catalytic enantioselective silylcyanation of aldehydes
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A highly enantioselective addition of trimethylsilylcyanide to aldehydes catalyzed by chiral titanium complexes is described. The chiral titanium complexes were prepared in situ from Ti(OiPr)4 and β-hydroxyamide ligands, that could easily be synthesized from ketopinic acid and C2 symmetrical chiral diamines in a small number of steps. Graphical Abstract.
- Uang, Biing-Jiun,Fu, I-Pin,Hwang, Chyuan-Der,Chang, Chun-Wei,Yang, Chun-Tzu,Hwang, Der-Ren
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p. 10479 - 10486
(2007/10/03)
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- Enantioselective addition of trimethylsilyl cyanide to aldehydes catalysed by bifunctional BINOLAM-AlCl versus monofunctional BINOL-AlCl complexes
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A highly enantioselective cyanation of aldehydes takes place by using a bifunctional catalyst derived from 3,3′-bis(diethylaminomethyl) substituted binaphthol (BINOLAM) and dimethylaluminium chloride. The addition is of wide scope and runs best in toluene at temperatures ranging from -20 to -40°C, in the presence of 4 A? MS and triphenylphosphine oxide as additives. The (R)- or (S)-cyanohydrins result when using (S)- or (R)-BINOLAM-AlCl complexes, respectively. The valuable ligand can be recovered by simple extractive work-up and recycled without loss of efficiency (both in terms of chemical and stereochemical yields). This methodology is applied to the Shibasaki synthesis of epothilone A. All the evidence available for the BINOLAM-AlCl enantioselective addition of TMSCN to aldehydes call for the intervention of a hydrocyanation reaction, addition of a catalytic amount of hydrogen cyanide, generated in situ, to an aldehyde, followed by O-silylation. In order to determine the role of the basic amino groups of BINOLAM, comparative studies are carried out with the monofunctional 1,1′-binaphthol-derived complex BINOL-AlCl. Graphical Abstract.
- Casas, Jesús,Nájera, Carmen,Sansano, José M.,Saá, José M.
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p. 10487 - 10496
(2007/10/03)
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- Process for producing cyclopropanecarboxylates
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There is disclosed a process process for producing a cyclopropanecarboxylate of formula (1): 1which process comprises reacting cyclopropanecarboxylic acid of formula (2): 2with a monohydroxy compound of formula (3): R6OH??(3),in the presence of a catalyst compound comprising an element of to Group 4 of the Periodic Table of Elements.
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- 1,2-Diphenylethylenediamine linked chiral Ti(IV) complex - A new entry to the highly enantioselective silylcyanation of aliphatic and aromatic aldehydes
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Highly enantioselective silylcyanation of aliphatic and aromatic aldehydes was achieved by using a 1,2-diphenylethylenediamine linked chiral Ti(IV) complex as the catalyst.
- Chang, Chun-Wei,Yang, Chun-Tzu,Hwang, Chyuan-Der,Uang, Biing-Jiun
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- 'Gelozymes' in organic synthesis. Part 2: Candida rugosa lipase mediated synthesis of enantiomerically pure (S)-cyano(3-phenoxyphenyl)methyl butyrate
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Significant changes in enantioselectivity (E) have been observed when the butanoate ester of (±)-1-hydroxy-1-(3-phenoxyphenyl)acetonitrile was subjected to hydrolysis in acetate buffer (pH 4.5, E = 6.4) and alcoholysis with 1-butanol in hexane catalysed by Candida rugosa lipase (E = 45). Enantiomerically pure (S)-butanoate ester so obtained (e.e. 98.4%) was converted to the corresponding (S)-cyanohydrin using Pseudomonas cepacia (Amano Ps) gelozyme. This strategy overcomes the problem of separation of the unwanted (R)-ester from the (S)-cyanohydrin.
- Fadnavis, Nitin W.,Babu, Ravi Luke,Sheelu, Gurrala,Deshpande, Ashlesha
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p. 1695 - 1699
(2007/10/03)
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- Catalytic, asymmetric cyanohydrin synthesis mediated by lanthanide(III) chloride pybox complexes
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Complexes formed between lanthanide trichlorides and 2,6- bis(substituted-2-oxazolin-2-yl)pyridine (pybox) ligands are effective catalysts for the enantioselective addition of trimethylsilylcyanide (TMSCN) to a range of aldehydes.
- Aspinall, Helen C.,Greeves, Nicholas,Smith, Peter M.
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p. 1763 - 1766
(2007/10/03)
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- Development of an immunoassay for the pyrethroid insecticide esfenvalerate
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A competitive enzyme-linked immunosorbent assay was developed for the detection of the pyrethroid insecticide esfenvalerate. Two haptens containing amine or propanoic acid groups on the terminal aromatic ring of the fenvalerate molecule were synthesized and coupled to carrier proteins as immunogens. Five antisera were produced and screened against eight different coating antigens. The assay that had the least interference and was the most sensitive for esfenvalerate was optimized and characterized. The I50 for esfenvalerate was 30 ± 6.2 μg/L, and the lower detection limit (LDL) was 3.0 2+ 1.8 μg/L. The assay was very selective. Other pyrethroid analogues and esfenvalerate metabolites tested did not cross-react significantly in this assay. To increase the sensitivity of the overall method, a C18 sorbent-based solid-phase extraction (SPE) was used for water matrix. With this SPE step, the LDL of the overall method for esfenvalerate was 0.1 μg/L in water samples.
- Shan, Guomin,Stoutamire, Donald W.,Wengatz, Ingrid,Gee, Shirley J.,Hammock, Bruce D.
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p. 2145 - 2155
(2007/10/03)
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- BMPD, a novel C2-chiral 1,3-diketone ligand; synthesis and application to an asymmetric catalytic reaction
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The synthesis of BMPD, 1,3-bis(2-methylferrocenyl)-propane-1,3-dione, was achieved via the Claisen condensation of a homochiral ferrocenecarboxylate and an acetylferrocene derived from the same chiral formylferrocene. Several metal complexes were prepared to exemplify the complexation ability of BMPD. A BMPD-yttrium complex was found to act as a new catalyst for silylcyanation of aldehydes with remarkable efficiency. As little as 0.2 mol% of the complex catalyzed the reaction of benzaldehyde and cyanotrimethylsilane to afford the cyanohydrin in 95% yield with 87% ee.
- Abiko, Atsushi,Wang, Guo-Qiang
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p. 11405 - 11420
(2007/10/03)
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- Chemo-enzymatic synthesis of (S)-α-cyano-3-phenoxybenzyl alcohol
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A chemo-enzymatic process for the preparation of (S)-α-cyano-3- phenoxybenzyl alcohol (S-CPBA), an important intermediate in the synthesis of many pyrethroids, was developed. The process consists of four stages, including lipase-mediated resolution. The first stage, the synthesis of racemic α-cyano-3-phenoxybenzyl acetate (CPBAc) from m-phenoxybenzaldehyde (m-PBA) and sodium cyanide in the presence of a phase transfer catalyst, resulted in a 75% yield with 95% purity. The second key step is the resolution of the racemic ester by a highly enantioselective lipase from Pseudomonas sp. The immobilized enzyme carried out the transesterification reaction to nearly full conversion (46% out of 50%) with an enantiomeric excess of >96%. The enzymatic reaction was accomplished in a batch system as well as in a fluidized bed column. The reaction was found to be inhibited by accumulation of the product and to a lesser extent, by the aldehyde. The separation of the enantiomerically pure alcohol from the undesired ester was performed by chromatographic techniques, as well as by extraction with hexane. The final racemization step of the (R)-ester was easily attained with the use of triethylamine in diisopropyl ether or toluene. The process was shown to be feasible on a gram scale and shows potential for scale up.
- Fishman, Ayelet,Zviely, Michael
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p. 107 - 118
(2007/10/03)
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- Synthesis of (1R,cis,αS)-cypermethrine via lipase catalyzed kinetic resolution of racemic m-phenoxybenzaldehyde cyanohydrin acetate
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A technical scale preparation of optically active (1R,cis, αS)- cypermethrine 4 from racemic m-phenoxybenzaldehyde cyanohydrin acetate (RS)- 1 and (1R,cis)-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-carboxylic acid chloride (1R,cis)-3 is described. Key steps of the new procedure are a lipase catalyzed enantioselective transesterification of (RS)-1 with n-butanol and direct acylation of the mixture of (R)-1 and (S)-cyanohydrin (S)-2 with (1R,cis)-3 to give enantiomerically pure (1R,cis,αS)-4. The unchanged (R)-1 is removed from (1R,cis,αS)-4 by distillation, and is racemized with triethylamine to give (RS)-1 which is returned to the process. The total yield of (1R,cis,αS)-4 referred to (RS)-1 is 80%.
- Roos, Juergen,Stelzer, Uwe,Effenberger, Franz
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p. 1043 - 1049
(2007/10/03)
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- Examination and Enhancement of Enantioselective Autoinduction in Cyanohydrin Formation by Cyclo[ (R)-His- (R)-Phe]
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The cyclic dipeptide cyclo[(R)-His-(R)-Phe] (1) has been known since 1981 to catalyze the enantioselective formation of cyanohydrins from aldehydes and HCN. Although 1 has proved to be very effective in the production of optically active cyanohydrins, the precise structure of its catalytically active form remains unresolved. The reaction of 3-phenoxybenzaldehyde and HCN in the presence of 1 has also been shown to exhibit enantioselective autocatalysis: the product (S)-3-phenoxymandelonitrile reacts with 1 to form a new, more enantioselective catalytic species. It is now demonstrated that this autocatalytic phenomenon is general and that, furthermore, it can be used to improve the enantioselectivity of cyanohydrin formation for several problematic substrates. Upon addition of a small (8 mol %) quantity of (S)-mandelonitrile or (S)-3-phenoxymandelonitrile to these reactions, the enantioselectivity of cyanohydrin formation was improved by as much as 20% ee. This effect has been ascribed to the formation of a complex between the added (S)-cyanohydrin and 1 that exhibits superior enantioselectivity to 1, either alone or complexed to the cyanohydrins of problematic substrates. A mathematical model has been developed, on the basis of a two-state equilibrium between 1 and a complex of 1 and cyanohydrin and used to explain the enantioselective autoinduction phenomenon in terms of five parameters: rate constants for the production of (R)- and (S)-cyanohydrin by both 1 and its cyanohydrin complex and an association constant for the formation of a cyanohydrin complex by 1. Two versions of this model, based on monomeric and dimeric 1, have been evaluated in light of the available data. Examination of the results reveals that the complexes of 1 and many of the cyanohydrins studied are highly enantioselective catalysts but that the complexes of 1 and cyanohydrins are only weakly associated; moreover, the complexation of 1 with most cyanohydrins leaves the rate of cyanohydrin formation unchanged, though both autocatalysis and enantioselective poisoning have been observed as well.
- Kogut, Eugene F.,Thoen, Jason C.,Lipton, Mark A.
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p. 4604 - 4610
(2007/10/03)
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- Enzyme catalysed formation of (S)-cyanohydrins derived from aldehydes and ketones in a biphasic solvent system
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By employing a vigorously stirred two phase system aqueous buffer/organic solvent and using the hydroxynitrile lyase from Hevea brasiliensis as biocatalyst enantiopure (S)-cyanohydrins from aliphatic, unsaturated, aromatic and heteroaromatic aldehydes and methyl alkyl and methyl phenyl ketones are obtained in high yield and in general 98-99% enantiomeric excess.
- Griengl, Herfried,Klempier, Norbert,Poechlauer, Peter,Schmidt, Michael,Shi, Nongyuan,Zabelinskaja-Mackova, Antonina A.
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p. 14477 - 14486
(2007/10/03)
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- Development of Immunoassays for Type II Synthetic Pyrethroids. 1. Hapten Design and Application to Heterologous and Homologous Assays
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Immunoassays differing in selectivities for pyrethroid insecticides have been developed for the detection of type II pyrethroids, including deltamethrin, cypermethrin, and λ-cyhalothrin. Two approaches were employed in hapten synthesis to raise antibodies with different cross-reactions: (1) use of three spacer attachment points to offset different parts of molecules from the points of attachment and (2) use of linkers with and without bulky groups in the enzyme conjugate to reduce antibody affinities for the spacer arm in the immunoassay. The first approach resulted in the preparation of three series of haptens with a spacer attached (1) at the aromatic moiety of pyrethroid, (2) through the middle of the molecule, and (3) at the cyclopropane moiety. Haptens based on the derivatives of the pyrethroid metabolites were also prepared. The second approach involved the use of a linker with a bulky (cyclohexane ring) functionality for preparation of an enzyme conjugate. While most combinations of antibody and conjugate could be used in immunoassays for detection of deltamethrin in the 10-100 μg/L range, in most cases the limits of detection of the assays (for total isomers of a particular target pyrethroid) were lowered 10-50 fold by treatment of the pyrethroid standards with dilute alkali to produce a different isomer mix. Fifteen antisera prepared using 8 haptens were each screened with 14 peroxidase conjugates, and 26 antibody/conjugate combinations were selected for further study on the basis of the assay sensitivity, dynamic behavior, and specificity for deltamethrin, cypermethrin, and cyhalothrin. These immunoassays provided 50% inhibition of antibody binding (IC50) values between 1.5 and 4.2 μg/L of isomerized total deltamethrin and limits of detection of 0.2-0.7 μg/L. The most sensitive immunoassay for total deltamethrin was obtained using cypermethric acid-KLH as the immunogen and a conjugate based on a derivative of cypermethrin coupled through the middle of the molecule to peroxidase. These provided an IC50 of 2 μg/L and a limit of detection of 0.2 μg/L of isomerized total deltamethrin. However, no particular hapten design produced antisera of clearly superior sensitivity or specificity for deltamethrin. Differing cross-reactions with the closely related pyrethroids, deltamethrin, cypermethrin, and cyhalothrin, were obtained, and for several antibodies the cross-reaction as well as the limits of detection could be altered by varying the conjugate combinations. Each of the 12 antibody/enzyme conjugate combinations that sensitively detected deltamethrin were very stereospecific, detecting the αS, 1R cis, (DM1), and αR, 1R cis (DM2) isomers only; the assay sensitivity was greater for the latter isomer.
- Lee, Nanju,McAdam, David P.,Skerritt, John H.
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p. 520 - 534
(2007/10/03)
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- Development of an Enzyme-Linked Immunosorbent Assay for the Detection of the Pyrethroid Insecticide Fenpropathrin
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A competitive enayme-linked immunosorbent assay (ELISA) was developed for the quantitative detection of fenpropathrin [(RS)-α-cyano-3-phenoxybenzyl-2,2,3,3-tetramethylcyclopropanecarboxylate]. Polyclonal antisera were isolated from rabbits immunized with two different fenpropathrin hapten conjugates. One hapten contained an amino function; the other contained a carboxyl group for conjugation to carrier proteins. Mollusk hemocyanins, thyroglobulin, and fetuin were used as carrier proteins. The antisera varied greatly in their affinities for fenpropathrin. A homologous assay system using the coating antigen format was the most sensitive. The IC50 for fenpropathrin was 20 μg/L, and the lower detection limit was 2.5 μg/L. Pyrethroids, such as phenothrin, permethrin, resmethrin, fenvalerate, deltamethrin, cyfluthrin, and cypermethrin, and the pyrethroid metabolites, 3-phenoxybenzoic acid and fenpropathrin acid, did not cross-react significantly in this assay. Ten percent acetone or methanol and a pH of 4 were determined to be optimum assay conditions. Various cationic, anionic, and nonionic detergents had no significant effect on the assay.
- Wengatz, Ingrid,Stoutamire, Donald W.,Gee, Shirley J.,Hammock, Bruce D.
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p. 2211 - 2221
(2007/10/03)
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- Preparation of optically active cyanohydrins using the (S)-hydroxynitrile lyase from Hevea brasiliensis
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Several aliphatic, aromatic and heteroaromatic aldehydes have been converted into the chiral cyanohydrins using the (S) hydroxynitrile lyase from Hevea brasiliensis. The corresponding cyanohydrins were obtained in moderate to good yield and high enantiomeric excess with the exeption of phenyloxyacetaldehyde, benzyloxyacetaldehyde and the pyrrole-, pyridine- and indolealdehydes investigated. In contrast to previously reported results, cinnamaldehyde could be converted into (S)-(-)-2-hydroxy-4-phenyl-(E)-but-3- enenitrile with good selectivity by means of optimized reaction conditions.
- Schmidt, Michael,Herve, Stephanie,Klempier, Norbert,Griengl, Herfried
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p. 7833 - 7840
(2007/10/03)
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- Asymmetric Carbon-Carbon Bond Forming Reactions Catalyzed by Chiral Schiff Base-Titanium Alkoxide Complexes
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The enantioselective addition of trimethylsilyl cyanide to a variety of aldehydes proceeded by the aid of a catalyst prepared in situ from titanium tetraisopropoxide and chiral Schiff bases and gave the corresponding cyanohydrins in high optical yield (up to 96percent e.e.).A remarkable rate enhancement was brought about by the addition of the Schiff base to the titanium alkoxide mediated silylcyanation of aldehydes.This catalyst system also promoted the highly enantioselective reaction of diketene with aldehydes, which led to the formation of optically active 5-hydroxy-3-oxoesters.
- Hayashi, Masahiko,Inoue, Tetsuya,Miyamoto, Yasunori,Oguni, Nobuki
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p. 4385 - 4398
(2007/10/02)
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- Synthetic applications of optically active cyanohydrins. Enantioselective syntheses of the hydroxyamides tembamide and aegeline, the cardiac drug denopamine, and some analogues of the bronchodilator salbutamol
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The natural hydroxyamides, (-)-tembamide and (-)-aegeline, and the cardiac drug (-) -denopamine have been prepared in homochiral form in good overall yield (>65%) from para - methoxy or para-allyloxybenzaldehyde by synthetic sequences involving entantioselective hydrocyanation of the aldehydes. Similar chemistry has been used to prepare analogues of the bronchodilator (-)-salbutamol both in high yield and with good enantiomeric excess.
- Brown, Roger F. C.,Donohue, Andrew C.,Roy Jackson,McCarthy, Tom D.
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p. 13739 - 13752
(2007/10/02)
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- Cyanohydrination process
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A process for the assymetric cyanohydrination of m- phenoxybenzaldehyde with HCN, using a catalytically effective amount of enantiomeric cyclo(phenylalanylhistidine) absorbed on a solid support comprising a nonionic polymer resin is described.
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- Enantioselective Trimethylsilylcyanation of Some Aldehydes Catalyzed by Chiral Schiff Base-Titanium Alkoxide Complexes
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A variety of aldehydes (aromatic, heteroaromatic, α,β-unsaturated, and nonconjugate aliphatic aldehydes) has been trimethylsilylcyanated in highly enantiomeric excess (ee) with a catalyst prepared in situ from titanium tetraisopropoxide and chiral Schiff bases.A remarkable rate enhancement was brought about by the addition of the Schiff base into the titanium alkoxide mediated silylcyanation of aldehydes.The chemical structure of chiral Schiff base-titanium alkoxide complexes is discussed based on their 13C NMR spectra, field desorption (FD) mass spectra, and molecular weights.
- Hayashi, Masahiko,Miyamoto, Yasunori,Inoue, Tetsuya,Oguni, Nobuki
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p. 1515 - 1522
(2007/10/02)
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- Aliphatic (S)-Cyanohydrins by Enzyme Catalyzed Synthesis
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The enzyme catalyzed synthesis of aliphatic (S)-cyanohydrins has been accomplished for the first time by application of a hydroxynitrile lyase from leaves of Hevea brasiliensis.The optical purities of (S)-cyanohydrins obtained are in a range between 60 - 97percent.
- Klempier, Norbert,Griengl, Herfried,Hayn, Marianne
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p. 4769 - 4772
(2007/10/02)
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- One-Pot Synthesis of Optically Active Cyanohydrin Acetates from Aldehydes via Lipase-Catalyzed Kinetic Resolution Coupled with in Situ Formation and Racemization of Cyanohydrins
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A novel one-pot synthesis of optically active cyanohydrin acetates from aldehydes has been accomplished by lipase-catalyzed kinetic resolution coupled with in situ formation and racemization of cyanohydrins in an organic solvent.Racemic cyanohydrins 2, generated from aldehydes 1 and acetone cyanohydrin in diisopropyl ether under the catalysis of basic anion-exchange resin (OH- form), were acetylated stereoselectively by a lipase from Pseudomonas cepacia (Amano) with isopropenyl acetate as an acylating reagent.The (S)-isomer of 2 was preferentially acetylated by the lipase, while the unreacted (R)-isomer was continuously racemized through reversible transhydrocyanation catalyzed by the resin.These processes thus enabled one stage conversion of various aldehydes 1a-n into the corresponding (S)-cyanohydrin acetates 3a-n with up to 94 percent ee in 63-100 percent conversion yields.The racemization of the optically active cyanohydrin 2e by Amberlite IRA-904 (OH- form) was found to be much faster then the enzymatic acetylation, confirming the effective second-order asymmetric transformation.Enzymatic deacetylation of (S)-cyanohydrin acetates in an organic solvent and the synthesis of optically active pyrethroids are also described.
- Inagaki, Minoru,Hiratake, Jun,Nishioka, Takaaki,Oda, Jun'ichi
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p. 5643 - 5649
(2007/10/02)
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- Peptide-titanium complex as catalyst for asymmetric addition of hydrogen cyanide to aldehyde
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The complex of titanium ethoxide and an acyclic dipeptide ester whose terminal amino group is modified to a salicylal-type Schiff base catalyzes the asymmetric addition of hydrogen cyanide to aldehydes with high enantioselectivity. In the reaction of benzaldehyde and hydrogen cyanide, (R)-mandelonitrile is obtained with an enantiomeric excess of 90% when N-((2-hydroxy-1-naphthyl)methylene)-(S)-valyl-(S)-tryptophan methyl ester is employed. In place of the dipeptide, the amide derivatives of an amino acid modified by substituted salicylaldehyde, such as N-(3,5-dibromosalicylidene)-(S)-valine piperidide, exhibit an entirely opposite stereoselectivity to yield S-cyanohydrins with optical purities up to 97% ee. This novel peptide-titanium complex, therefore, enables us to afford optically active cyanohydrins of both absolute configurations by using natural S-amino acids as chiral auxiliaries.
- Nitta, Hideaki,Yu, Donghai,Kudo, Masanobu,Mori, Atsunori,Inoue, Shohei
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p. 7969 - 7975
(2007/10/02)
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- Process for preparing optically active cyano compound
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A novel process for effectively preparing an optically active cyanohydrin comprising asymmetrically cyanating an aldehyde by reacting the aldehyde with a cyanating agent in the presence of a titanate of an optically active tartaric acid derivative.
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- Asymmetric Hydrocyanation of 3-Phenoxybenzaldehyde Catalyzed by Poly(chinona alkaloid-co-acrylonitrile)s
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Asymmetric addition of hydrogen cyanide to 3-phenoxybenzaldehyde catalyzed by poly(quinidine-co-acrylonitrile) affords (S)-2-hydroxy-2-(3'-phenoxyphenyl)acetonitrile in a moderate optical yield.
- Danda, Hidenori,Chino, Kunitake,Wake, Shigeo
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p. 731 - 732
(2007/10/02)
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- Peptide-metal complex as an asymmetric catalyst. A catalytic enantioselective cyanohydrin synthesis
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An acyclic dipeptide ester, 2-hydroxy-1-naphthylideneimino-(S)-valyl-(S)-tryptophane methyl ester (1a: Nap-S-Val-S-Trp-OMe), whose terminal amino group is modified to a Schiff base, is designed as a chiral auxiliary of an asymmetric catalyst. The mixture of 1 with titanium alkoxide catalyzes enantioselective hydrocyanation of benzaldehyde to afford optically active (R)-mandelonitrile with stereoselectivities up to 96:6.
- Mori,Nitta,Kudo,Inoue
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p. 4333 - 4336
(2007/10/02)
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- Enantioselective Hydrolysis of α-Cyano-3-phenoxybenzyl Acetate with Arthrobacter Lipase
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Lipase-catalyzed enantioselective hydrolysis of the acetic ester of racemic α-cyano-3-phenoxybenzyl alcohol (CPBA) was examined to prepare (S)-CPBA.Most of the lipases tested hydrolyzed (S)-CPBA acetate preferentially, while Candida cylindracea lipase favored (R)-CPBA acetate.Enantioselective hydrolysis by Arthrobacter lipase gave optically pure (S)-CPBA in the reaction mixture of pH 4.0.The kinetic studies showed that (R)-CPBA acetate reacted as a competitive inhibitor.The Arthrobacter lipase solution in the water/oil biphasic reaction system could be usedrepeatedly.The lipase immobilized to resins had insufficient activity or low operational stability with the repeated batch reaction.The unhydrolyzed (R)-CPBA acetate was racemized by heating with triethylamine and could be reused as the substrate of enzymatic hydrolysis.A chemico-enzymatic process for the preparation of (S)-CPBA was developed based on these studies.
- Mitsuda, Satoshi,Yamamoto, Hidefumi,Umemura, Takeaki,Hirohara, Hideo,Nabeshima, Shigeyasu
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p. 2907 - 2912
(2007/10/02)
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- Novel cyclopropane carboxylates
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Novel 2,2-dimethyl-cyclopropane carboxylic acid derivatives of the formula STR1 wherein X1 and X2 are individually halogen, R1 is selected from the group consisting of halogen, alkyl of 1 to 8 carbon atoms, optionally substituted aryl of 6 to 14 carbon atoms, perfluoroalkyl of 1 to 8 carbon atoms, --CN and STR2 R' is alkyl of 1 to 8 carbon atoms, Y is selected from the group consisting of --SO2 Alk1, --SO2 Ar, STR3 Alk1 is optionally unsaturated alkyl of 1 to 8 carbon atoms no substituted or substituted with at least one functional group, Ar is aryl of 6 to 14 carbon atoms no substituted or substituted with at least one functional group, Alk2 and Alk3 and Alk2 ' and Alk3 ' are optionally unsaturated alkyl of 1 to 8 carbon atoms no substituted or substituted with at least one functional group or together with STR4 form the rings STR5 wherein A is optionally unsaturated alkyl of 1 to 6 carbon atoms optionally substituted with at least one functional group, R is alkyl of 1 to 6 carbon atoms no substituted or substituted with at least one functional group or aryl of 6 to 14 carbon atoms no substituted or substituted with at least one functional group and R is selected from the group consisting of hydrogen, alkyl of 1 to 8 carbon atoms and residue of an alcohol used in pyrethrinoid esters having pesticidal activity.
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- The Cyclic Dipeptide cyclo as a Catalyst for Asymmetric Addition of Hydrogen Cyanide to Aldehydes
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cyclo (cyclo, 1) catalyzes the addition of hydrogen cyanide to benzaldehyde in toluene at -20 deg C to afford (R)-mandelonitrile with enantiomeric excess of 97 percent in high yield. cyclo gives (S)-mandelonitrile. cyclo (1) exhibits a broad substrate specificity, and a variety of aldehydes (3a-r) such as m-methoxybenzaldehyde (3c), 6-methoxy-2-naphthaldehyde (3k), and isobutyraldehyde (3o) similarly afforded the corresponding cyanohydrins with high enantiopurities (97 percent ee for 3c, 93 percent ee for 3k, 71 percent ee for 3o). (R)-Mandelonitrile thus obtained was successfully converted to various chiral synthons such as mandelic acid (7), methyl mandelate (8), and 2-amino-1-phenylethanol (9) without any racemization.
- Tanaka, Kenzo,Mori, Atsunori,Inoue, Shohei
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p. 181 - 185
(2007/10/02)
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