bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resolution Method of Two Sets of Binding Sites for the Cationic Surfactant–Urease Interaction
Authors: Saboury Ali Akbar , Borbar Abdoul Khalegh , Moosavi-Movahedi Ali Akbar 
Published: June 2006

Abstract
The binding of a homologous series of cationic surfactants with jack-bean urease has been studied by equilibrium dialysis at pH = 10 and 27 °C. The unusual concavity of a Scatchard plot has been interpreted by using the binding capacity concept. The relation between the binding capacity and the criterion of cooperativity (Hill coefficient) was obtained, and in the base of this relation a new method has been introduced for the resolution and characterization of two sets of binding sites in these systems, which is supported by microcalorimetric and spectroscopic data.
Photocatalyzed Production of Hydrogen and Iodine from Aqueous Solutions of Iodide Using Platinum-Loaded TiO2 Powder
Authors: Ohno Teruhisa , Saito Susumu , Fujihara Kan , Matsumura Michio 
Published: June 2006

Abstract
Hydrogen evolution and oxidation of iodide on photoirradiated Pt-loaded TiO2 powder were studied in the deaerated solutions containing iodide ions. These photocatalytic reactions have been considered to be difficult because the reaction is endothermic and reversible. However, we found that under some experimental conditions the reactions proceeded until the concentration of I3− ions reached a limiting level. The initial rate of the reactions and the limiting concentration of I3− ions in solution were enhanced as the pH of the solution decreased. In order to elucidate the pH dependence, the anodic current due to the oxidation of iodide ions on TiO2 film electrodes and the adsorptivity of iodide ions on TiO2 powder were measured. The results showed that the enhanced reactivity at low pH is due to the increased adsorptivity of iodide ions on TiO2. It was also found that the electric contact between platinum and TiO2 is important to make the reactions go forward.
Theory of Thermo- and Photo-Chemical Reactivity and Its Applications
Authors: Aono Shigeyuki 
Published: June 2006

Abstract
A theory of the chemical reactivity for thermo- and photo-chemical reactions is formulated in terms of the Green’s function and applied to recent observations: the photo-magnetization of a molecular crystal obtained by reduction from 2,2′-biindenyl observed by Tanaka et al., and the internal rotation of the methyl group in toluene and o-, m-, and p-fluorotoluenes observed by Ito et al.
β–α Photoisomerization of Cobaloxime Complexes in the Solid State. 5. Reaction Rate Reduced by a Hydrogen Bond
Authors: Amano Hiroki , Sekine Akiko , Ohashi Yuji , Hagiwara Mieko , Sato Junko , Arai Yoshifusa , Ohgo Yoshiaki 
Published: June 2006

Abstract
The crystal structures of three cobaloxime complexes with different axial base ligands have been analyzed by X-ray analysis at room temperature. I: (2-Cyanoethyl)bis(dimethylglyoximato)((S)-phenylalaninol)cobalt(III); the crystal is orthorhombic, the space group being P212121, Z = 4 with a = 9.416(3), b = 27.184(3), c = 9.184(3) Å. II: (2-Cyanoethyl)bis(dimethylglyoximato)((S)-phenyl-alanine methyl ester)cobalt(III); the crystal is monoclinic, the space group being P21, Z = 4 with a = 14.376(2), b = 11.988(2), c = 14.874(1) Å, and β = 101.05(1)°. III: (2-Cyanoethyl)bis(dimethylglyoximato)(methyldiphenylphosphine)cobalt(III); the crystal is monoclinic, the space group being P21/n, Z = 4 with a = 11.558(4), b = 15.542(3), c = 14.393(5) Å, and β = 91.02(4)°. The structures were refined by the full-matrix least-squares method to final R values of 0.041, 0.052, and 0.044 for 2340, 3287, and 4400 observed reflections, respectively. The photoisomerization rates of I, II, and III in the solid state were obtained from the changes in the IR spectra. The rate of I was insignificantly small, but the rates of II and III were calculated to be 0.1 × 10−4 and 1.9 × 10−4 s−1, respectively, assuming first-order kinetics. The 2-cyanoethyl groups in the three complex crystals take perpendicular conformations to their cobaloxime planes. The 2-cyanoethyl group of I makes a hydrogen bond with the N–H group of the neighboring molecule. The non-reactivity of I may be brought about by the hydrogen bond.
Structural and Magnetic Studies of Dimeric Copper(II) 2,2-Diphenylpropanoato and Triphenylacetato Complexes with Oxygen-Donor Ligands. The Cage Geometry of Dimeric α-Phenyl Substituted Copper(II) Carboxylates
Authors: Steward Omar W , Johnston Brian S , Chang Shih-Chi , Harada Akihiko , Ohba Shigeru , Tokii Tadashi , Kato Michinobu 
Published: June 2006

Abstract
The syntheses, structures, and magnetic properties of copper(II) carboxylates with bridging α-phenyl substituted carboxylato ligands and unidentate oxygen-donor ligands are reported: Cu2 (O2CCPh2Me)4(acetone)2 (1), triclinic , a = 15.441(4), b = 15.602(4), c = 12.790(2) Å, α = 106.52(2), β = 92.11(2), γ = 96.38(2)°, V = 2928(1) Å3, Z = 2, −2J = 352 cm−1; [Cu2(O2CCPh2Me)4(H2O)2]·H2O (2), triclinic , a = 13.895(2), b = 14.717(2), c = 7.318(1) Å, α = 95.67(1), β = 101.71(1), γ = 68.12(1)°, V = 1359.3(4) Å3, Z = 1, −2J = 344 cm−1; [Cu2(O2CCPh2Me)4(EtOH)2]·EtOH (3), monoclinic P21/c, a = 26.927(5), b = 9.152(3), c = 26.881(5) Å, β = 115.02(1)°, V = 6003(2) Å3, Z = 4, −2J = 347 cm−1; [Cu2(O2CCPh3)4(Ph3CCO2H)2]·CH2Cl2 (4), monoclinic P21/c, a = 18.133(8), b = 23.046(7), c = 25.013(7) Å, β = 101.01(3)°, V = 10268(5) Å3, Z = 4; [Cu2(O2CCPh3)4(H2O)2]·4H2O (5a), tetragonal , a = 18.451(6), c = 10.703(7) Å, V = 3643(3) Å3, Z = 2; [Cu2(O2CCPh3)4(H2O)2]·2H2O (5b), tetragonal , a = 18.224(2), c = 10.776(5) Å, V = 3578(1) Å3, Z = 2, −2J = 292 cm−1; and Cu2(O2CSiPh3)4(EtOH)2 (6), monoclinic C2/c, a = 21.811(3), b = 17.366(3), c = 21.221(4) Å, β = 91.19(1)°, V = 8036(2) Å3, Z = 4, −2J = 1193 cm−1. The factors which influence the cage and coordination sphere geometry in dimeric α-phenyl substituted copper(II) carboxylates are discussed based on the above structures and the reported structures with unidentate nitrogen- and oxygen-donor ligands. In 4 and 5, intramolecular steric effects between the bulky triphenylacetato ligands result in a considerable distortion of the cage geometry. The distortion of the coordination sphere geometry around copper(II) in the complexes from square pyramidal toward trigonal bipyramidal reduces the spin-exchange interaction.
Magnetic Properties of Some Triangular Trinuclear Complexes of [Ru2M(μ-CH3COO)6(μ3-O)(py)3]n+ with a Paramagnetic Ion M
Authors: Kobayashi Hanako , Uryû Norikiyo , Mogi Iwao , Miyamoto Ryo , Ohba Yasunori , Iwaizumi Masamoto , Sasaki Yoichi , Ohto Akihiro , Suwabe Masaaki , Ito Tasuku 
Published: June 2006

Abstract
Magnetic susceptibilities and electron paramagnetic resonances (EPRs) of coordination compounds of triangular trinuclear [Ru2M(μ-CH3COO)6(μ3-O)(py)3]n+, M = Mn(II), Fe(III), Cr(III), Ni(II), or Co(II) ions, were observed. The results were analysed by the spin vector model. Effective Bohr magneton numbers showed that the main superexchange interaction within each cluster was of the order of J/k = −300 K. This was considered to be working through μ3-O. Together with some weaker superexchange interactions through μ-CH3COO paths, fittings with the susceptibilities of the model were tried. EPR signals at temperatures of a few K were characteristic of each M ion. M = Mn(II) and M = Fe(III) were at high spin states of S = 5/2 and M = Co(II) was at a low spin state of S = 1/2. Temperature dependences of EPR signals are discussed.
Complexes of Hard Metal Ions with Amine-N-polycarboxylates as Fluoride Receptors
Authors: Yuchi Akio , Hokari Norihisa , Terao Hirohito , Wada Hiroko 
Published: June 2006

Abstract
The equilibria were systematically studied in the reaction of hard metal complexes (Mm+: Al3+, Zr4+, Hf4+, Th4+; HnL: amine-N-polycarboxylic acid) with fluoride. Mixed-ligand complexes were found in most systems; each metal ion shows a critical ligand having a necessary and sufficient number of donor atoms to lose the metal ion affinity for fluoride. The ML complexes of ligands containing a fewer number of donor atoms than the critical ligands have high affinities for fluoride. Among them, the zirconium(IV) complex of N-methyliminodiacetic acid is an excellent fluoride receptor; fluoride is quantitatively fixed on the complex at −log [H+] &lt; 4.5 and is reversibly expelled at −log [H+] &gt; 9 within a short time.
Comparative Study of the Visible Spectra of the Iron(III) Complexes of para-Substituted Tetraphenylporphyrins. Electronic Effects of Substituents and Axial Ligands
Authors: Ohya Toshie , Sato Mitsuo 
Published: June 2006

Abstract
The visible absorption spectra of the high-spin iron(III) complexes of the tetra-para-substituted derivatives of 5,10,15,20-tetraphenylporphyrin, Fe(p-Rtpp)X (R = OMe, H, F or Cl; X = Cl, Br or I), have been compared with each other in order to clarify the electronic effects of the phenyl substituents and axial ligands. Two charge-transfer bands shift to higher energy as the electron-withdrawing ability of the substituents increases. This is attributed to a stabilization of the porphyrin a1u(π) and a2u(π) orbitals involved in the electronic transition. These bands shift to lower energy in the order X = Cl &lt; Br &lt; I; the energies of these bands for I are the lowest of the three. By considering the predominantly ionic character of the bond between Fe and X, it has been proved that the iron dyz and dzx levels are lowered in this order, thereby causing a red shift. The Qv porphyrin transition shifts to lower energy in the order X = Cl &lt; Br &lt; I, and the Q0 transition exhibits the same trend to a less extent. These results are explained by taking into consideration two kinds of effects of axial ligands: the electron–electron repulsion in the porphyrin ring and the porphyrin skeletal vibrations.
Syntheses and Properties of Extremely Stable Di(1-azulenyl)phenylmethyl and (1-Azulenyl)diphenylmethyl Cations Having Dimethylamino Substituents on Their Phenyl Groups
Authors: Ito Shunji , Kobayashi Hiroki , Kikuchi Shigeru , Morita Noboru , Asao Toyonobu 
Published: June 2006

Abstract
A series of extremely stable di(1-azulenyl)phenylmethyl and (1-azulenyl)diphenylmethyl cations having dimethylamino substituents on their phenyl groups, i.e., di(1-azulenyl)[4-(dimethylamino)phenyl]methyl (5a) and (1-azulenyl)bis[4-(dimethylamino)phenyl]methyl (6a) cations and their 3-methyl-1-azulenyl (5b and 6b) and 3,6-di-t-butyl-1-azulenyl (5c and 6c) homologs, were synthesized by hydride abstraction from the corresponding hydrides. Their properties were fully characterized. As expected, the pKR+ values of these cations dramatically increased with the dimethylamino substituents on their phenyl groups. The values of 5a—c (pKR+ 13.2—13.8) and 6a—c (pKR+ 12.6—13.3) are higher by 1.4—2.7 and 8.7—9.6 pK units than those of the corresponding analogous phenyl- and diphenylmethyl cations. The redox behavior of each cation was also affected by the substituents. The oxidation of 5a—c in acetonitrile exhibited a barely separated two-step oxidation wave at potential ranges of +0.75 — +0.87 and +0.89 — +1.01 V vs. Ag/Ag+ upon cyclic voltammetry (CV), as occurs in the oxidation of tri(1-azulenyl)methyl cations. The wave is ascribed to the oxidation of the two azulene rings to generate a trication species. The oxidation of 6a—c also showed two waves at a narrow potential range at +0.74 — +0.92 V. Although the reduction of 6a—c exhibited an irreversible wave at −0.94 V, that of 5a—c showed a reversible wave at −0.87 — −0.95 V upon CV. The temperature-dependent 1H NMR spectra of 5b and 6b were also examined to clarify their stereochemistries. Stereoisomerizations due to the pyramidal dimethylamino substituents in addition to the propeller conformations of three aromatic rings were observed by low-temperature NMR studies. At higher temperature the NMR reflects the rapid isomerization of these stereoisomerisms.
Preparation of Pyrimidinophanes from Pyrimidine Bases
Authors: Itahara Toshio 
Published: June 2006

Abstract
Treatment of pyrimidine bases such as uracil, thymine, and 5-fluorouracil with X(CH2)nX (X = I or Br; n = 4—12) gave three types of pyrimidinophanes. When the numbers of carbon atoms of X(CH2)nX are odd numbers (n = 5, 7, 9, 11), three structures of pyrimidinophanes could be differentiated on the basis of the 13C NMR and mass spectra. Treatment of pyrimidinophanes with 1,4-naphthoquinone or maleimides in the presence of palladium(II) acetate gave the coupling products. Reaction of pyrimidinophanes with NaNO2 in the presence of palladium(II) acetate led to the nitration.
Conformational Locking by Intramolecular Hydrogen Bonding and Unlocking by Solvation Using 7-Vinylnorcaradienes
Authors: Kohmoto Shigeo , Koyano Ichiro , Kawatsuji Teruyuki , Kasimura Hideaki , Kishikawa Keiki , Yamamoto Makoto , Yamada Kazutoshi 
Published: June 2006

Abstract
Norcaradiene derivatives 1, 5-(1-benzyloxycarbonyl-2-methyl-1-propenyl)-3-oxatricyclo[4.4.0.01,5]deca-7,9-dien-4-one, showed a restricted rotation in the 1H NMR spectra. VT 1H NMR measurements in CDCl3 revealed the existence of two rotamers at low temperature with ΔG≠ of 11.5 (250 K), 12.1 (263 K), and 13.9 kcal mol−1 (296 K) for norcaradienes with R = H, Me, and t-Bu, where R is the para substituent of the benzyloxy group, respectively. This restricted rotation was stopped in CDCl3 at ambient temperature by introducing intramolecular hydrogen bonding via reducing of the lactone moiety to the corresponding lactols. The observed conformational locking due to the intramolecular hydrogen bonding was unlocked by solvation, resulting in the formation of three conformers in methanol-d4 and dimethyl-d6 sulfoxide. VT 1H NMR measurements of the lactol derivative in dimethyl-d6 sulfoxide showed that two of the conformers interconverted with ΔG≠ of 17.4 kcal mol−1.
Restricted Rotation Involving the Tetrahedral Carbon. LXIII. Endeavor toward Enhancing the Rotational Barrier in 9-s-Alkyltriptycenes
Authors: Oki Michinori , Fukuda Taizo , Asakura Mitsuhiro , Toyota Shinji 
Published: June 2006

Abstract
In order to enhance barriers to rotation about the C9-substituent bond in 9-s-alkyltritpycenes, the secondary alkyl group was modified as well as the peri-substituent. The barrier was slightly enhanced by modifying the substituents but the extent was rather limited. This limitation was attributed to the limitation of the ways of preparation of 9-s-alkyltriptycenes that should give three stable rotamers and carry substituents at peri-positions, where only 1,8-difluoro substituents could be used.
Gas-Phase Substituent Effects in Highly Electron-Deficient Systems. I. Intrinsic Stabilities of 1-Aryl-1-(trifluoromethyl)ethyl Cations
Authors: Mishima Masaaki , Inoue Hiroki , Itai Shingo , Fujio Mizue , Tsuno Yuho 
Published: June 2006

Abstract
The relative stabilities of 1-aryl-1-(trifluoromethyl)ethyl cations were determined by measuring the proton-transfer equilibria of 1-aryl-1-(trifluoromethyl)ethylenes or the chloride-transfer equilibria of 1-aryl-1-(trifluoromethyl)ethyl chlorides in the gas phase. The stability of 1-phenyl-1-(trifluoromethyl)ethyl cation was found to be 16 kcal mol−1 lower than that of the α-cumyl (1-phenyl-1-methylethyl) cation. The substituent effect on the stability of this cation can be correlated in terms of the Yukawa–Tsuno equation, giving an r+ of 1.41 and a ρ of −10.0 (in log K/Ko−1 unit). While the ρ value is nearly identical to that of the α-cumyl cation series, the r+ value is remarkably higher than the value of unity for the α-cumyl cation, indicating that such a highly electron-deficient carbocation system should be characterized by an extremely large r+ value compared with that of the stable α-cumyl cation. In addition, this r+ value agrees with that for the SN1 solvolysis of 1-aryl-1-(trifluoromethyl)ethyl tosylates. Such agreement of the r+ values between the gas phase and solvolysis reactions has been generally observed for the benzylic carbocation systems. It is concluded that the enhanced r+ value for the solvolysis of 1-aryl-1-(trifluoromethyl)ethyl tosylates must reflect the intrinsic resonance demand characteristic of the parent 1-phenyl-1-(trifluoromethyl)ethyl cation, itself, and that the extremely large ρ+ values given by a simple correlation with σ+ (r+ = 1) are an artifact due to an improper analysis of underestimating the resonance demand for such highly deactivated substrates.
Synthesis of Imidazole-Containing Ligands and Studies on Metal Complexes
Authors: Yamagiwa Yoshiro , Koreishi Yoshiro , Kiyozumi Satoshi , Kobayashi Masanori , Kamikawa Tadao , Tsukino Mitsuji , Goi Hironori , Yamamoto Mikiko , Munakata Megumu 
Published: June 2006

Abstract
1,5-Di(imidazol-1-yl)-3-[2-(imidazol-1-yl)ethyl]pentane, 1,7-di(imidazol-1-yl)-4-[3-(imidazol-1-yl)propyl]heptane, N,N′,N″-tris[2-(imidazol-4-yl)ethyl]benzene-1,3,5-tricarboxamide, and 1,3,5-tris[3-(imidazol-1-yl)propyl]benzene (TIPB) have been synthesized for a study of the formation and characteristics of zinc complexes. TIPB forms a crystalline zinc complex, not a tetrahedral complex but an octahedral complex. Other ligands form either microcrystalline complexes or polymer complexes with zinc.
Photoinduced Electron-Transfer Reaction of (Phenylazo)triphenylmethane (PAT). Behavior of Generated Trityl Cation
Authors: Miyagawa Nobukazu , Karatsu Takashi , Futami Yasuo , Kunihiro Takeshi , Kiyota Atsushi , Kitamura Akihide 
Published: June 2006

Abstract
The decomposition mechanism of photoinduced electron transfer (PET) between electron deficient sensitizers and (phenylazo)triphenylmethane (PAT) was investigated. In 9,10-dicyanoanthracene (DCA) sensitized reaction, benzene, triphenylmethane, 3,3,3-triphenylpropionitrile, and [4-(diphenylmethyl)phenyl]acetonitrile were obtained, and the product distribution was the same as for the direct photolysis and the thermolysis. In the case of 2,4,6-triphenylpyrylium tetrafluoroborate (TPP+) sensitization, the product distribution was drastically changed and 9-phenylfluorene was found to be one of the main products. The results of the irradiation wavelength effects indicate that 9-phenylfluorene is produced by the photoreaction of a trityl cation which is generated by the decomposition of a radical cation of PAT. The results of the experiments of laser flash photolysis suggest that the rate of back electron transfer between a radical anion of the sensitizer and a trityl cation plays an important role in these reactions.
Syntheses of 3,4-Disubstituted 2-Tosylpyrroles and 5-Tosyl-1,5-dihydro-2H-pyrrol-2-ones Starting from Ethyl 3,4-Disubstituted 2-Pyrrolecarboxylates
Authors: Murata Yasue , Kinoshita Hideki , Inomata Katsuhiko 
Published: June 2006

Abstract
The syntheses of 3,4-disubstituted 2-tosylpyrroles and 5-tosyl-1,5-dihydro-2H-pyrrol-2-ones were accomplished via 3,4-disubstituted 2-iodo-5-tosylpyrroles starting from ethyl 3,4-disubstituted 2-pyrrolecarboxylates.
Reactivities of Stable Rotamers. XXXVIII. Reaction of Chlorine with 1-(9-Fluorenyl)-2-(1-methylethenyl)naphthalene Rotamers: Outstanding Solvent Effects on Product Distribution and Ritter Type Reactions in Acetonitrile
Authors: Oki Michinori , Hirose Takanori , Aki Michihiko , Morita Nobuhiro , Nose Emiko , Kataoka Yasukazu , Ono Masaru , Toyota Shinji 
Published: June 2006

Abstract
Reactions of the olefinic moiety of the title compounds with chlorine were done as carbon tetrachloride, nitromethane, and acetonitrile solutions. The ap-isomer afforded a mixture of the corresponding addition product and olefins that are derived by deprotonation of the intervening chloro-carbocation. The product distribution was strongly affected by the solvents, although chlorinated olefins are the main products in carbon tetrachloride. The sp-isomer yielded the chloro-olefins that are rotationally isomeric with these compounds in carbon tetrachloride. No cyclized compound, which is expected if the attack of the intermediate cation on a benzene ring closely located to it takes place, was detected under these conditions. By contrast, the reaction in nitromethane resulted in formation of the cyclized compound as a major product from the sp isomer. In acetonitrile, the reaction afforded the cyclized compound in a fair yield from the sp, but that of the ap isomer gave products that were derived by the Ritter type reactions, in addition to those observed in other solvents. The results are attributed to the stability of the intervening cations in these solvents. In the Ritter type reaction, the first evidence that deprotonation from the intervening acetonitrilium ion to produce a ketene imine was obtained. The bromine addition to the olefinic bond in the sp-isomer of the title compound revealed that the solvent seriously affects the yields of the cyclic compound as well as the ratios of two bromo-olefins.
Effect of Acid Deposition on Urban Dew Chemistry in Yokohama, Japan
Authors: Okochi Hiroshi , Kajimoto Takuya , Arai Yukiko , Igawa Manabu 
Published: June 2006

Abstract
Dews or frosts formed on artificial collectors were collected during the early morning in Yokohama in 1993 and 1994 and analyzed for weak acids as well as major inorganic ions. In 1993 (n = 21) the dew pH ranged from 3.23 to 7.12 and averaged 4.60; in 1994 (n = 56) it ranged from 4.11 to 7.74 and averaged 5.41. Based on the average, NH4+ and Ca2+ were major cations (423 and 178 μequiv L−1 for NH4+ and Ca2+ in 1993, respectively, and 454 and 274 μequiv L−1 in 1994, respectively) and SO42− was the dominant anion (344 μequiv L−1 in 1993 and 271 μequiv L−1 in 1994) in dew water. The dew chemistry was characterized by relatively high concentrations of weak acid anions, particularly hydrogensulfite ion (HSO3−). Dew water sometimes had very high acidity (the minimum pH was 3.23 during the period of this research), which might have been due to the aqueous oxidation of S(IV). From a resistance model calculation, the S(IV) concentration in dew water was suggested to be influenced by the dissolution of HCHO from the atmosphere and the subsequent formation of HMSA.
Effect of Pressure on Subtilisin Catalysis: Hydrolysis and Peptide Synthesis
Authors: Kunugi Shigeru , Kobayashi Ichizo , Takano Kazuya , Murakami Yukiko 
Published: June 2006

Abstract
The effects of high pressure on the subtilisin (Carlsberg) catalyzed hydrolysis and aminolysis reactions were investigated.
The pH dependence of the apparent second-order rate constant (kcat/Km(app)) for N-glutaryl–Ala–Ala–Pro–Leu–pNA showed a slightly lowered profile due to increasing pressure. The pressure dependence (up to 150 MPa) of kcat/Km(app) for this substrate or N-benzyloxycarbonyl–Gly–Gly–Leu–pNA at a constant pH (8.5) showed slightly positive activation volumes: + 2—3 ml mol−1.
The substrate concentration dependence of the hydrolytic rate for N-succinyl–Ala–Ala–Pro–Phe–pNA showed increased slope and Y-intercept on an Eadie plot at 150 MPa; the reaction volume for the 1/Km was positive and the activation volume for kcat was estimated to be negative. Pressure affected the two parameters in the opposite directions, and as a result, the effect on kcat/Km(app) became rather small.
Pressure promoted the subtilisin-catalyzed transacylation reaction between Fua–Phe–OMe and GlyNH2, but the fraction of the peptide formation (fa) decreased slightly under high pressure. Pressure seemed to accelerate the hydrolytic process much more, especially the nucleophile-assisted hydrolysis of the acyl-enzyme, than the acyl-transfer to the nucleophile.