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Diphenyl (α-aminoalkyl)phosphonates act as mechanism-based inhibitors against serine proteases by forming a covalent bond with the hydroxy group of the active center Ser residue. Because the covalent bond was found to be broken and replaced by 2-pyridinaldoxime methiodide (2PAM), we employed a peptidyl derivative bearing diphenyl 1-amino-2-phenylethylphosphonate moiety (Phe(p) (OPh)2 ) to target the active site of chymotrypsin and to selectively anchor to Lys175 in the vicinity of the active site. Previously, it was reported that the configuration of the α-carbon of phosphorus in diphenyl (α-aminoalkyl)phosphonates affects the inactivation reaction of serine proteases, i.e., the (R)-enantiomeric diphenyl phosphonate is comparable to l-amino acids and it effectively reacts with serine proteases, whereas the (S)-enantiomeric form does not. In this study, we evaluated the stereochemical effect of the phosphonate moiety on the selective chemical modification. Epimeric dipeptidyl derivatives, Ala-(R or S)-Phe(p) (OPh)2 , were prepared by separation with RP-HPLC. A tripeptidyl (R)-epimer (Ala-Ala-(R)-Phe(p) (OPh)2 ) exhibited a more potent inactivation ability against chymotrypsin than the (S)-epimer. The enzyme inactivated by the (R)-epimer was more effectively reactivated with 2PAM than the enzyme inactivated by the (S)-epimer. Finally, N-succinimidyl (NHS) active ester derivatives, NHS-Suc-Ala-Ala- (R or S)-Phe(p) (OPh)2 , were prepared, and we evaluated their action when modifying Lys175 in chymotrypsin. We demonstrated that the epimeric NHS derivative that possessed the diphenyl phosphonate moiety with the (R)-configuration effectively modified Lys175 in chymotrypsin, whereas that with the (S)-configuration did not. These results demonstrate the utility of peptidyl derivatives that bear an optically active diphenyl phosphonate moiety as affinity labeling probes in protein bioconjugation. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 521-530, 2016.

Aims Food-derived peptides have been reported to yield a variety of health promoting activities. Pyroglutamyl peptides are contained in the wheat gluten hydrolysate. In the present study, we investigated the effect of pyroglutamyl dipeptides on the lipopolysaccharide (LPS)-induced inflammation in macrophages. Main methods RAW 264.7 macrophages were treated with LPS and various concentrations of pyroglutamyl-leucine (pyroGlu-Leu), -valine (pyroGlu-Val), -methionine (pyroGlu-Met), and -phenylalanine (pyroGlu-Phe). Cell viability/proliferation and various inflammatory parameters were measured by the established methods including ELISA and western blotting. The binding of fluorescein isothiocyanate-labeled LPS to RAW 264.7 cells was also measured fluorescently. Key findings All the tested dipeptides significantly inhibited the secretion of nitric oxide, tumor necrosis factor (TNF)-α, and interleukin (IL)-6 from LPS-stimulated RAW 264.7 macrophages. Above all, pyroGlu-Leu inhibited the secretion of all these inflammatory mediators even at the lowest dose (200 μg/ml). PyroGlu-Leu dose-dependently suppressed IκBα degradation and MAPK (JNK, ERK, and p38) phosphorylation in LPS-stimulated RAW 264.7 cells. On the other hand, it did not affect the binding of LPS to the cell surface. Significance Our results indicated that pyroGlu-Leu inhibits LPS-induced inflammatory response via the blocking of NF-κB and MAPK pathways in RAW 264.7 macrophages.

To establish a covalent chromatography system for purification of naturally occurring chymotrypsin-like serine proteases, a diphenyl 1-amino-2-phenylethylphosphonate derivative bearing Gly-Gly-Gly as a spacer was immobilized on the Sepharose 4FF gel. In this system, bovine chymotrypsin was selectively bound to the phosphonate immobilized on the gel and then released by the action of 2-pyridinealdoxime methiodide as the reactivated enzyme. Based on the study results for selective binding and reactivation conditions, chymotrypsin-like proteases from pancreatin (hog pancreas) were rapidly and highly purified within three hours. Keywords

For site-selective chemical modification in the vicinity of the active site of chymotrypsin (Csin), a peptide derivative 1 bearing a diphenyl 1-amino-2-phenylethylphosphonate moiety for targeting t...

Glutathione (GSH) is the most prevalent low-molecular-weight thiol in mammalian cells and is crucial for antioxidant defense, nutrient metabolism, and the regulation of pathways essential for whole body homeostasis. GSH transport systems have been identified in the membranes of various tissues and organs, including the small intestine. However, little is known regarding GSH transport across intestinal epithelial cells. The current in vitro and ex vivo uptake study of GSH demonstrated that intact GSH can be transported across intestinal epithelial cells, suggesting that GSH uptake is not proton-dependent. It would appear that the initial uptake of GSH into cells is a rapid process. Furthermore, the visualized GSH after 60 min of transport by MALDI-MS imaging showed localization of intact GSH inside the intestinal wall. In vivo study found that ingested (13)C-GSH was rapidly converted to GSSG and accumulated in red blood cells and liver, but was little present in plasma. The ingested GSH has potent nutraceutical benefits for human health to improve oxidative stress and defense in human.

A kinetic investigation on the hydrolysis of aryl(fluoro)(phenyl)-λ6-sulfanenitriles was carried out in some aqueous and mixed aqueous-organic solutions. The pH-rate profiles showed that the hydrolysis consists of pH-independent, acid-catalyzed and base-catalyzed reactions. The neutral hydrolysis of fluoro-λ6-sulfanenitriles was found to proceed via an SN1 or an S-nitrilosulfonium cation-like transition state, which is characterized by a large negative Hammett ρ-value (ρ = −1.76 in water; −1.85 in CH3CN/H2O(1/4, v/v); −2.35 in TFE/H2O (1/1, v/v)), relatively large m-values (ca. 0.83 for fluoro(diphenyl)-λ6-sulfanenitrile; ca. 0.82 for fluoro(p-nitrophenyl)(phenyl)-λ6-sulfanenitrile against the solvent ionizing power YOTs-values in acetonitrile–water), a common ion effect in TFE/H2O, and a small salt effect. The large negative activation entropies (−60 – −101 J K−1 mol−1) were presumed to be due to strong solvation of F− with H2O in the reaction systems. The ease of ion dissociation of the S–F bond was exa...

A Ralstonia sp. strain JC-64 that is capable of accumulating poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P[3HB-co-3HV]) from cottonseed oil and valeric acid was isolated. By using a high limiting-nitrogen (HLN) mineral medium as the medium for the second stage of the fermentation process and by adding the two carbon sources at different times, a range of copolymers with 12–62 mol% of 3HV were produced from a series of HLN mineral mediums containing different compositions of cottonseed oil and valeric acid by Ralstonia sp. JC-64. The melting temperature (T m ) of polyhydroxybutyrate from cottonseed oil was 174°C and that of P(3HB-co-3HV) with the highest 3HV-mol fraction (62%) was 81°C.

The soil bacterium Bacillus cereus Tim-r01 efficiently transformed polyaromatic carboxylic acids (PACA) such as 4-biphenylcarboxylic acid (4-BPCA), 4-biphenylacetic acid, and 4-phenoxybenzoic acid into their corresponding amides. The amidation activity was expressed at 37 degrees C (pH 7-8) in the presence of grown cells in nutrients under an aerobic atmosphere. Other strains of B. cereus, IFO 3001 and IAM 1229, also gave the amide from 4-BPCA. In phosphate-buffered saline (PBS), the addition of normal amino acids was essential, while sulfur-containing amino acids such as methionine and cysteine drastically inhibited the amidation. Tracer experiments using N-15-isoleucine and N-15-alanine showed that the nitrogen atom of the amide came from an amino group of amino acids but not from ammonia or alkylamines.

Two groups of irreversible serine peptidase inhibitors, peptidyl chloromethyl ketones and peptidyl phosphonate diphenyl esters, were examined for antitrypanosomal activity against the bloodstream form of Trypanosoma brucei brucei. Both peptidyl chloromethyl ketones and peptidyl phosphonate diphenyl esters inhibited trypsin-like peptidases of the parasites and exhibited antitrypanosomal activity at micromolar concentrations. In live T. b. brucei, labelled analogues of both of these groups of inhibitors primarily targeted an 80-kDa peptidase, possibly a serine oligopeptidase known as oligopeptidase B. In an in vivo mouse model of infection, one of these inhibitors, carbobenzyloxyglycyl-4-amidinophenylglycine phosphonate diphenyl ester, was curative at 5 mg kg−1 day−1 but appeared toxic at higher doses. There was no significant correlation between the inhibitory potency (as evaluated against purified T. b. brucei oligopeptidase B) and the in vitro antitrypanosomal efficacy of either group of inhibitors, suggesting that these inhibitors were acting on multiple targets within the parasites, or had different cell permeability properties. These findings suggest that serine peptidases may represent novel chemotherapeutic targets in African trypanosomes.

Diphenyl(diphenylsulfodiimidoyl)(nitrido)sulfur(VI) (2) and diphenyl(diphenylsulfoximidoyl)(nitrido)sulfur(VI) (3) (Ph2XSNSNPh2N, X=NH, O) were prepared by the reaction of diphenyl(fluoro)(nitrido)sulfur(VI) (Ph2FSN) with sodium salts of diphenyl-sulfodiimide (Ph2S(NH)2) and -sulfoximide (Ph2OSNH). The nitrido-sulfur complexes 2 and 3 are considerably basic (pKa=7.86 and 7.60, respectively). Treatment of 2 and 3 with perchloric acid afforded quantitatively the corresponding μ-aza-bis[diphenyl(imido)sulfur(V)] perchlorate (4) and μ-aza-[diphenyl(imido)]-[diphenyl(oxo)]disulfur(V) perchlorate (5) ([Ph2XSNSPh2NH]+[ClO4]−, X=NH, O). The crystal structures of 4 and 5 were determined by X-ray crystallographic analysis. The former has essentially C2 symmetry with an SNS bond angle of 120.3(2)°, bridging SN bond lengths of 1.595(3) and 1.604(3) A, and terminal SN bond lengths of 1.509(3) and 1.497(3); the latter cation is an unsymmetrically substituted oxygen analog with an SNS bond angle of 123.1(2)°, and bridging SN bond lengths of 1.607(4) and 1.568(4) A, terminal SN and SO bond lengths of 1.501(3) and 1.438(2) A. Single-point ab initio calculations were also carried out using the data from the crystal structures of 4 and 5.

The hydrolysis of alkoxy(aryl)(phenyl)-λ6-sulfanenitriles in several buffer solutions was found to follow a good pseudo-first-order kinetic equation, giving the corresponding sulfoximides and alcohols (for the case of the hydrolysis of neopentyloxy-λ6-sulfanenitrile, giving a rearranged product, 2-methyl-2-butanol). The dependence of the rate of hydrolysis on the structure of the alkyl group showed the opposite trend to the usual SN2 character, i.e. Me < Pr < Bu ≈ Et < i–Pr, except for neopentyl. The pH-rate profiles indicated that the rate of hydrolysis is also first order in [H+] at pH more than 6.08, and trends to saturate at low pH. According to these kinetic results, a two-step reaction mechanism was proposed which involves a pre-equilibrium protonation on the nitrogen atom of the alkoxy-λ6-sulfanenitriles, followed by a rate-determining C-O bond cleavage via an SN2 or SN1 mechanism on the alkyl carbon atom depending on the structure of the alkyl group. From a double-reciprocal plot of 1/kobs vs. 1/[...

To develop a simple method to determine the degree of substitution (dS) for starch ester, we prepared starch acetate with various dS values (0—3) and examined the mode of starch-iodine complex formation for the starch acetate by monitoring the ultraviolet-visible (UV-vis) spectra and their Fourier-transform infrared (FT-IR) spectral changes. The effect of acetylation on the formation of the starch-iodine complex was investigated by monitoring the decrease in absorbance at 680 nm (blue value). The blue value decreased by increasing the standard dS value determined by NMR for starch acetate, but two different correlations between the blue values and the dS values were observed for the low- and highly-substituted starch acetate. The FT-IR spectra for starch acetate particles were measured using a diffuse reflection method. The peak areas and absorbances of the bands assigned to the acetyl group showed a poor correlation with standard dS values from the NMR. On the other hand, the FT-IR peaks assigned to sodi...

Previously we reported the novel thioaldehydes generation via thermolyses of phenacyl sulfoxides bearing some heteroaromatics. Thermolysis of sulfoxides (1a,b and 2a-4a) bearing other heterocycles such as thiadiazole, triazole, and tetrazole in the presence of 2,3-dimethyl-1,3-butadiene in dioxane at 100 degrees C led to the unexpected products 6-substituted-5,6-dihydro-3,4-dimethyl-2H-thiapyran 1-oxide (5a,b). These products were considered to be formed by the Diels-Alder reaction of the diene with the sulfines formed initially by the thermal decomposition of the sulfoxides. The rate acceleration and the improvement of the yield by addition of 1.5 equiv of triethylamine, especially in the case of ethoxycabonylmethyl sulfoxide 1c, was observed. The cis-trans selectivity for sulfine cycloadducts was also studied by NMR spectrometry. The reactions of alpha-substituted phenacyl sulfoxides 1d-f bearing a phenyl-substituted tetrazolyl group in the presence of the same diene were also studied.

In the study of the thermolysis of heteroaryl substituted sulfoxides, we examined the same reaction in the presence of several amines, such as aniline, benzylamine, and morpholine. In the case of 5-(1-phenyl)-1,2,3,4-tetrazolylsulfinylmethyl(dimethyl)phosphine oxide ( 1 ), the corresponding phosphinecarbothioamide 2 were unexpectedly obtained in moderate yields together with 1-phenyl-1,2,3,4-tetrazole ( 3 ). These products are considered to be formed by the addition reaction of amines to the sulfine formed initially and then elimination of H 2 O.

The thermal decomposition of melamine produces melame and meleme, while alkaline hydrolysis of melamine produces ammeline and ammelide. These four melamine derivatives were determined by high-performance cation-exchange chromatography using phosphate buffer as the eluent. The elution behavior during the isocratic and gradient elutions was examined and the determination was simultaneously achieved using photodiode array UV–Vis detection. An isocratic elution with 50 mM phosphate buffer (pH 2.5) seemed most suitable for the rapid and quantitative analysis. Three types of gradient elutions involving phosphate- and NaCl-concentrations, and pH also showed satisfactory separations for the melamine derivatives.

The protective effect of guanidine hydrochloride (Gu-HCl) on the retrogradation of waxy corn starch (WCS) gel was studied using differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR), and solid-state 1H nuclear magnetic resonance (NMR). The areas of the endothermic peaks on DSC curves attributed to re-gelatinization of WCS gels became small and shifted to lower temperature with increasing Gu-HCl contents; finally, the endothermic peak for WCS gel containing 40% Gu-HCl disappeared, indicating that the WCS gel remained in the gelatinized state. The solid-state 1H NMR and FT-IR spectra for retrograded WCS gels showed significant changes compared with those for gelatinized WCS gels. In the process of retrogradation, these spectral changes should imply the formation of intra- and intermolecular hydrogen bonds of WCS and the increase of free water molecules. However, the 1H NMR and FT-IR spectra for a WCS gel containing 40% Gu-HCl did not show such changes along with the progre...

The pyrolysis of triphenyl (diphenoxyphosphinyl)phosphorimidate ( 1 ) was investigated using differential thermal analysis-thermogravimetry (DTA-TG), thermogravimetry-mass spectrometry (TG-MS), infrared spectroscopy (IR), mass spectrometry (MS), high performance liquid chromatography (HPLC) and the 31 P nuclear magnetic resonance method ( 31 P NMR). The cleavage of 1 by electron impact (EI) was also investigated, the results were used to elucidate the pyrolysis process. Compound 1 decomposed on heating to form phenol, triphenyl phosphate, hexaphenoxycyclotriphosphazene, octaphenoxycyclotetraphosphazene, triphenyl [ N -(diphenoxyphosphinyl)- P , P -diphenoxyphosphinimyl]phosphorimidate and longer-chain phosphazene compound (PhO) 2 P(O)NP(OPh) 2 NP(OPh) 2 NP(OPh) 3 . In mass spectrometric analysis, 1 was cleaved by the elimination of a phenoxyl radical, similar to pyrolysis, the formation of the ion assigned to triphenyl phosphate was observed.

粉末X線回折とフーリエ変換赤外分光分析(FT-IR)を用いて研究した.粘度は保存期間とともに増加した.一方,糊化前にGu-HC1を添加しても粘度は保存期間とともに増加し,添加量が多いほど粘度は低かった.膨潤した粒子の相互作用により,それら粒子は水素結合により網目構造を形成する.デソプンの粘度の増加率の長期的な増加は可逆的な結晶化と,貯蔵中の粒子間内の分子間水素結合と関係する.そこでこれらの老化した糊液のX線回折を測定すると,B型の結晶構造の回折線が観測された.また糊化直後と老化後の糊液のFT-IRを測定すると,水素結合を示す3000-3800cm-1の波数でピークの相違を観測し,五つのピークがこの波数内で重なり合っていた.これらの結果から老化の際に,Gu-HC1がワキシコーンスターチの分子構造に与える変化を提案し,模式図として示した.

Combustion tests show that polyamide-6 (PA-6) mixed with melamine is self-extinguishing. The thermal degradation process in PA-6 is modified strongly by the presence of melamine, so that the temperature of decomposition is lowered and the composition of the resulting volatile products is changed. On the other hand, melamine is not effective for either polypropylene (PP) or low-density polyethylene (LDPE). Activation energies based on thermogravimetry (TG) curves for the thermal decomposition of each sample at different heating rates are in the range of about 88.1 to 263 kJ mol −1 . The fluctuations found in activation energies indicates that a charring mechanism may contribute to the overall process. Minor amounts of thermal decomposition products other than ϵ-caprolactam were also evolved from the pure PA-6, their formation being suppressed in mixtures with melamine. The charring process occurs in parallel with the volatilization of decomposition products of PA-6, on which melamine seems not to have a significant effect. It appears evident that, compared with PP and LDPE, PA-6 is much more susceptible to thermal decomposition in the presence of melamine.

Meleme, one of thermal decomposition products of melamine, ws analyzed satisfactorily by high-performance cation-exchange chromatography using 20 m M phosphate buffer as eluent. The elution behavior of meleme and melamine at various pH values (pH 2.0–6.0) was examined and the determination was accomplishes simultaneously using photodiode array UV-Vis detection.

The thermal decomposition and mass spectra of the N-phenyl- (1), N,N′-diphenyl- (2), and N,N′,N′-triphenylphosphoric triamides (3) were investigated. DTA-TG/DTG, TG-TRAP-GC/MS measurements, IR spectroscopic analyses, mass spectrometric analyses, HPLC analyses, and a kinetic study were carried out to investigate the thermal decomposition. From the analytical results, it was suggested that 1 decomposed while liberating ammonia and aniline, and condensed in several stages; its thermal products at about 160 °C contained 2. Compound 2 decomposed and condensed to form some condensed products at about 200 °C; its thermal products also contained 3. Compound 3 decomposed while liberating aniline to form a cyclic dimer, while the existence of other thermal products was also observed; the cyclic dimer further pyrolyzed in several stages, and 1 and 2 formed a similar condensed product in the 400 to 500 °C temperature range, though that for 3 was different. In addition, the apparent activation energy of the thermal de...

ポリアミド系樹脂に対し非常に有効な防燃剤であるメラミンシアヌレートの熱分解について研究を行った。メラミンシアヌレートは加熱により徐々に水素結合が伸び, 360℃ 付近でその水素結合の一部が切断される。この温度では,メラミンシアヌレートから対応する等モル量のメラミンとシアヌル酸が生じるわけではない。メラミンシアヌレートの熱分解はアソモニア,水,二酸化炭素,シアン酸,メラミソ,シアヌル酸のような揮発,または昇華化合物の形成を導く。これらのほかに揮発成分としてシアン酸アンモニウムやメラミンシアヌレートの形成が確認された。シアン酸アンモニウムはメラミソシアヌレートから直接生じたのではなく,熱分解で生じたアンモニアとシアン酸との気相反応によるものである。一方,メラミンシアヌレートはそれ自身が昇華して形成したのではなく,熱分解により発生したメラミンとシアヌル酸の気相反応で生じたものである。また,残留したメラミンシアヌレートは 420-450℃ で縮合し, 450℃ 以上で非晶質体へと転換した。メラミンシアヌレートの熱分解挙動を結晶構造,熱分解生成物の観点から議論した。

ワキシコーンスターチ糊液の老化を示差走査熱量測定(DSC)と粉末 X 線回折を用いて研究した。DSC は -15℃ から 15℃ ,および 30 から 100℃ の温度範囲で測定した。糊化直後の糊液では 0℃ 付近に鋭い吸熱ピークが観測され,これ以外に吸熱は観測されなかった。長期放置して糊液が老化すると 50℃ 付近に再糊化の吸熱ピークが観測され,また 0℃ 付近の吸熱ピークは二つに分かれた。これら両者の吸熱ピークは互いに関連しており,ともに老化の結果であると考えられる。一方,糊液を凍結させて放置したところ, 72 日経過しても老化に起因する吸熱ピークは観測されなかった。また,老化した糊液中のワキシコーンスターチの X 線回折を測定すると B 型の結晶構造の回折線が観測された。また 3 種類の濃度の糊液を調製し,老化挙動を比較したところ,老化の速度は著しく影響を受けたのに対し,デンプン乾物量換算した吸熱量はほぼ一定の値になった。このことは糊液老化の機構が濃度により影響を受けないことを示している。これらの結果から糊化,老化の際のワキシコーンスターチの分子構造の変化を提案し,模式図として示した。

Reaction of 2-methyl-2-propanesulfenic acid (1) with methyl arenesulfenates (2) gave S-aryl 2-methyl-2-propanethiosulfinates quantitatively, and kinetic investigation was carried out. Second-order rate dependence (first-order in methyl benzenesulfenate (2a) and first-order in the sulfenic acid (1)) was observed, and a small activation enthalpy (ΔH‡ = 28 kJ mol−1) and a large negative activation entropy (ΔS‡ = −130 J K−1 mol−1) were obtained. Kinetics for the reaction of trans-decalin-9-sulfenic acid (3) with the sulfenates 2 under acidic conditions in methanol–water gave the observation of the second-order dependence, a small activation enthalpy (ΔH‡ = 30.5 kJ mol−1), a large negative activation entropy (ΔS‡ = −140 J K−1 mol−1), a large negative Hammett ρ-value (ρ = −1.39) and no solvent isotope effect (kMeOH/kMeOD = 1.10—1.14 in the range of 15.64—29.98 °C). Kinetics for acidic hydrolysis of the sulfenate 2 under the same conditions afforded the similar activation parameters (ΔH‡ = 40.7 kJ mol−1, ΔS‡ = −...

We synthesized N-(4-nitrophenyl)-6-aminohexanamide (AHpNA) and used it as a substrate in a kinetic study of 6-aminohexanoate-hydrolase (NylB), a nylon oligomer-hydrolyzing enzyme. NylBs derived from Arthrobacter sp. KI72 and Pseudomonas sp. NK87 hydrolyzed AHpNA as well as a 6-aminohexanoic acid dimer, a known substrate for NylB. The K(m) values of the NylB from Arthrobacter sp. KI72 and Pseudomonas sp. NK87 for AHpNA were 0.5 mM and 2.0 mM, respectively.

Antipsychotic-treated schizophrenia patients are susceptible to dyslipidemia. However, the results of previous studies of North American and UK populations including various races have been contradictory with regard to which lipid measure was the most affected in patients with schizophrenia taking antipsychotic agents. The aim of this study was to investigate the effect of schizophrenia patients receiving antipsychotic agents on each lipid measure in a Japanese population.The samples included 136 control individuals and 157 patients with schizophrenia treated with antipsychotic agents. Age, gender distribution and body mass index (BMI) of the controls were matched with the patients.The high-density lipoprotein cholesterol (HDL-cholesterol) levels were significantly lower in patients than in the control subjects (P.001). However, there were no significant differences in either the low-density lipoprotein cholesterol (LDL-cholesterol) or triglyceride levels between the patient and control groups. We performed a multiple linear regression analysis, and schizophrenia receiving antipsychotics was an independent predictor of decreased HDL-cholesterol. An increased BMI, male gender and cigarette smoking were also major predictors of a decreased HDL-cholesterol level (r(2)=0.42, P.001).At least in Japanese with schizophrenia receiving antipsychotic agents, the HDL-cholesterol levels should be closely monitored in all patients, even those who are not obese or do not smoke, to decrease their risk of cardiovascular disease.

Objectives There have been few reports regarding olanzapine (OLZ)-related QT prolongation and hyperprolactinemia. This study evaluated the dose-dependent effect of OLZ on QT interval and plasma prolactin (PRL) level in a single sample of patients with schizophrenia. Methods Twenty-six subjects treated with varying starting doses of OLZ were enrolled in the study. Following baseline assessments, which included completion of the Brief Psychiatric Rating Scale (BPRS), measurements of Body Mass Index (BMI), QT interval, electrolytes, fasting plasma glucose, PRL, hemoglobin A1c (HbA1c), total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL), and low density lipoprotein (LDL), the dose of OLZ was increased for each subject. The same parameters were evaluated following the increased dose treatment. Results A significant decrease was observed in BPRS score (p = 0.01) following treatment with an increased dose of OLZ. Significant increases were observed in BMI (p = 0.032), QTc (p = 0.031), and plasma PRL level (p = 0.028). The mean values of electrolytes, fasting plasma glucose, HbA1c, TC, TG, HDL and LDL treatment were unchanged by the switch to increased-dose OLZ treatment. Conclusion We have demonstrated the dose-dependent effect of OLZ on the QT interval and the plasma PRL level of patients with schizophrenia. Copyright © 2011 John Wiley & Sons, Ltd.

We have newly synthesized the non-symmetrical "phthalimidoyl active ester" bi-dentate cross-linking reagents having an acid chloride, 2-benzothiazole, or 1-benzotriazole group (i.e., 9, 15, and 16) on the basis of the reactivity study of the "active ester" model compounds, 11-14, toward the various nucleophiles and examined their reaction selectivity towards the same nucleophiles. Then, we applied for the modification of cholesterol at the more reactive site of the bi-dentate linkers to give 3β-cholesteryl 4-(phthalimidoyloxycarbonyl)butyrate (39), and the subsequent reaction of 39 with several amines, such as benzylamine, 4-chlorobenzylamine, 2-phenylethylamine, L-phenylalanine methyl ester, or diphenylalanine benzyl ester as a protein model of the cholesterol antigen.

Reaction of 2-methyl-2-propanesulfenic acid (1) with methyl arenesulfenates (2) gave S-aryl 2-methyl-2-propanethiosulfinates quantitatively, and kinetic investigation was carried out. Second-order rate dependence (first-order in methyl benzenesulfenate (2a) and first-order in the sulfenic acid (1)) was observed, and a small activation enthalpy (ΔH‡ = 28 kJ mol−1) and a large negative activation entropy (ΔS‡ = −130 J K−1 mol−1) were obtained. Kinetics for the reaction of trans-decalin-9-sulfenic acid (3) with the sulfenates 2 under acidic conditions in methanol–water gave the observation of the second-order dependence, a small activation enthalpy (ΔH‡ = 30.5 kJ mol−1), a large negative activation entropy (ΔS‡ = −140 J K−1 mol−1), a large negative Hammett ρ-value (ρ = −1.39) and no solvent isotope effect (kMeOH/kMeOD = 1.10—1.14 in the range of 15.64—29.98 °C). Kinetics for acidic hydrolysis of the sulfenate 2 under the same conditions afforded the similar activation parameters (ΔH‡ = 40.7 kJ mol−1, ΔS‡ = −...

N-Substituted S,S,S-triphenyliminosulfonium salts were prepared by the reaction of S,S,S-triphenylthiazyne with several electrophiles. The molecular structure of N-methyl-S,S,S-triphenyliminosulfonium perchlorate was determined by the X-ray crystallographic analysis. Furthermore, their reactivities were investigated.

In the study of the thermolysis of heteroaryl substituted sulfoxides, we examined the same reaction in the presence of several amines, such as aniline, benzylamine, and morpholine. In the case of 5-(1-phenyl)-1,2,3,4-tetrazolylsulfinylmethyl(dimethyl)phosphine oxide ( 1 ), the corresponding phosphinecarbothioamide 2 were unexpectedly obtained in moderate yields together with 1-phenyl-1,2,3,4-tetrazole ( 3 ). These products are considered to be formed by the addition reaction of amines to the sulfine formed initially and then elimination of H 2 O.

Previously we reported the novel thioaldehydes generation via thermolyses of phenacyl sulfoxides bearing some heteroaromatics. Thermolysis of sulfoxides (1a,b and 2a-4a) bearing other heterocycles such as thiadiazole, triazole, and tetrazole in the presence of 2,3-dimethyl-1,3-butadiene in dioxane at 100 degrees C led to the unexpected products 6-substituted-5,6-dihydro-3,4-dimethyl-2H-thiapyran 1-oxide (5a,b). These products were considered to be formed by the Diels-Alder reaction of the diene with the sulfines formed initially by the thermal decomposition of the sulfoxides. The rate acceleration and the improvement of the yield by addition of 1.5 equiv of triethylamine, especially in the case of ethoxycabonylmethyl sulfoxide 1c, was observed. The cis-trans selectivity for sulfine cycloadducts was also studied by NMR spectrometry. The reactions of alpha-substituted phenacyl sulfoxides 1d-f bearing a phenyl-substituted tetrazolyl group in the presence of the same diene were also studied.

In order to investigate the conformation and localization of lipopeptides in lipid bilayers, a basic model peptide with a long alkyl chain, Ac-Ser-Val-Lys-Amy-Ser-Trp-Lys-Val-NHCH3 Amy-1; Amy = alpha-aminomyristic acid) was synthesized. Its interaction with neutral and acidic phospholipid bilayers was studied by circular dichroism (CD) spectroscopy, dye leakage and fluorescence measurements. Another peptide, Ac-Leu-Ala-Arg-Leu-Trp-Amy-Arg-Leu-Leu-Ala-Arg-Leu-NHCH3 (Amy-2), which was prepared previously, was used for comparison. The CD data indicated that Amy-1 took a beta-turn and/or a beta-structure in the absence and presence of liposomes. Amy-2 formed a beta-structure in aqueous solution and an alpha-helical structure in liposomes. The dye leakage ability of Amy-1 was much weaker than that of Amy-2. Fluorescence spectroscopic data suggest that the peptides are immersed in lipid bilayers. Based on these results, discussion is made in terms of localization of the peptides in lipid bilayers.

Basic amphipathic alpha-helical peptides Ac-(Leu-Ala-Arg-Leu)3 or 4-NHCH3 (4(3) or 4(4)) and H-(Leu-Ala-Arg-Leu)3-(Leu-Arg-Ala-Leu)2 or 3-OH (4(5) or 4(6)) were synthesized and studied in terms of their interactions with phospholipid membranes, biological activity, and ion channel-forming ability. CD study of the peptides showed that they form alpha-helical structures in the presence of phospholipid liposomes and thus they have amphipathic distribution of the side chains along the axis of the helix. A leakage study of carboxyfluorescein encapsulated in phospholipid vesicles indicated that the peptides possess a highly potent ability to perturb the membrane structure. Membrane current measurements using the planar lipid bilayer technique revealed that the peptide 4(6), which was long enough to span the lipid bilayer in the alpha-helical structure, formed cation-selective ion channels at a concentration of 0.5 microM in a planar diphytanoylphosphatidylcholine bilayer. In contrast, other shorter peptides failed to form discrete and stable channels though they occasionally induced an increase in the membrane current with erratic conductance levels. The probability of detecting a conductance increase was in the order of 4(6) greater than 4(5) greater than 4(4) greater than 4(3), which corresponds to the order of the peptide chain lengths. Furthermore, 4(6) but not 4(5) showed an antimicrobial activity against both Gram-positive and -negative bacteria. The structure of ion channels formed by 4(6) and the relationship between the peptide chain length and biological activity of the synthetic peptides are discussed.

The antibacterial activities of CH3(CH2)nCO–(Leu–Ala–Arg–Leu)–3-NHCH3 (1, n=0; 2, n=3; 3, n=8; 4, n=14) and their interaction with phospholipid bilayers were examined. Their order in the antibacterial activity was 1>2>3>4 against Gram-positive bacteria and 2>1>3>4 against Gram-negative bacteria: the activity of 4 was essentially negative. The CD study indicated that the α-helical content of 3 and 4 was higher than that of 1 and 2. Peptides 1–3 effectively showed a dye-leakage ability, while the ability of 4 was weak. The DSC measurement indicated that the membrane-stabilizing effect of the acyl group in 4 fairly compensated for the destabilizing effect of the hydrophobic peptide moiety. These results imply that no antibacterial activity of 4 is correlated to a strong interaction of the acyl group in 4 with the acyl chain in DPPC to stabilize the membrane.

Basic amphipathic beta-structural peptides, Ac-(Ser-Val-Lys-Val)n-NHCH3 (1n, n = 1-3) and Ac-(Lys-Val)n-NHCH3 (2n, n = 2-4), were synthesized and their interaction with DPPC and DPPC-DPPG (3:1) bilayers was studied by CD, dye-leakage and fluorescence experiments. The CD data indicated that oligopeptides consisting of more than eight residues with alternating hydrophobic (Val) and hydrophilic amino acids (Ser and Lys) were able to form an amphipathic beta-structure in acidic phospholipid bilayers, but not or weakly in aqueous solution and in neutral phospholipid bilayers. The dye-leakage experiment showed that the basic amphipathic beta-structural peptides interact with acidic phospholipid bilayers to perturb them, but less effectively compared with basic amphipathic alpha-helical peptides. Fluorescent spectroscopic data suggest that hydrophobic side of the amphipathic peptides may immerse into membrane without deep penetration. Based on these results, we postulate that the formation of the basic amphipathic beta-structure on acidic lipid bilayers may be due to the combined effect of electrostatic and hydrophobic interactions between basic peptides and acidic lipid bilayers.

To investigate the relationships between enzyme inactivation and conformational change, the effects of heat and guanidine hydrochloride (GnHC1) on the STA1 gene glucoamylase (STA1GA) of Saccharomyces cerevisiae var. diastaticus were examined by circular dichroism and fluorescence spectroscopies. A conformational change was observed in the thermal denaturation of STA1GA, while extensive enzyme inactivation occurred in GnHC1 denaturation before noticeable conformational change.

Diphenyl 1-amino-2-phenylethylphosphonate was introduced to poly(ethylene glycol)s (PEGs) with average molecular masses of 300, 400, and 600 to prepare water-insoluble PEG-inhibitor conjugates. Interestingly, only the conjugate from PEG with an average molecular weight of 600 formed a precipitate with chymotrypsin but not with trypsin. The results demonstrated that the PEG-inhibitor conjugate is useful for separation of chymotrypsin.

Benzil (1) was selectively reduced to (S)-benzoin (2) in the presence of a wild-type Bacillus cereus Tim-r01. A 92% yield of 2 with 94% enantiomeric excess ratio was attained in phosphate-buffered saline (PBS) (pH 7.5) by using glucose as a nutrient at 37 degrees C for 12 h. Compound 2 was not reduced further to hydrobenzoin (3) at all. The reduction activity differed greatly depending on the strain of B. cereus. Under these conditions the B. cereus strains IFO3001, IFO15305, IAM1110, IAM1229, IAM1656, and IAM1729 gave 2 in yields ranging from 23 to 46% and the configuration of 2 was (S)-form (7 to 86% ee).

Artificial peptides designed to form alpha-helical, beta-turn, antiparallel beta-sheet and beta-hairpin structures which are among the motifs most frequently found in natural DNA/RNA binding proteins were synthesized and their characteristic features were examined in the presence or absence of double or triple stranded DNA by means of UV melting experiments, CD spectra, SPR measurements. It was revealed that amphiphilic character arising from the specific secondary structures and positive charge in the hydrophobic face of peptides played an important role in the interaction with DNA, and that hybrid duplex and triplex were intensively stabilized by the cationic amphiphilic peptides. It was also found that these peptides could protect dsDNA against DNase 1 digestion. These results indicate that structurally designed amphiphilic peptides synthesized in the present study can be powerful tools for antisense and antigene strategies.

The suppressive effects of noncyclic cyanamides (guanidine hydrochloride, urea, and thiourea) on the retrogradation of waxy corn starch (WCS) gel were examined using differential scanning calorimetry and X-ray powder diffraction. We demonstrated that thiourea, guanidine hydrochloride, and urea effectively suppressed the retrogradation of the WCS gel in this order.

In order to investigate the conformation and orientation of lipid-bound peptides and proteins in the lipid bilayer, basic amphipathic alpha-helical peptides with a long alkyl chain, palmitoyl-(Leu-Ala-Arg-Leu)3-NHCH3 (P-4(3)) and Ac-Leu-Ala-Arg-Leu-Trp-Amy-Arg-Leu-Leu-Ala-Arg-Leu-NHCH3 (Amy-4(3), Amy; alpha-aminomyristic acid) were designed and synthesized. The conformational features and spectroscopic behavior in a buffer solution and in neutral and acidic liposomes were studied by CD, dye-leakage, and fluorescence measurements. The CD data indicated that P-4(3) took an alpha-helical structure in aqueous solution and in neutral and acidic liposomes. On the other hand, Amy-4(3) took a beta-structure in aqueous solution and an alpha-helical structure in neutral and acidic liposomes. The conformational change of Amy-4(3) was confirmed by fluorescence study on lipid titration of the peptide. The dye-leakage experiment showed that both peptides interacted with acidic liposomes to perturb them, but less effectively than Ac-(Leu-Ala-Arg-Leu)3-NHCH3 (4(3)) which has no long alkyl group. Based on these results, a discussion is made concerning the conformation and orientation of peptides in aqueous solution and in the lipid bilayer.

Formation of by-products of pyrenylalanine-peptides was observed during the cleavage of a tosyl group in pyrenylalanine-peptides containing an Arg(Tos) residue with HF. NMR and fluorescence experiments showed that by-products were compounds in which a pyrenyl group was modified with a tosyl group(s). The side reaction was little suppressed by the addition of usual scavengers such as anisole, 1,2-ethanedithiol, thioanisole and p-cresol. Under the conditions used for the cleavage of N alpha-Boc group, i.e., trifluoroacetic acid or 4 M HCl in dioxane, the pyrenylalanine residue was stable. No side reaction was, furthermore, observed in the reductive cleavage with sodium in liquid ammonia. These results suggest that the side reaction may be due to an electrophilic attack of tosyl cations to the electron-rich pyrenyl group in the pyrenylalanine residue under the HF-mediated acidic conditions.