[Objective] This study was to understand the effects of β-Amino butyric acid(abbreviated as BABA) induced rice blast resistance on reactive oxygen metabolism. [Method] Using the cultivar Chaochan 2 that is highly sus...[Objective] This study was to understand the effects of β-Amino butyric acid(abbreviated as BABA) induced rice blast resistance on reactive oxygen metabolism. [Method] Using the cultivar Chaochan 2 that is highly susceptible to disease as experimental material, the changes of catalase(CAT), and superoxide dismutase(SOD) and MDA activities in rice treated by BABA were investigated. [Result] In rice plants treated by BABA, the activities of CAT and SOD increased, meanwhile the MDA content also rose to some extent, resulting in the disease resistance to rice blast. [Conclusion] By influencing reactive oxygen metabolism, BABA endows rice plants with resistance to rice blast. BABA is safe to environment and has highly resistance-inducing capacity, it could be generalized in production.展开更多
Frankincense can promote blood circulation. Acetyl-11-keto-β-boswellic acid (AKBA) is a small molecule with anti-inflammatory properties that is derived from Boswellia serrata. Here, we hypothesized that it may pro...Frankincense can promote blood circulation. Acetyl-11-keto-β-boswellic acid (AKBA) is a small molecule with anti-inflammatory properties that is derived from Boswellia serrata. Here, we hypothesized that it may promote regeneration of injured sciatic nerve. To address this hypothesis, we established a rat model of sciatic nerve injury using a nerve clamping method. Rats were administered AKBA once every 2 days at doses of 1.5, 3, and 6 mg/kg by intraperitoneal injection for 30 days from the 1st day after injury. Sciatic nerve function was evaluated using the sciatic functional index. Degree of muscle atrophy was measured using the triceps surae muscle Cuadros index.Neuropathological changes were observed by hematoxylin-eosin staining. Western blot analysis was used to detect expression of phospho-extracellular signal-regulated kinase 1 and 2 (p-ERK1/2) in injured nerve. S100 immunoreactivity in injured nerve was detected by immunohistochemistry. In vivo experiments showed that 3 and 6 mg/kg AKBA significantly increased sciatic nerve index, Cuadros index of triceps muscle, p-ERK1/2 expression, and S100 immunoreactivity in injured sciatic nerve of sciatic nerve injury model rats. Furthermore,for in vitro experiments, Schwann cells were treated with AKBA at 0–20 μg/mL. Proliferation of Schwann cells was detected by Cell Counting Kit-8 colorimetry assay. The results showed that 2 μg/mL AKBA is the optimal therapeutic concentration. In addition, ERK phosphorylation levels increased following 2 μg/mL AKBA treatment. In the presence of the ERK1/2 inhibitor, PD98059 (2.5 μL/mL), the AKBA-induced increase in p-ERK1/2 protein expression was partially abrogated. In conclusion, our study shows that AKBA promotes peripheral nerve regeneration with ERK protein phosphorylation playing a key role in this process.展开更多
Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the ...Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the results indicate that Pr(Ⅲ) interacts with MP11, increasing the non planarity of porphyrin periphery, leading MP11 to form two conformations when titrated by Pr(Ⅲ). Excessive Pr(Ⅲ) acts as a contaminant in living organism. H + and Pr(Ⅲ) have antagonistic effect on MP11, suggesting that at suitable concentration under physiological conditions, Pr(Ⅲ) can be used as biomodulator in protecting plants from acid rain stress or in rehabilitating the harm.展开更多
BACKGROUND Gastric cancer is one of the most common malignant tumors of the digestive system worldwide,posing a serious danger to human health.Cyclooxygenase(COX)-2 plays an important role in the carcinogenesis and pr...BACKGROUND Gastric cancer is one of the most common malignant tumors of the digestive system worldwide,posing a serious danger to human health.Cyclooxygenase(COX)-2 plays an important role in the carcinogenesis and progression of gastric cancer.Acetyl-11-keto-β-boswellic acid(AKBA)is a promising drug for cancer therapy,but its effects and mechanism of action on human gastric cancer remain unclear.AIM To evaluate whether the phosphatase and tensin homolog(PTEN)/Akt/COX-2 signaling pathway is involved in the anti-tumor effect of AKBA in gastric cancer.METHODS Human poorly differentiated BGC823 and moderately differentiated SGC7901 gastric cancer cells were routinely cultured in Roswell Park Memorial Institute 1640 medium supplemented with 10%fetal bovine serum and 1%penicillin/streptomycin.Gastric cancer cell proliferation was determined by methyl thiazolyl tetrazolium colorimetric assay.Apoptosis was measured by flow cytometry.Cell migration was assessed using the wound-healing assay.Expression of Bcl-2,Bax,proliferating cell nuclear antigen,PTEN,p-Akt,and COX-2 were detected by Western blot analysis.A xenograft nude mouse model of human gastric cancer was established to evaluate the anti-cancer effect of AKBA RESULTS AKBA significantly inhibited the proliferation of gastric cancer cells in a dose-and time-dependent manner,inhibited migration in a time-dependent manner,and induced apoptosis in a dose-dependent manner in vitro;it also inhibited tumor growth in vivo.AKBA up-regulated the expression of PTEN and Bax,and downregulated the expression of proliferating cell nuclear antigen,Bcl-2,p-Akt,and COX-2 in a dose-dependent manner.The PTEN inhibitor bpv(Hopic)reversed the high expression of PTEN and low expression of p-Akt and COX-2 that were induced by AKBA.The Akt inhibitor MK2206 combined with AKBA downregulated the expression of p-Akt and COX-2,and the combined effect was better than that of AKBA alone.CONCLUSION AKBA inhibits the proliferation and migration and promotes the apoptosis of gastric cancer cells through the PTEN/Akt/COX-2 signaling pathway.展开更多
Three new dimethyltin complexes of N-(3-methoxysalicylidene)-α-amino acid,(CH3)2Sn(3-CH3O-2-OC6H3CH=NCHRCOO)(R = H,1;CH3,2;(CH3)2CH,3),have been synthe-sized by treating dimethyltin dichloride with the pota...Three new dimethyltin complexes of N-(3-methoxysalicylidene)-α-amino acid,(CH3)2Sn(3-CH3O-2-OC6H3CH=NCHRCOO)(R = H,1;CH3,2;(CH3)2CH,3),have been synthe-sized by treating dimethyltin dichloride with the potassium salt of the ligand and characterized by elemental analysis,IR and 1H NMR spectra.The crystal structure of [(CH3)2Sn(3-CH3O-2-OC6H3CH=NCH2COO)(CH3OH)]2 H2O(1a),formed from methanol solution of 1,has been deter-mined.The crystal belongs to the monoclinic system,space group C/2c with a = 20.636(3),b = 7.8854(9),c = 20.668(2) ,β= 113.265(2)°,V = 3089.7(6) 3,Z = 4,Dc = 1.707 g/cm3,= 1.675 mm-1,F(000) = 1592,R = 0.0301 and wR = 0.0841.In complex 1a,the tin atom is six-coordinate and possesses a distorted [SnC2NO3] octahedral geometry with the two methyl groups occupying the trans positions.The weak Sn O interactions and intermolecular hydrogen bonds connected the molecules into an infinite chain.展开更多
Sitagliptin is the first new anti-diabetic drug in DPP-Ⅳ inhibitor class. The general synthesis of sitagliptin is by coupling of the β-amino acid fragment with the heterocycle fragment. Though the specific β-amino ...Sitagliptin is the first new anti-diabetic drug in DPP-Ⅳ inhibitor class. The general synthesis of sitagliptin is by coupling of the β-amino acid fragment with the heterocycle fragment. Though the specific β-amino acid can be easily made from the corresponding R-amino acid by Arndt-Eistert hornologation, the optically pure precursor R-amino acid is difficult to prepare. We herein reported a practical protocol to make the trifluorophenyl substituted R-amino acid 4 in 〉99.9% ee and 40.3% yield by the enzymatic resolution employing enantioselective hydrolysis and a general separation procedure. This protocol requires only cheap starting materials and friendly reaction condition. The procedure not only allows people to prepare the drug substance, but also provides an alternative method for prepareing the rare α-amino acid and the subsequent β-amino acid.展开更多
Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell ...Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1).展开更多
Objective: With regard to the 2010 edition of Dietary Reference Intakes for Japanese (DRIs-2010), we investigated whether the DRIs for two age groups, breast-fed infants aged 6-8 and 9-11 months, can be fulfilled for ...Objective: With regard to the 2010 edition of Dietary Reference Intakes for Japanese (DRIs-2010), we investigated whether the DRIs for two age groups, breast-fed infants aged 6-8 and 9-11 months, can be fulfilled for every nutrient in actual dietary practice. Design: We evaluated (1) whether the DRIs for all nutrients can be fulfilled in a formula with energy and protein exceeding their DRIs, (2) whether the DRIs for all nutrients can be fulfilled in a formula prepared in accordance with Japanese government-recommended weaning guidelines, and (3) what kinds of formulas can be prepared if the DRIs for all nutrients are fulfilled without referring to the weaning guidelines. Setting: Simulation of diet menu on the basis of published data in our university and survey of diet menu in a university hospital attached to a national medical school. Subjects: The three types of formulas were planned for ten days. Results: It was impossible to simultaneously fulfil the DRIs for 6 - 8-month-old infants concerning pantothenic acid, vitamin D, and iron and those for 9 - 11-month-old infants concerning these nutrients plus protein. Conclusion: According to the DRIs-2010, the DRI for all nutrients could not be fulfilled in an ingestible formula.展开更多
tert-Butyl (R)-3-amino-3-(3-fluorophenyl)propanoate(5) was prepared with conventional debenzylation method. However, the tert-butyl (R)-3-[(S)-1-phenylethyl-amino]-3-(3-fluorophenyl) propanoate(6) and te...tert-Butyl (R)-3-amino-3-(3-fluorophenyl)propanoate(5) was prepared with conventional debenzylation method. However, the tert-butyl (R)-3-[(S)-1-phenylethyl-amino]-3-(3-fluorophenyl) propanoate(6) and tert-butyl (R)-3-amino-3-phenylpropanoate(7) were generated as the byproducts under the general catalytic hydrogenation Pd(OH)2/C-H2 conditions. So a series of experiments was performed to optimize the reaction conditions so that product 5 could be obtained with high purity and yield. Finally an effective catalytic system, Pd/C-HCOOH-CH3OH, was discovered.展开更多
A novel organophosphorus compound containing the structure of bothβ-amino acid andβ-aminophosphonate is designed and synthesized.Arbuzov reaction with P(OEt)_3,the N-Boc protected iodide 3 cannot provide the desir...A novel organophosphorus compound containing the structure of bothβ-amino acid andβ-aminophosphonate is designed and synthesized.Arbuzov reaction with P(OEt)_3,the N-Boc protected iodide 3 cannot provide the desired product but 2-oxazolidinone 4 because of the neighboring-group participation of the Boc moiety.To avoid the intramolecular participation of the carbamates,the Ts protecting group is employed and the Ts-protected iodide 5 affords the target product successfully.展开更多
The title complexes, R′2Sn(3,5-Br2-2-OC6H2CH=NCHRCOO), and their diphenyltindichloride adduct, R′2Sn(3,5-Br2-2-OC6H2CH=NCHRCOO)?SnPh2Cl2, were synthesized and char-acterized by elemental analysis, IR, H and C NMR an...The title complexes, R′2Sn(3,5-Br2-2-OC6H2CH=NCHRCOO), and their diphenyltindichloride adduct, R′2Sn(3,5-Br2-2-OC6H2CH=NCHRCOO)?SnPh2Cl2, were synthesized and char-acterized by elemental analysis, IR, H and C NMR and X-ray single crystal diffraction. The 1 13structural features of the compounds were described.展开更多
Dietary γ-amino butyric acid (GABA) has been suggested to decrease systolic blood pressure. This study aimed to ex-amine the effects of dietary GABA on the life span of stroke-prone spontaneously hypertensive rats (S...Dietary γ-amino butyric acid (GABA) has been suggested to decrease systolic blood pressure. This study aimed to ex-amine the effects of dietary GABA on the life span of stroke-prone spontaneously hypertensive rats (SHRSPs). In this study, life span was determined for SHRSPs provided 1% NaCl solution or 0.01% GABA in 1% NaCl solution as drinking water. The life span of the GABA-fed group (76.3 ± 1.65 days) was significantly shorter than that of the control group (81.6 ± 0.88 days). The results of this study may not be applicable to humans. Future studies will be necessary to elucidate the mechanism underlying this phenomenon.展开更多
The conformations of four β-amino acids in a model peptide environment were investigated using Hartree-Fock (HF) and density functional theory (DFT) methods in gas phase and with solvation. Initial structures were ob...The conformations of four β-amino acids in a model peptide environment were investigated using Hartree-Fock (HF) and density functional theory (DFT) methods in gas phase and with solvation. Initial structures were obtained by varying dihedral angles in increments of 45° in the range 0° - 360°. Stable geometries were optimized at both levels of theory with the correlation consistent double-zeta basis set with polarization functions (cc-pVDZ). The results suggest that solvation generally stabilizes the conformations relative to the gas phase and that intramolecular hydrogen bonding may play an important role in the stability of the conformations. The β3 structures, in which the R-group of the amino acid is located on the carbon atom next to the N-terminus, are somewhat more stable relative to each other than the β2 structures which have the R-group on the carbon next to the carbonyl.展开更多
Racemic O-methyl O-pheayl thiophosphoric acid 1 has been successfully resolved through its quinine and brucine salts in methanol solution by fractional crystallization. The absolute configurations of the optically act...Racemic O-methyl O-pheayl thiophosphoric acid 1 has been successfully resolved through its quinine and brucine salts in methanol solution by fractional crystallization. The absolute configurations of the optically active 1 have been established as (+)-R-1 and (-)-S-1 by chemical correlation.展开更多
Peroxyoxalate chemiluminescence was, for the first time, examined by using ternary mixed solutions of water-hydrophilic/hydrophobic organic solvent. Eosin Y as a model fluorescence compound was dissolved with the tern...Peroxyoxalate chemiluminescence was, for the first time, examined by using ternary mixed solutions of water-hydrophilic/hydrophobic organic solvent. Eosin Y as a model fluorescence compound was dissolved with the ternary solutions of water (1.0 mM carbonate buffer, pH 9.0)-acetonitrile-ethyl acetate, water-rich of 15:3:2 volume ratio and organic solvent-rich of 3:8:4 volume ratio, to which bis(2,4,6-trichlorophenyl) oxalate and hydrogen peroxide chemiluminescence reagent were added. The chemiluminescence observed with the ternary solutions, especially the organic solvent-rich solution, showed a larger signal than that observed with the water only solution or water-acetonitrile mixed solution. Chemiluminescence in the presence of twenty types of α-amino acid was similarly examined by using the ternary organic solvent-rich solution. The chemiluminescence of three α-amino acids with fluorescence properties was enhanced with the ternary solution. The data reported here may contribute to development of a new, sensitive peroxyoxalate chemiluminescence detection system.展开更多
Novel fluorine substituted α-amino phosphonic acids containing 1,2,4-triazin- 5-one (6a-f) have been obtained from fluoroacylation of 6-(2′-amino-5′-nitrophenyl)-3-thioxo-1,2,4-triazin-5(4H)-one (...Novel fluorine substituted α-amino phosphonic acids containing 1,2,4-triazin- 5-one (6a-f) have been obtained from fluoroacylation of 6-(2′-amino-5′-nitrophenyl)-3-thioxo-1,2,4-triazin-5(4H)-one (1) followed by ammonilysis to give the corresponding 3-amino-derivative 3. Condensation of compound 3 with nitro/halogenated aromatic aldehydes yielded the Schiff bases 4. The simple addition of diethyl phosphonate to compound 4 produced the α-amino phosphonates 5. Acidic hydrolysis of compound 5 produced the fluorine substituted α-amino acids derivatives 6. Structures of the new compounds have been established with the help of elemental analysis and spectral measurements. Also, the products evaluated as antioxidants, where the fluorinated α-amino phosphonic acids 6 are more active than the other synthesized systems.展开更多
The main eicosanoids inflammatory mediators, prostaglandins and leukotrienes, are both generated from arachidonic acid (AA;20:4 n-6). AA is a member of polyunsaturated fatty acids (PUFAs). Numerous studies have demons...The main eicosanoids inflammatory mediators, prostaglandins and leukotrienes, are both generated from arachidonic acid (AA;20:4 n-6). AA is a member of polyunsaturated fatty acids (PUFAs). Numerous studies have demonstrated that various contents of PUFAs can modulate the inflammatory responses. However, fewer studies have examined n-9PUFAs and their effects on the inflammatory responses. In the present study, the role of 5,8,11-cis-eicosatrienoic acid (ETrA;20:3 n-9, also called Mead acid) in the inflammatory responses has been investigated. The anti-inflammatory activities of ETrA were examined using an in vitro macrophage system and the inhibitory effect was confirmed by western blot analysis for iNOS and COX-2 expressions. The interactions between ETrA and COX-2 protein were simulated to produce a computer modeling protein-ligand complexes and the results suggest a possible mechanism for the effects of ETrA. In this study, we described a significant inhibition of the inflammatory activities initiated by ETrA. Since ETrA is a substance presented in the tissues of young animals, we therefore anticipate that ETrA can be utilized as a natural therapeutic supplement to inhibit inflammatory activities.展开更多
基金Supported by National Key Technology R&D Program During the Eleventh Five Year Plan (2006BAD08A04)Innovation Project(20076020)~~
文摘[Objective] This study was to understand the effects of β-Amino butyric acid(abbreviated as BABA) induced rice blast resistance on reactive oxygen metabolism. [Method] Using the cultivar Chaochan 2 that is highly susceptible to disease as experimental material, the changes of catalase(CAT), and superoxide dismutase(SOD) and MDA activities in rice treated by BABA were investigated. [Result] In rice plants treated by BABA, the activities of CAT and SOD increased, meanwhile the MDA content also rose to some extent, resulting in the disease resistance to rice blast. [Conclusion] By influencing reactive oxygen metabolism, BABA endows rice plants with resistance to rice blast. BABA is safe to environment and has highly resistance-inducing capacity, it could be generalized in production.
文摘Frankincense can promote blood circulation. Acetyl-11-keto-β-boswellic acid (AKBA) is a small molecule with anti-inflammatory properties that is derived from Boswellia serrata. Here, we hypothesized that it may promote regeneration of injured sciatic nerve. To address this hypothesis, we established a rat model of sciatic nerve injury using a nerve clamping method. Rats were administered AKBA once every 2 days at doses of 1.5, 3, and 6 mg/kg by intraperitoneal injection for 30 days from the 1st day after injury. Sciatic nerve function was evaluated using the sciatic functional index. Degree of muscle atrophy was measured using the triceps surae muscle Cuadros index.Neuropathological changes were observed by hematoxylin-eosin staining. Western blot analysis was used to detect expression of phospho-extracellular signal-regulated kinase 1 and 2 (p-ERK1/2) in injured nerve. S100 immunoreactivity in injured nerve was detected by immunohistochemistry. In vivo experiments showed that 3 and 6 mg/kg AKBA significantly increased sciatic nerve index, Cuadros index of triceps muscle, p-ERK1/2 expression, and S100 immunoreactivity in injured sciatic nerve of sciatic nerve injury model rats. Furthermore,for in vitro experiments, Schwann cells were treated with AKBA at 0–20 μg/mL. Proliferation of Schwann cells was detected by Cell Counting Kit-8 colorimetry assay. The results showed that 2 μg/mL AKBA is the optimal therapeutic concentration. In addition, ERK phosphorylation levels increased following 2 μg/mL AKBA treatment. In the presence of the ERK1/2 inhibitor, PD98059 (2.5 μL/mL), the AKBA-induced increase in p-ERK1/2 protein expression was partially abrogated. In conclusion, our study shows that AKBA promotes peripheral nerve regeneration with ERK protein phosphorylation playing a key role in this process.
文摘Interaction between rare earth ion praseodymium (Pr(Ⅲ)) and MP11 with/without hydrogen ion (H +) in different media( aqueous, phosphate buffer, physiological condition) were studied by UV Vis spectroscopy. All the results indicate that Pr(Ⅲ) interacts with MP11, increasing the non planarity of porphyrin periphery, leading MP11 to form two conformations when titrated by Pr(Ⅲ). Excessive Pr(Ⅲ) acts as a contaminant in living organism. H + and Pr(Ⅲ) have antagonistic effect on MP11, suggesting that at suitable concentration under physiological conditions, Pr(Ⅲ) can be used as biomodulator in protecting plants from acid rain stress or in rehabilitating the harm.
基金Supported by the Natural Science Foundation of Jiangsu,No.BK20171508。
文摘BACKGROUND Gastric cancer is one of the most common malignant tumors of the digestive system worldwide,posing a serious danger to human health.Cyclooxygenase(COX)-2 plays an important role in the carcinogenesis and progression of gastric cancer.Acetyl-11-keto-β-boswellic acid(AKBA)is a promising drug for cancer therapy,but its effects and mechanism of action on human gastric cancer remain unclear.AIM To evaluate whether the phosphatase and tensin homolog(PTEN)/Akt/COX-2 signaling pathway is involved in the anti-tumor effect of AKBA in gastric cancer.METHODS Human poorly differentiated BGC823 and moderately differentiated SGC7901 gastric cancer cells were routinely cultured in Roswell Park Memorial Institute 1640 medium supplemented with 10%fetal bovine serum and 1%penicillin/streptomycin.Gastric cancer cell proliferation was determined by methyl thiazolyl tetrazolium colorimetric assay.Apoptosis was measured by flow cytometry.Cell migration was assessed using the wound-healing assay.Expression of Bcl-2,Bax,proliferating cell nuclear antigen,PTEN,p-Akt,and COX-2 were detected by Western blot analysis.A xenograft nude mouse model of human gastric cancer was established to evaluate the anti-cancer effect of AKBA RESULTS AKBA significantly inhibited the proliferation of gastric cancer cells in a dose-and time-dependent manner,inhibited migration in a time-dependent manner,and induced apoptosis in a dose-dependent manner in vitro;it also inhibited tumor growth in vivo.AKBA up-regulated the expression of PTEN and Bax,and downregulated the expression of proliferating cell nuclear antigen,Bcl-2,p-Akt,and COX-2 in a dose-dependent manner.The PTEN inhibitor bpv(Hopic)reversed the high expression of PTEN and low expression of p-Akt and COX-2 that were induced by AKBA.The Akt inhibitor MK2206 combined with AKBA downregulated the expression of p-Akt and COX-2,and the combined effect was better than that of AKBA alone.CONCLUSION AKBA inhibits the proliferation and migration and promotes the apoptosis of gastric cancer cells through the PTEN/Akt/COX-2 signaling pathway.
基金supported by the Natural Science Foundation of Shandong Province (ZR2010BL012)thescientific research projects of Binzhou University (BZXYG0901,BZXYQNLG200912,BZXYFB20100403)
文摘Three new dimethyltin complexes of N-(3-methoxysalicylidene)-α-amino acid,(CH3)2Sn(3-CH3O-2-OC6H3CH=NCHRCOO)(R = H,1;CH3,2;(CH3)2CH,3),have been synthe-sized by treating dimethyltin dichloride with the potassium salt of the ligand and characterized by elemental analysis,IR and 1H NMR spectra.The crystal structure of [(CH3)2Sn(3-CH3O-2-OC6H3CH=NCH2COO)(CH3OH)]2 H2O(1a),formed from methanol solution of 1,has been deter-mined.The crystal belongs to the monoclinic system,space group C/2c with a = 20.636(3),b = 7.8854(9),c = 20.668(2) ,β= 113.265(2)°,V = 3089.7(6) 3,Z = 4,Dc = 1.707 g/cm3,= 1.675 mm-1,F(000) = 1592,R = 0.0301 and wR = 0.0841.In complex 1a,the tin atom is six-coordinate and possesses a distorted [SnC2NO3] octahedral geometry with the two methyl groups occupying the trans positions.The weak Sn O interactions and intermolecular hydrogen bonds connected the molecules into an infinite chain.
基金supported in part by grant from Science and Technology Program of Guangdong Province(No. 2007B031503005).
文摘Sitagliptin is the first new anti-diabetic drug in DPP-Ⅳ inhibitor class. The general synthesis of sitagliptin is by coupling of the β-amino acid fragment with the heterocycle fragment. Though the specific β-amino acid can be easily made from the corresponding R-amino acid by Arndt-Eistert hornologation, the optically pure precursor R-amino acid is difficult to prepare. We herein reported a practical protocol to make the trifluorophenyl substituted R-amino acid 4 in 〉99.9% ee and 40.3% yield by the enzymatic resolution employing enantioselective hydrolysis and a general separation procedure. This protocol requires only cheap starting materials and friendly reaction condition. The procedure not only allows people to prepare the drug substance, but also provides an alternative method for prepareing the rare α-amino acid and the subsequent β-amino acid.
基金This work was supported by the National Natural Science Foundation of China(No.39870661). Phone: (0086-451)-3641309 Fax: (0086-451)-3641253
文摘Objective: To determine the effect of cis-9, trans-1 1-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and the possible mechanism of the inhibitory effect of c9,t11-CLA. Methods: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B1, D1, p16ink4a and p21cip/waf1 of MCF-7 cells at various c9,t11-CLA concentrations (25μM, 50μM, 100μM and 200μM), at 24h and 48h. 96% ethand was used as negative control. Results: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9,t11-CLA. After treatment with various doses of c9,t11-CLA mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively. Inhibitory effect of c9,t11-CLA on DNA synthesis (except for 25μM, 24h) was demonstrated by significantly less incorporation of 3H-TdR than the negative control (P<0.05 and P<0.01). To further investigate the influence of the cell cycle progression, we found that c9,t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that incubation with different concentration of c9,t11-CLA at various times significantly decreased the expression of PCNA, Cyclin A, B1, D1 in MCF-7 cells compared to the negative control (P<0.01), whereas the expression of p16ink4a and p21cip/waf1, cyclin-dependent kinases inhibitors (CDKI), were increased. Conclusions: The cell growth and proliferation of MCF-7 cells is inhibited by c9,t11-CLA via blocking cell cycle, accompanying reduced expression of cyclin A, B1, D1 and enhanced expression of CDKI (p16ink4a and p21cip/waf1).
文摘Objective: With regard to the 2010 edition of Dietary Reference Intakes for Japanese (DRIs-2010), we investigated whether the DRIs for two age groups, breast-fed infants aged 6-8 and 9-11 months, can be fulfilled for every nutrient in actual dietary practice. Design: We evaluated (1) whether the DRIs for all nutrients can be fulfilled in a formula with energy and protein exceeding their DRIs, (2) whether the DRIs for all nutrients can be fulfilled in a formula prepared in accordance with Japanese government-recommended weaning guidelines, and (3) what kinds of formulas can be prepared if the DRIs for all nutrients are fulfilled without referring to the weaning guidelines. Setting: Simulation of diet menu on the basis of published data in our university and survey of diet menu in a university hospital attached to a national medical school. Subjects: The three types of formulas were planned for ten days. Results: It was impossible to simultaneously fulfil the DRIs for 6 - 8-month-old infants concerning pantothenic acid, vitamin D, and iron and those for 9 - 11-month-old infants concerning these nutrients plus protein. Conclusion: According to the DRIs-2010, the DRI for all nutrients could not be fulfilled in an ingestible formula.
基金Supported by the National Key New Drug Creation Program of China(No.2009ZX09103-001)the Jiangsu Key Laboratory of Molecular Targeted Antitumor Drug Research Foundation China(No.BM2008201)
文摘tert-Butyl (R)-3-amino-3-(3-fluorophenyl)propanoate(5) was prepared with conventional debenzylation method. However, the tert-butyl (R)-3-[(S)-1-phenylethyl-amino]-3-(3-fluorophenyl) propanoate(6) and tert-butyl (R)-3-amino-3-phenylpropanoate(7) were generated as the byproducts under the general catalytic hydrogenation Pd(OH)2/C-H2 conditions. So a series of experiments was performed to optimize the reaction conditions so that product 5 could be obtained with high purity and yield. Finally an effective catalytic system, Pd/C-HCOOH-CH3OH, was discovered.
文摘A novel organophosphorus compound containing the structure of bothβ-amino acid andβ-aminophosphonate is designed and synthesized.Arbuzov reaction with P(OEt)_3,the N-Boc protected iodide 3 cannot provide the desired product but 2-oxazolidinone 4 because of the neighboring-group participation of the Boc moiety.To avoid the intramolecular participation of the carbamates,the Ts protecting group is employed and the Ts-protected iodide 5 affords the target product successfully.
基金This work was supported by the National Natural Science Foundation of China(No.20173050).
文摘The title complexes, R′2Sn(3,5-Br2-2-OC6H2CH=NCHRCOO), and their diphenyltindichloride adduct, R′2Sn(3,5-Br2-2-OC6H2CH=NCHRCOO)?SnPh2Cl2, were synthesized and char-acterized by elemental analysis, IR, H and C NMR and X-ray single crystal diffraction. The 1 13structural features of the compounds were described.
文摘Dietary γ-amino butyric acid (GABA) has been suggested to decrease systolic blood pressure. This study aimed to ex-amine the effects of dietary GABA on the life span of stroke-prone spontaneously hypertensive rats (SHRSPs). In this study, life span was determined for SHRSPs provided 1% NaCl solution or 0.01% GABA in 1% NaCl solution as drinking water. The life span of the GABA-fed group (76.3 ± 1.65 days) was significantly shorter than that of the control group (81.6 ± 0.88 days). The results of this study may not be applicable to humans. Future studies will be necessary to elucidate the mechanism underlying this phenomenon.
文摘The conformations of four β-amino acids in a model peptide environment were investigated using Hartree-Fock (HF) and density functional theory (DFT) methods in gas phase and with solvation. Initial structures were obtained by varying dihedral angles in increments of 45° in the range 0° - 360°. Stable geometries were optimized at both levels of theory with the correlation consistent double-zeta basis set with polarization functions (cc-pVDZ). The results suggest that solvation generally stabilizes the conformations relative to the gas phase and that intramolecular hydrogen bonding may play an important role in the stability of the conformations. The β3 structures, in which the R-group of the amino acid is located on the carbon atom next to the N-terminus, are somewhat more stable relative to each other than the β2 structures which have the R-group on the carbon next to the carbonyl.
基金This project was supported by National Natural Science Foundation of China
文摘Racemic O-methyl O-pheayl thiophosphoric acid 1 has been successfully resolved through its quinine and brucine salts in methanol solution by fractional crystallization. The absolute configurations of the optically active 1 have been established as (+)-R-1 and (-)-S-1 by chemical correlation.
文摘Peroxyoxalate chemiluminescence was, for the first time, examined by using ternary mixed solutions of water-hydrophilic/hydrophobic organic solvent. Eosin Y as a model fluorescence compound was dissolved with the ternary solutions of water (1.0 mM carbonate buffer, pH 9.0)-acetonitrile-ethyl acetate, water-rich of 15:3:2 volume ratio and organic solvent-rich of 3:8:4 volume ratio, to which bis(2,4,6-trichlorophenyl) oxalate and hydrogen peroxide chemiluminescence reagent were added. The chemiluminescence observed with the ternary solutions, especially the organic solvent-rich solution, showed a larger signal than that observed with the water only solution or water-acetonitrile mixed solution. Chemiluminescence in the presence of twenty types of α-amino acid was similarly examined by using the ternary organic solvent-rich solution. The chemiluminescence of three α-amino acids with fluorescence properties was enhanced with the ternary solution. The data reported here may contribute to development of a new, sensitive peroxyoxalate chemiluminescence detection system.
文摘Novel fluorine substituted α-amino phosphonic acids containing 1,2,4-triazin- 5-one (6a-f) have been obtained from fluoroacylation of 6-(2′-amino-5′-nitrophenyl)-3-thioxo-1,2,4-triazin-5(4H)-one (1) followed by ammonilysis to give the corresponding 3-amino-derivative 3. Condensation of compound 3 with nitro/halogenated aromatic aldehydes yielded the Schiff bases 4. The simple addition of diethyl phosphonate to compound 4 produced the α-amino phosphonates 5. Acidic hydrolysis of compound 5 produced the fluorine substituted α-amino acids derivatives 6. Structures of the new compounds have been established with the help of elemental analysis and spectral measurements. Also, the products evaluated as antioxidants, where the fluorinated α-amino phosphonic acids 6 are more active than the other synthesized systems.
文摘The main eicosanoids inflammatory mediators, prostaglandins and leukotrienes, are both generated from arachidonic acid (AA;20:4 n-6). AA is a member of polyunsaturated fatty acids (PUFAs). Numerous studies have demonstrated that various contents of PUFAs can modulate the inflammatory responses. However, fewer studies have examined n-9PUFAs and their effects on the inflammatory responses. In the present study, the role of 5,8,11-cis-eicosatrienoic acid (ETrA;20:3 n-9, also called Mead acid) in the inflammatory responses has been investigated. The anti-inflammatory activities of ETrA were examined using an in vitro macrophage system and the inhibitory effect was confirmed by western blot analysis for iNOS and COX-2 expressions. The interactions between ETrA and COX-2 protein were simulated to produce a computer modeling protein-ligand complexes and the results suggest a possible mechanism for the effects of ETrA. In this study, we described a significant inhibition of the inflammatory activities initiated by ETrA. Since ETrA is a substance presented in the tissues of young animals, we therefore anticipate that ETrA can be utilized as a natural therapeutic supplement to inhibit inflammatory activities.