2009 Volume 20 Issue 5

Design,synthesis and anti-HBV activity of novel bis(trifluoroethyl)phosphonomethyl ether derivatives of acyclovir
Peng Lu , Sai Hong Jiang , Jiang Xia Liu , Yu She Yang , Ru Yun Ji
2009, 20(5): 507-510  doi: 10.1016/j.cclet.2008.12.057
[Abstract](175) [FullText HTML] [PDF 253KB](0)
A series of novel bis(trifluoroethyl) phosphonomethyl ether derivatives of acyclovir was synthesized and their in vitro anti-HBV activity was evaluated in HepG2 2.2.15 cells. In contrast to acyclovir, most of the described phosphonates emerged as potent inhibitors of HBV replication. Especially, the most active compound 11 with IC50 value of 2.92 mmol/L was 33 times more potent than acyclovir with IC50 value of 100 mmol/L.
FeCl3 catalyzed diarylmethanes formations
Zhong Xian Li , Zheng Duan , Yang Jie Wu
2009, 20(5): 511-513  doi: 10.1016/j.cclet.2009.01.033
[Abstract](188) [FullText HTML] [PDF 243KB](0)
Under mild condition, using FeCl3 as catalyst, a series of functionalized diarylmethanes were prepared efficiently from the reactions of arenes with paraformaldehyde. This catalytic system is not sensitive to air and moisture.
KBrO3/MoO3:An efficient reagent system for the oxidative deprotection of semicarbazones, 1,1-diacetates and acetals
Farhad Shirini , Zahra Neyestani , Masoumeh Abedini
2009, 20(5): 514-518  doi: 10.1016/j.cclet.2009.01.039
[Abstract](188) [FullText HTML] [PDF 333KB](0)
Semicarbazones, 1,1-diacetates and acetals are efficiently converted to their corresponding carbonyl compounds using synergistic effect between KBrO3 and MoO3 in refluxing CH3CN-H2O in good to high yields.
Synthesis and characterization of mixing soft-segmented waterborne polyurethane polymer electrolyte with room temperature ionic liquid
Yue Jiao Li , Feng Wu , Ren Jie Chen
2009, 20(5): 519-522  doi: 10.1016/j.cclet.2009.01.025
[Abstract](176) [FullText HTML] [PDF 246KB](0)
Composite polymer electrolytes based on mixing soft-segment waterborne polyurethane (WPU) and 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide (BMImTFSI) have been prepared and characterized. The addition of BMImTFSI results in an increase of the ionic conductivity. At high BMImTFSI concentration (BMImTFSI/WPU=3 in weight ratio), the ionic conductivity reaches 4.27×10-3 S/cm at 30℃. These composite polymer electrolytes exhibit good thermal and electrochemical stability, which are high enough to be applied in lithium batteries.
Catalytic hydrolysis of phosphate diester (BNPP) and plasmid DNA by mononuclear macrocyclic polyamine metal complexes
Qing Xiang Xiang , Li Qun Zhang , Xiao Qi Yu , Ru Gang Xie
2009, 20(5): 523-526  doi: 10.1016/j.cclet.2009.01.001
[Abstract](182) [FullText HTML] [PDF 317KB](0)
The activities of the catalytic hydrolysis of phosphate diester (BNPP)[bis (p-nitrophenyl)phosphate diester] and plasmid DNA (pUC18) by mononuclear macrocyclic polyamine metal complexes have been investigated in this paper. The results showed that the highest activity in hydrolysis of BNPP was obtained with 1e-Zn(II) complex (composed of lipophilic group) as catalyst. The hydrolysis rate enhancement is up to 3.64×104 fold. These metal complexes could effectively promote the cleavage of plasmid DNA (pUC18) at physiological conditions.
First total synthesis of paecilodepsipeptide A
Ming Jun Yang , Jing Wu , Zhong Duo Yang , Ying Mei Zhang
2009, 20(5): 527-530  doi: 10.1016/j.cclet.2009.01.032
[Abstract](186) [FullText HTML] [PDF 275KB](0)
The first total synthesis of paecilodepsipeptide A is reported. A convergent, flexible strategy employing peptide chemistry and culminating in macrolactamisation is described. The previously reported structure of compound is confirmed.
Photopromoted carbonylation of bromobenzene under ambient conditions
Li Zhuo Mu , Ying Ping Jia , Jing Mei Yin , Guang Yun Zhou , Ying Na Cui , Da Bin Gao
2009, 20(5): 531-534  doi: 10.1016/j.cclet.2009.01.008
[Abstract](185) [FullText HTML] [PDF 239KB](0)
The photopromoted carbonylation of bromobenzene with carbon monoxide catalyzed by inexpensive commercially available cobalt salts[Co(OAc)2, CoCl2] was carried out under ambient conditions. The results revealed that methyl benzoate was produced in the presence of basic additives (CH3ONa, NaOAc or (n-C4H9)3N). The catalytic activity of Co(OAc)2 was higher than that of CoCl2. Furthermore, the activity of the carbonylation was greatly improved by addition of acetophenone, e.g. both the yield and selectivity of the ester were increased from 47% to 91% with Co(OAc)2 as catalyst and CH3ONa as additive, while the yield of byproduct benzene from hydrodehalogenation of bromobenzene decreased from 32% to 8%.
1-Heptanesulfonic acid sodium salt:One pot efficient synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles
Ganesh R. Jadhav , Mohammad U. Shaikh , Rajesh P. Kale , Charansingh H. Gill
2009, 20(5): 535-538  doi: 10.1016/j.cclet.2008.12.004
[Abstract](177) [FullText HTML] [PDF 234KB](0)
Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of 1-heptanesulfonic acid sodium salt (10 mol%) at room temperature. The reactions were performed in acetonitrile:water (8:2). The method was proved to be eco-friendly, convenient and the products were isolated with good yields (82-90%).
Covalently anchored sulfonic acid on silica gel (SiO2-R-SO3H) as an efficient and reusable heterogeneous catalyst for the one-pot synthesis of 1,8-dioxo-octahydroxanthenes under solvent-free conditions
Gholam Hossein Mahdavinia , Mohammad A. Bigdeli , Yaser Saeidi Hayeniaz
2009, 20(5): 539-541  doi: 10.1016/j.cclet.2008.12.026
[Abstract](187) [FullText HTML] [PDF 204KB](0)
A highly efficient one-pot synthesis of 1,8-dioxooctahydroxanthenes under solvent-free conditions catalyzed by sulfonic acid covalently anchored onto the surface of silica gel is reported. All types of aldehydes, including aromatic, unsaturated, and heterocyclic, are used. The silica gel/sulfonic acid catalyst (SiO2-R-SO3H) is completely heterogeneous and can be recycled.
Synthesis and antitumor activity of 7-azaindirubin
Zhao Hui Wang , Wen Yun Li , Fu Long Li , Lei Zhang , Wei Yi Hua , Jing Cai Cheng , Qi Zheng Yao
2009, 20(5): 542-544  doi: 10.1016/j.cclet.2008.12.011
[Abstract](191) [FullText HTML] [PDF 238KB](2)
Twenty 7-azaindirubin derivatives were designed and synthesized. Their antitumor activities were evaluated in vitro against DU145 cell line. The pharmacological results showed that most of the prepared compounds displayed the excellent activity.Compound 18 exhibited the most potent antitumor activity among the tested compounds.
Convenient one-pot synthesis of functionalized (E)-2-arylvinyl bromides from (E)-4-(2-bromovinyl)phenyl acetate
Yu Bo Jiang , Chun Xiang Kuang
2009, 20(5): 545-548  doi: 10.1016/j.cclet.2009.01.020
[Abstract](188) [FullText HTML] [PDF 361KB](1)
A convenient one-pot synthesis of functionalized (E)-2-arylvinyl bromides was achieved by microwave-induced deacetylation and subsequent acylation using dicyclohexyl carbodiimide (DCC) and dimethylamino-pyridine (DMAP) at room temperature from (E)-4-(2-bromovinyl)phenyl acetate.
Synthesis of rod-like bis-ester liquid crystals and their influence on photoelectric properties of liquid crystalline materials
Min Yan Zheng , Yong Sheng Wei , Zhong Wei An , Shan Wang
2009, 20(5): 549-553  doi: 10.1016/j.cclet.2008.12.058
[Abstract](182) [FullText HTML] [PDF 894KB](0)
Six novel rod-like magnetic liquid crystals have been prepared, in which trans-bicyclohexyl or trans-cyclohexylphenyl and biphenylcarboxylic acid phenyl ester mesogenic cores with n-propyl and n-pentyl substituents were terminated by 4-hydroxyl-TEMPO (TEMPO=2,2,6,6-tetramethylpiperidine-1-oxy). Their structures were confirmed by elemental analysis, IR and MS.Determined by SQUID, EPR, DSC and HS-POM (heat stage polarizing optical microscope), the six compounds all have both magnetic and liquid crystalline properties; their temperature ranges of mesophase were from 16.0 to 24.8℃, and the magnetic liquid crystal molecules could obviously improve the response sensitivity of liquid crystal materials.
The new synthesis of sesquiterpenoids 10-bromo-α-chamigrene
Qing Cui , Lin Kang , Hai Shen Yang , Xiao Hua Xu
2009, 20(5): 554-556  doi: 10.1016/j.cclet.2009.01.029
[Abstract](195) [FullText HTML] [PDF 218KB](0)
The new synthesis of 10-bromo-α-chamigrene was achieved as follows; 6-methyl-5-heptene-2-one was transformed into corresponding thioacetals, and then successively treated with Cp2Ti(P(OEt)3)2. The intermediate reacted with mono-ketal of cyclohexane-1,4-dione, and gave the carbonyl coupling product. It was then transformed into the key intermediate γ-bisabolene via deketalization, Grignard reaction, dehydration and then furnished the target molecule by polyene cyclization, with total yield 2%.All structures were confirmed by 1H NMR and 13C NMR. The final compound was confirmed by 1H NMR, 13C NMR and MS.
Microwave assisted convenient synthesis of quino[2,3-b] [1,5]benzoxazepines
Swapnil S. Sonar , Sandip A. Sadaphal , Shivaji S. Pawar , Bapurao B. Shingate , Murlidhar S. Shingare
2009, 20(5): 557-561  doi: 10.1016/j.cclet.2009.01.031
[Abstract](190) [FullText HTML] [PDF 213KB](0)
A convenient synthesis of quino[2,3-b] [1,5]benzoxazepines from substituted 2-chloroquinoline-3-carbaldehyde and 2-hydroxy aniline by using stable, non-toxic and inexpensive catalyst 1,8-diazabicyclo-undecan-7-ene (DBU)/silica gel is described. This method affords the quino[2,3-b][1,5]benzoxazepines under the influence of microwave irradiation (360 W) in solvent-free conditions within short reaction times (2-3 min), giving high yields of products (93-96%).
Synthesis and characterization of non-symmetrical liquid crystals containing a cholesteryl ester moiety
Duo Wei Zhang , Wei Huang , Guo Hui Pan , Wan Li He , Yu Bo Cao , Jin Bao Guo , Hui Cao , Huai Yang
2009, 20(5): 562-565  doi: 10.1016/j.cclet.2009.01.012
[Abstract](194) [FullText HTML] [PDF 1234KB](0)
In this paper, a series of chiral non-symmetrical liquid crystals (nBA-chol) consisting of a cholesteryl ester moiety as chiral entity and a biphenyl aromatic core with different terminal alkyl chain has been synthesized and investigated for their liquid crystalline properties. Effects of numbers of methylene units in the terminal alkyl chain on the phase transition temperatures and on the temperature-dependent pitch lengths of the chiral liquid crystals have been studied. The long terminal alkyl chain tends to exhibit smectic A mesophases. The pitch lengths of the cholesteric mesophases of the chiral liquid crystals decrease with increasing temperature and with increasing numbers of methylene units in the terminal alkyl chain, respectively.
Synthesis and cytotoxic activity of 7-alkynyl camptothecin derivatives
Feng Xiao , Yadong Xue , Yu Luo , Bo Zhang , Wei Lu , Bo Yang
2009, 20(5): 566-568  doi: 10.1016/j.cclet.2008.12.019
[Abstract](180) [FullText HTML] [PDF 203KB](0)
Several 7-alkynyl camptothecin derivatives were prepared via Sonogashira coupling. And anti-tumor activities of these compounds were evaluated against human esophageal cancer cell line (Eca-109), human chronic myeloid leukaemia cell line (K562), bladder cancer cell line (5637) and gastric cell line (SGC7901). Compounds 9a-d and 10a exhibited remarkable in vitro cytotoxic activity, compared with topotecan.
A new triterpenoid saponin from Bacopa monniera
Yun Zhou , De Yun Kong , Ling Peng , Wei Dong Zhang
2009, 20(5): 569-571  doi: 10.1016/j.cclet.2009.01.004
[Abstract](186) [FullText HTML] [PDF 203KB](0)
A new triterpenoid saponin, bacopaside IX, was isolated from the whole plant of Bacopa monniera (L.) Wettst. and its structure was elucidated as 3-O-{β-d-glucopyranosyl(1→4)[α-l-arabinofuranosyl-(1→2)]-b-d-glucop-yranosyl}-20-O-α-l-arabinopyranosyljujubogenin by spectroscopic methods and some chemical transformations.
Two new triterpenes from Duchesnea indica
Wei Qiao , Zhi Yao , Wen Zhang , Hong Quan Duan
2009, 20(5): 572-575  doi: 10.1016/j.cclet.2008.12.052
[Abstract](180) [FullText HTML] [PDF 242KB](0)
Two new triterpenes, 2α,3β-dihydroxy-urs-12-en-18,19-epoxy-28-oic acid (1) and 18,19-seco,2α,3α-dihydroxyl-19-oxo-urs-11,13(18)-dien-28-oic acid (2) were isolated from the herbaceous part of Duchesnea indica. Their structures were elucidated by spectroscopic analysis, including 2D NMR technique. The isolated compounds exhibited moderate cytotoxic activities against HeLa and L929 cell lines.
A new chalcone from the aerial roots of Ficus microcarpa
Hui Xu , Xiang Min Wang , Xing Wei , Jing Yuan Li , Ke Liu
2009, 20(5): 576-578  doi: 10.1016/j.cclet.2009.01.013
[Abstract](178) [FullText HTML] [PDF 239KB](0)
A new flavonoid with chalcone skeleton was isolated from the dried aerial roots of Ficus microcarpa. The structure of the compound was elucidated on the basis of spectral methods including 1D and 2D NMR. The new compound showed weak inhibitory effect on nitric oxide production and cytotoxicity against K562 and PC3 cells.
Two new flavanone glycosides from Macrothelypteris torresiana (Gaud.) Ching
Wei Fu , Wei Fang , Jin Lan Ruan
2009, 20(5): 579-581  doi: 10.1016/j.cclet.2008.12.025
[Abstract](173) [FullText HTML] [PDF 222KB](0)
Two new flavanone glycosides 1 and 2 were isolated from the aerial parts of Macrothelypteris torresiana (Gaud.) Ching. The structures of two products were identified as (2S)-5,7,2',5'-tetrahydroxyflavanone-20-O-β-D-6"-O-acetylglucopyranoside and (2S)-5,7,2',5'-tetrahydroxyflavanone-2'-O-β-D-glucopyranoside on the basis of their chemical and spectral analysis, respectively.
Synthesis of di-and tetrasaccharide containing 6-deoxytalose from the O-antigenic polysaccharide of B. pseudomallei strain 304b
Shi Qiang Yan , Xue Min Wu , Xiao Mei Liang , Jian Jun Zhang , Dao Quan Wang
2009, 20(5): 582-585  doi: 10.1016/j.cclet.2009.01.007
[Abstract](191) [FullText HTML] [PDF 347KB](0)
Synthesis of the disaccharide β-D-Glup-(1→3)-6-deoxy-α-L-Talp II, and its dimer III from the O-antigenic polysaccharide of Burkholderia pseudomallei strain 304b, were achieved through assembly of suitably synthesized building blocks, 4-methoxylphenyl 6-deoxy-2,4-di-O-benzoyl-α-L-talopyranoside (7), 3-O-allyl-2,4,6-tri-O-benzoyl-α,β-D-glucopyranosyl trichloroacetimidate (8) and 2,3,4,6-tetra-O-benzoyl-α,β-D-glucopyranosyl trichloroacetimidate (11). The total yield of III from 4-methoxylphenyl 2,3-O-isopropylidene-α-L-rhamnopyranoside (1) was 18%.
A new nor-sesquiterpene lactone from Ainsliaea fulvioides
Yan Wang , Ming Lu Xu , Hui Zi Jin , Jian Jun Fu , Xiao Jia Hu , Jiang Jiang Qin , Shi Kai Yan , Yun Heng Shen , Wei Dong Zhang
2009, 20(5): 586-588  doi: 10.1016/j.cclet.2009.01.016
[Abstract](176) [FullText HTML] [PDF 267KB](0)
A new nor-sesquiterpene lactone ainsliatone A (1) was isolated from the aerial parts of Ainsliaea fulvioides. Its structure was established by the basis of spectroscopic methods and single-crystal X-ray diffraction analysis.
A new lignan from Gynostemma pentaphyllum
Xiao Wen Wang , Hua Ping Zhang , Feng Chen , Xi Wang , Wei Ye Wen
2009, 20(5): 589-591  doi: 10.1016/j.cclet.2009.01.034
[Abstract](179) [FullText HTML] [PDF 231KB](1)
A new lignan ligballinone 1 with the know ligballinol 2 were isolated from plant Gynostemma pentaphyllum. Their structures were determined through spectroscopic methods including ESI-MS, 1D and 2D NMR (1H, 13C, DEPT, 1H-1H COSY, HMQC,HMBC) and X-ray diffraction experiment for 2.
A new coumarin from Wikstroemia indica (L.) C. A. Mey
Yang Chen , Wen Wei Fu , Li Xin Sun , Qia Wang , Wei Qi , Hua Yu
2009, 20(5): 592-594  doi: 10.1016/j.cclet.2009.01.002
[Abstract](186) [FullText HTML] [PDF 196KB](0)
A new coumarin was obtained from the stems and roots of Wikstroemia indica (L.) C. A. Mey. Its structure was elucidated as methyl 3-(2-hydroxy-4-(7-hydroxy-6-methoxy-2-oxo-2H-chromen-3-yloxy) phenyl) propanoate by spectroscopic methods.
A new flavonoid from Selaginella tamariscina
Jian Feng Liu , Kang Ping Xu , De Jian Jiang , Fu Shuang Li , Jian Shen , Ying Jun Zhou , Ping Sheng Xu , Bin Tan , Gui Shan Tan
2009, 20(5): 595-597  doi: 10.1016/j.cclet.2009.01.005
[Abstract](176) [FullText HTML] [PDF 189KB](0)
6-(2-Hydroxy-5-acetylphenyl)-apigenin (1), a new flavonoid with a phenyl substituent, was first isolated from Selaginella tamariscina. Its structure was elucidated on the basis of 1D and 2D NMR as well as ESI-HR-MS spectroscopic analysis.
Monoterpene and tetrahydronaphthene derivatives from Senecio argunensis
Chao Feng Zhang , Ning Li , Lin Li , Mian Zhang
2009, 20(5): 598-600  doi: 10.1016/j.cclet.2009.01.017
[Abstract](181) [FullText HTML] [PDF 378KB](0)
Two new compounds, senarguines A and B, were isolated from Senecio argunensis. They were respectively identified as (Z)-3-ethylidene-9-hydroxyl-9-methyl-6,7-dioxaspiro[4.4] nonane-5,8-dione (1) and 3,6,6-trimethyl 6,7,8-tetrahydronaphtha-[1,2b] furan (2) on the basis of spectral data.
Schisanlactone G, a new 3,4-seco-lanostane triterpenoid from Schisandra sphenanthera
Rong Ren , Guo Jun Luo , Hong Mei Li , Zhao Yuan Wu , Hai Zhou Li , Rong Tao Li
2009, 20(5): 601-603  doi: 10.1016/j.cclet.2008.12.053
[Abstract](182) [FullText HTML] [PDF 238KB](0)
A new 3,4-seco-lanostane triterpenoid, schisanlactone G (1), was isolated from the fruits of Schisandra sphenanthera. Its structure was established on the basis of extensive spectroscopic analysis.
Poly(vinylpyridine) adsorbent for the removal of SIPA from its aqueous solution
Wei Hua Tao , Ai Min Li , Chao Long , Hong Ming Qian
2009, 20(5): 604-607  doi: 10.1016/j.cclet.2008.12.029
[Abstract](165) [FullText HTML] [PDF 225KB](0)
Poly(vinylpyridine) WH-225 resin was prepared and characterized. Compared with the commercial hypercrosslinked adsorbent NDA-100 and macroporous adsorbent XAD-4 resins, the newly synthesized poly(vinylpyridine) WH-225 resin exhibited the highest adsorption capacity toward SIPA from aqueous solution.
Methane sensor based on palladium/MWNT nanocomposites
Zhong Ping Li , Yong Guo , Suo Zhu Wu , Shao Min Shuang , Chuan Dong
2009, 20(5): 608-610  doi: 10.1016/j.cclet.2008.12.031
[Abstract](178) [FullText HTML] [PDF 252KB](0)
Methane gas sensor was fabricated based on electrocatalytic properties of the Pd/MWNT nanocomposites on indium tin oxide (ITO) glass substrates. A linear response for methane was obtained in the range of 0-16% (v/v) with a detection limit of 0.167% (v/v) and R.S.D. of 4.1%. After 100 times sensing or stable stored more than 12 months in atmosphere, unconspicuous measurable decrease was observed. The response time was less than 60 s at room temperature and ambient pressure. Some common potential interferents in samples such as N2, CO, CO2, ethane, propane, pentane, methanol, ethanol, H2 and NH3 were investigated and all the effects were less than 5% on the response for 3.0% (v/v) methane. The sensor was applied to methane determinations in man-made gas samples, the results are satisfied.
Selectively colorimetric detection of cysteine with triangular silver nanoprisms
Tong Wu , Yuan Fang Li , Cheng Zhi Huang
2009, 20(5): 611-614  doi: 10.1016/j.cclet.2009.01.024
[Abstract](202) [FullText HTML] [PDF 1407KB](0)
Triangular silver nanoprisms were prepared and applied to make colorimetric detection of cysteine based on our findings that cysteine could lead to the blue shift of the dipole plasmon resonance absorption, but other 19 kinds of natural amino acids could not.Cysteine with a concentration 160 nmol/L can result in a color change that can be discerned with naked eyes.
Simultaneous spectrophotometric determination of four preservatives in foodstuffs by multivariate calibration and artificial neural networks
Yan Qing Chen , Yong Nian Ni
2009, 20(5): 615-619  doi: 10.1016/j.cclet.2009.01.006
[Abstract](174) [FullText HTML] [PDF 252KB](0)
Benzoic acid (BA), methylparaben (MP), propylparaben (PP) and sorbic acid (SA) are food preservatives, and they have well defined UV spectra. However, their spectra overlap seriously, and it is difficult to determine them individually from their mixtures without preseparation. In this paper, seven different chemometric approaches were applied to resolve the overlapping spectra and to determine these compounds simultaneously. With respect to the criteria of% relative prediction error (RPE) and% recovery,principal component regression (PCR) and radial basis function-artificial neural network (RBF-ANN) were the preferred methods.These two methods were successfully applied to the analysis of some commercial samples.
Nonlinear optical properties of novel H-shaped chromophores
Chao Zhi Zhang , Guo Yuan Lu , Chang Shun Wang
2009, 20(5): 620-622  doi: 10.1016/j.cclet.2009.01.030
[Abstract](181) [FullText HTML] [PDF 248KB](0)
Novel and effective H-shaped chromophores were doped into polymethyl methacrylate (PMMA) to form guest-host polymer thin films. The measurement results of Maker fringe method show that the polymer thin films containing the H-shaped chromophores as a guest exhibit high second harmonic coefficients (d33) compared with other two-dimensional chromophores.
Large enhancements in gelation behavior of wheat gliadins by incorporation of low concentrations of methylcellulose
Yi Hu Song , Ling Fang Li , Qiang Zheng
2009, 20(5): 623-626  doi: 10.1016/j.cclet.2009.01.022
[Abstract](199) [FullText HTML] [PDF 281KB](0)
Influence of non-gelling methylcellulose (MC) on gelation behavior of wheat gliadins in 13 wt% alkaline propanol/water (50:50,v/v) solution was investigated using dynamic rheological time sweep test. Increasing MC concentration (CMC) up to CMC=1 wt% caused a significant reduction in gelation time (tgel) of the solution and an increase in loss tangent (tan δ) value of the resultant gel at T < 30℃.
Polymeric complex micelle loaded with axially substituted silicon(IV) phthalocyanine
Bao Quan Huang
2009, 20(5): 627-630  doi: 10.1016/j.cclet.2009.01.026
[Abstract](171) [FullText HTML] [PDF 530KB](0)
A novel axially substituted silicon(IV) phthalocyanine, namely di-pyridyloxy axially substituted silicon(IV) phthalocyanine 2 was synthesized and characterized by UV/vis, IR, elemental analysis, MS as well as 1H NMR spectroscopy. Hydrophobic 2 was encapsulated by amphiphilic triblock copolymer poly[Nε-(benzyloxycarbonyl-lysine]-poly(ethylene glycol)-poly[Nε-(benzyl oxycarbonyl) (PLL(Z)-b-PEG-b-PLL(Z)) to form hydrophobic 2-loaded polymeric complex micelle (PIC) (2-loaded PIC). Atom force microscopy (AFM) image showed that 2-loaded PIC formed a spherical nanocarrier with approximately 35-50 nm in diameter. The fluorescence intensity and lifetime of 2-loaded PIC was significantly enhanced by the incorporation 2 into PIC nanocarrier.
Dynamic consequences of mutating the typical HPGG motif of apocytochrome b5 revealed by computer simulation
Ying Wu Lin , Tian Lei Ying , Li Fu Liao
2009, 20(5): 631-634  doi: 10.1016/j.cclet.2009.01.037
[Abstract](191) [FullText HTML] [PDF 1506KB](0)
Apocytochrome b5 with a typical heme-binding motif of HPGG, and its variants with mutated motifs, GPGG, GPGH, HVGG,and HPGP, have been subjected to molecular dynamics simulation. Comparison of the dynamic consequences has revealed the crucial role of HPGG in assembling the heme group of cytochrome b5 and in modulating protein structure, property and function.
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