Photo-isomerization of aromatic α-hydroxy hydrazone was reported. We investigated the structures of salicylaldehyde phenylhydrozone（SP） in the ground state using density functional theory（DFT） with the B3LYP functional and the 6-311＋G（d） basis set. All nine possible isomers of SP in the ground state consist of seven phenol forms and two ketone forms. Intrisic reaction coordinate（IRC） analysis discloses the existence of a cycle driven by the two proton transfer processes in the ground and excited states of SP, which suggests that no ketonic form could exist in the ground state. Further theoretical studies of the potential energy surfaces support a trans-cis conversion followed by a relaxation to the stable form of SP in the excited states.
JIN Jing-yiPAN YanLI Xiu-huaHOU JunWU XueSU Zhong-min
Hollow calcium carbonate（CaCO3） microspheres with different morphologies were synthesized via the precipitation reaction of calcium chloride with sodium carbonate in the presence of different surfactant-polymer complexes.The selected anionic surfactants were sodium dodecyl sulfonate（SDS） and sodium dodecyl benzenesulfonate（SDBS）,respectively.The selected water-soluble polymers were polyacrylic acid（PAA） and polyvinyl pyrrolidone（PVP）.In this work,SDS-PVP ＂pearl-necklace model＂ micellar complex was formed via hydrophobic effectiveness between SDS and PVP and it served as the spherical template to generate spherical CaCO3 aggregates with hollow microspheres composed of about 500 nm irregular shaped particles.SDS-PAA complexes and SDBS-PAA complexes formed ＂core-shell model＂ aggregates with calcium ions serving as the medium to link the anionic surfactant and the polymer.SDS-PAA ＂core-shell model＂ aggregates would act as templates for hollow CaCO3 microspheres consisting of 30―50nm irregular shaped crystallites.SDBS-PAA ＂core-shell model＂ aggregates served as the spherical aggregate templates to generate spherical CaCO3 aggregates consisted of many small spherical particles which had grown together.All the obtained CaCO3 hollow microspheres are calcite particles.This research may provide new insight into the control of morphologies of hollow CaCO3 microspheres in the presence of surfactantpolymer complexes.
Two crosslinkable poly（p-phenyleneethynylene）s（PPEs）： poly[2,5-di（2＇-ethyl-hexyloxy）-1,4-phenylenecthynylene] with end-capped vinyl（PPE1） and poly[2,5-di（allyloxy）-1,4-phenyleneethynylene-2,5-di（2＇-ethyl-hexyloxy）-1,4-phenyleneethynylene]（PPE2） were synthesized. Via the thermal addition reactions of vinyl end groups of PPE1 and allyloxy side groups of PPE2, crosslinked polymers C-PPE1 and C-PPE2 were obtained, respectively. The two polymers were characterized by wide-angle X-ray diffraction（WXRD）, ultraviolet-visible（UV-Vis） absorption, and photoluminescence（PL）. The results indicate that in the solid state, the polymer chains of PPE1 were packed with a low degree of crystallinity because of the sterically hindered（2＇-ethyl-hexyl）oxy branched side chains, but, because of the introduction of allyloxy side chains, the polymer chains of PPE2 were packed in an order fashion with a high degree of crystallinity. Because of the high crosslinking density in C-PPE2, the formation of aggregates and excimer was hampered by the formed crosslinking network more effectively in C-PPE2 film than in C-PPE1 film.
Eighteen novel triazole compounds containing 1,3,4-oxadiazole groups were synthesized from 2-（1H-1,2,4-triazol-1-yl）acetohydrazide and carbon disulfide by several step reactions. The target compounds were characterized by elemental analysis, 1H NMR, 13C NMR, IR, MS, and X-ray crystallography. The results of preliminary biological tests show that all the compounds exhibit certain fungicidal activities.
XU Liang-zhong BI Wen-zhao SHANG Yu-qing ZHAI Zhi-wei YI Xu
Conductive polyvinylidene fluoride（PVDF）matrix composites filled with graphited fiber（GF）or carbon fiber（CF）were prepared by the melt-mixing method.The breakage and length distribution of the fibers in the polymer matrix were studied by scanning electron microscope（SEM）and optical microscope（OM）observations,respectively. The differences in the positive temperature coefficient（PTC）effects of the composites were mainly attributed to inter-fiber contact ability.The elimination of the negative temperature coefficient（NTC）effect for CF/PVDF composite was because of an increase in the viscosity of the polymer matrix.With the same filler content,CF could be more effective,to eliminate the NTC effect when compared with GF.Addition of 2%CF（mass fraction）in the PVDF composite with 7%GF（mass fraction）could effectively eliminate the NTC phenomenon of the composite.
WANG Xin-lei ZHANG Guo LI Ji-xin LI Zhuo-shi LIU Zhan-fang LIU Xiu-qi
A novel series of first procaspase activating compound（PAC-1） analogues was designed, synthesized and evaluated for antitumor activity towards two cell lines[human promyelocytic leukemia cell line（HL60） and human embryonic lung fibroblast cell line（HLF）] by the MTT[3-（4,5）-dimethylthiahiazo（-z-yl）-3,5-di-phenytetrazo- liumromide] method in vitro. The structures of all the compounds were confirmed by IH NMR, MS and elemental analysis. Among the compounds synthesized^（E）-2-[（3-{[4-（tert-buty~）benzy~]（methy~）amin~}pr^py~）（methy~）amin~]- N＇-[4-（diethylamino）-2-hydroxybenzylidene]acetohydrazide（compound 6n） exhibits a good anti-proliferative activity to the majority of tumor cells tested, and selectively cleaves cancer cells. Thus, compound 6n was identified as promising lead compound for further structural modification.
LUO Hao-mingYANG Chun-lingZHANG Xiao-yingZHAO Ming-mingJIANG DanXIAO Jun-haiYANG Xiao-hongLI Song
A novel nickel（II）-complex Ni[L]Cl2-CH3CN（1） containing the tridentate ligand 2,6-bis[1-（2,4,6- trimethylphenylimino）ethyl]pyridine（L） has been synthesized. The crystal structure of complex 1 was determined by single crystal X-ray diffraction analysis. The catalytic activity of complex 1 for the polymerization of ethylene was studied under activation with methylaluminoxane（MAO）.
To overcome ampicillin-resistance of bacteria which is believed to attribute their endogenous B-lactamase, we designed three 10-23 DNAzymes（Dz1, Dz2. Dz3） targeting the coding region of B-lactamase mRNA and examined their inhibitory capabilities of the ampicillin-resistance of TEM-1 and TEM-3 bacteria. Dz1 was a traditional 10-23 DNAzyme, Dz2 was the mutant of Dz1 by addition of the protected nucleotide to each ann of the enzyme, and Dz3 was a mutant of Dz1 at antisense arms of which phosphorothioate modifications were made. Kinetic analysis, bacterial growth, and β-lactamase activity measurement showed that all the three DNAzymes worked efficiently in vitro and in vivo. A 9 hours bacterial growth inhibition test showed that the inhibition rates of TEM-1 bacteria by Dz1, Dz2, and Dz3 were 27%, 50%, and 29%, respectively. In addition, the inhibition rates of TEM-3 bacteria by those three DNAzymes were found io be 49%, 58%, and 45%, respectively. The current findings suggest that DNAzymes may become potential candidates of alternative inhibitors for bacteria drug-resistance.
Six Brnsted acidic ionic liquids（ILs） 1a―1f were synthesized and used as the dual solvent-catalyst systems for Beckmann rearrangement reactions. Among ILs 1a―1f, IL 1a exhibited the highest catalytic activity and successfully catalyzed the Beckmann rearrangement of ketoximes, and the corresponding amides were obtained in good to excellent yields（74%―92%）. In addition, IL 1a could be recovered easily and reused at least three times without any loss of catalytic activity.
WU Mao-cheng DUAN Hai-feng CAO Jun-gang LIANG Da-peng JIANG Feng GAO Han JIA Xu-dong LIN Ying-jie
Ficin is an important component of plants in Ficus family such as fig latex. It is of special significance in medicine and industry because it exhibits activity throughout a wide range of temperature and pH values. In this work, we purified a component of ficin from the latex homogeneity of Shandong fig trees, and the properties of the purified ficin were studied. The current findings revealed that heavy metal ions were able to inhibit ficin, while DTT, L-cysteine, and β-ME were found to promote ficin activity. It was also observed that the half life of ficin at 65 °C was longer than 1 h and the Michaelis constant（Km） for casein hydrolyzation was determined to be 1.56 mg/mL. Our study shows that this purified ficin is a cysteine protease.
HUANG Lu QU He-zhi ZHANG Lei DU Shan-shan YANG Shuo HAO Dong-yun WANG Xiao-ping
