Zhu R.-X.,Key Laboratory of Colloid and Interface Chemistry |
Zhang D.-J.,Key Laboratory of Colloid and Interface Chemistry |
Guo J.-X.,Key Laboratory of Colloid and Interface Chemistry |
Mu J.-L.,Key Laboratory of Colloid and Interface Chemistry |
And 2 more authors.
Journal of Physical Chemistry A | Year: 2010
A computational study with the B3LYP density functional theory was carried out to study the reaction mechanism for the cycloisomerization of allenes catalyzed by Au(I) and Au(III) complexes. The catalytic performance of Au complexes in different oxidation states as well as the effects of the counterion on the catalytic activities has been studied in detail. Our calculations show that the catalytic reaction is initiated by coordination of the Au(I) or Au(III) catalyst to the distal double bond of allene and activation of allene toward facile nucleophilic attack, then 3-pyrroline obtained via two-step proton shift, followed by demetalation. On the basis of our calculations, H shifts are key steps of the catalytic cycle, which are significantly affected by the gold oxidation state, counterion, ligands, and assistant catalyst. AuCl is found to be more reactive than AuCl3; however, the Au(III)-catalyzed path does not involve an oxidation state change from Au(III) to Au(I). Our calculated results rationalize the experimental findings well and overthrow the previous conjecture about Au(I) serving as the catalytically active species for Au(III)-catalyzed cycloisomerization. © 2010 American Chemical Society.
Jia Y.,Shandong Institute of Pharmaceutical Industry |
Zhang J.,Shandong University |
Feng J.,Shandong Academy of Sciences |
Xu F.,Shandong University |
And 2 more authors.
Chemical Biology and Drug Design | Year: 2014
A novel series of pazopanib derivatives were designed, synthesized, and evaluated for their inhibitory activity against a series of kinases including VEGFR-2, EGFR, AKT1, ALK1, and ABL1. The anti-angiogenic activities ex vivo of some compounds were also investigated. Compounds P2d and P2e demonstrated outstanding inhibitory activity against VEGFR-2 and ABL1 and higher anti-angiogenic activity compared with Pazopanib, the reference standard. These two compounds (P2d and P2e) could be used as novel lead compounds for further development of anticancer agents. © 2013 John Wiley & Sons A/S.
Shao H.,Shandong University |
Shao H.,Institute of Biopharmaceuticals of Shandong Province |
Han G.,Shandong University |
Han G.,Institute of Biopharmaceuticals of Shandong Province |
And 13 more authors.
Carbohydrate Polymers | Year: 2013
The objective of this study was to evaluate the alleviative effect of intra-articular (IA) injection of xanthan gum (XG) on pain and cartilage degradation in a model of monosodium iodoacetate (MIA)-induced knee osteoarthritis (OA). The rheological study and hyaluronidase (HAse) degradation analysis of XG injection were presented. The effect of pain relief was determined by measurements of paw withdrawal threshold and weight bearing by hind limbs. The protective effect on the cartilage was evaluated by gross morphological observation and histological evaluation of knee joints. The effect was investigated in two protocols: a therapeutic treatment protocol, and a prophylactic treatment protocol. Our results showed that HAse had no effect on the rheological properties of XG injection. Local XG administration in both protocols could reduce OA pain and alleviate the joint cartilage degradation induced by MIA. IA injection of XG might be an effective method for OA treatment in human. © 2012 Elsevier Ltd.
Lv P.-L.,Shandong University |
Zhu R.-X.,Shandong University |
Zhang D.-J.,Shandong University |
Duan C.-G.,Shandong Institute of Pharmaceutical Industry |
Liu C.-B.,Shandong University
Journal of Physical Chemistry A | Year: 2012
The asymmetric epoxidation of 2-cyclohexen-1-one with aqueous H 2O 2 as oxidant, 1,2-diaminocyclohexane as catalyst, and a Brønsted acid trifluoroacetic acid (TFA) as cocatalyst has been studied by performing density functional theory calculations. It is confirmed that the catalyzed epoxidation proceeds via sequential nucleophilic addition and ring-closure processes involving a ketiminium intermediate. Four possible pathways associated with two Z isomers and two E isomers of ketiminium have been explored in detail. Our calculation indicates that these four pathways have high barriers and a small energy gap between two more favorable R and S pathways. We have analyzed the effects of the TFA anion and H 2O on the activity and enantioselectivity of catalytic epoxidation. It is found that the TFA anion acts as a counterion to stabilize the transition states of the catalytic epoxidation by hydrogen-bond acceptance, leading to decreases in the barriers of the nucleophilic addition and ring-closure processes. The most significant decrease occurred in the ring-closure step of the Z-R-pathway, resulting in H-bond-induced enantioselectivity. Our calculations also show that water cooperates with TFA to further increase the reaction rate significantly. © 2011 American Chemical Society.
Zhang Y.,Shandong University |
Liu C.,Shandong University |
Chou C.J.,Medical University of South Carolina |
Wang X.,Postdoctoral Workstation |
And 2 more authors.
Chemical Biology and Drug Design | Year: 2013
In our previous study, we developed a novel series of tetrahydroisoquinoline-based hydroxamic acid derivatives as histone deacetylase inhibitors (Bioorg Med Chem, 2010, 18, 1761-1772; J Med Chem, 2011, 54, 2823-2838), among which, compound ZYJ-34c (1) was identified and validated as the most potent one with marked in vitro and in vivo antitumor potency (J Med Chem, 2011, 54, 5532-5539.). Herein, further modification in 1 afforded another oral active analog ZYJ-34v (2) with simplified structure and lower molecular weight. Biological evaluation of compound 2 showed efficacious inhibition against histone deacetylase 1, 2, 3, and 6, which was confirmed by Western blot analysis results. Most importantly, compound 2 exhibited similar even more potent in vitro and in vivo antitumor activities relative to the approved histone deacetylase inhibitor SAHA. Structural modification of 1 led to another oral active HDACi 2 with simplified structure and lower molecular weight. Compared with the approved HDACi SAHA, 2 exhibited similar even superior in vitro and in vivo antitumor potency.© 2013 John Wiley and Sons A/S.