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Betulinic acid (BA) is a new class of anticancer drug, but its relatively short half-life and poor water solubility limit its therapeutic effect and clinical application. Herein, to tackle the dilemma, BA prodrugs were prepared by conjugating BA onto the polyethylene glycol (PEG) polymer via cleavable disulfide bonds. The prodrugs exhibited high water solubility (270-fold of free BA) and a relatively high drug-loading efficiency of 14.2 %. To further endow the BA prodrugs with a photothermal therapeutic effect, the near-infrared (NIR) agent Cypate was grafted on the Pluronic triblock copolymer. The different PEG polymers and different Pluronic polymers were chosen to obtain the optimal drug loading efficiency and the photothermal generation effect. The P-SS-BA/F68-Cy prodrug micelles integrate the redox-responsive BA prodrugs and the NIR-responsive amphiphilic triblock polymer into one single nanocomposite. The release of BA was less than 20 % in pH 7.4 PBS in the absence of glutathione (GSH), whereas the release of BA was obviously accelerated in pH 5.0 PBS with 10 mM GSH. In addition, the release of BA was further accelerated under the NIR irradiation. The P-SS-BA/F68-Cy micelles showed an excellent photothermal heating effect under NIR irradiation. The prepared P-SS-BA/F68-Cy micelles showed the synergistic thermochemotherapeutic effect on tumors both in vitro and in vivo. Therefore, the present study shows the great potential of dual-triggered drug delivery and thermochemotherapy for combination therapy.

A series of novel 2,3-diarylthiophene analogues of combretastatin A-4 (CA-4) were designed with a rigid thiophene moiety to retain the cis-olefin configuration of CA-4 and were subsequently synthesised. All of the target compounds were evaluated for their in vitro anti-proliferative activities. Among these compounds, 5f and 8d exhibited superior potency against different tumour cell lines with IC50 values at sub-micromolar levels. Moreover, compound 8d significantly inhibited tubulin polymerisation to microtubules and caused microtubule destabilisation. In addition, a molecular modelling study of compound 8d was performed to clarify its binding mode at the colchicine site in the tubulin dimer and to provide a basis for further structure-guided design of novel CA-4 analogues.

Two series of benzamides compounds bearing piperidine groups were synthesized and the Gli-luc luciferase activity was screened by Gys-luc luciferase gene detection method. Compound 5q showed promising inhibition of hedgehog (Hh) signaling pathway. To further verify whether the Hh inhibitory activities of the target compounds are derived from their inhibition to the Smoothened (Smo) receptor, the compounds with good potency were evaluated in a fluorescence competitive displacement assays, the results showed the Smo inhibitory potency of these compounds correlated well with their Hh inhibition, which suggested that the observed Hh activity was driven by Smo inhibitors.

A series of pyrrolopyrazinone-chalcone hybrids(12a–12q) was designed, synthesized and screened for their antitumor activity against SKOV-3, A549 and HeLa cell lines in vitro. Compared with the pyrrolopyrazinone( 10a) and 5-fluorouracil(5-FU), nearly all the tested compounds showed significantly-improved antitumor activities. The most promising compounds 12e and 12k(IC50=0.25 and 0.88 μmol/L) respectively show activities of 123 and 35 times that of compound 10a(IC50=30.74 μmol/L) against HeLa cell line. The result reveals that the presence of chalcone moiety is beneficial to their activity and selectivity.

A highly enantioselective domino reaction of α,β-unsaturated aldehydes and 4-acetyl-5-oxohexanal catalyzed by a chiral secondary amine catalyst has been developed, providing an efficient synthetic approach for the synthesis of densely functionalized chiral cyclohexene derivatives with high yields (up to 96%) and enantioselectivities (up to 97% ee) under mild conditions.

Combretastatin A-4 (CA-4), its analogues and their excellent antitumoral and antivascular activities, have attracted considerable interest of medicinal chemists. In this article, a docking simulation was used to identify molecules having the same binding mode as the lead compound, and 3D-QSAR models had been built by using CoMFA based on docking. As a result, these studies indicated that the QSAR models were statistically significant with high predictabilities (CoMFA model, q2 = 0.786, r2 = 0.988). Our models may offer help to better comprehend the structure-activity relationships for this class of compounds and also facilitate the design of novel inhibitors with good chemical diversity.

Merrifield resin supported cinchona ammonium salts bearing 2′-fluorobenzene, 2′-cyanobenzene and 2′- N -oxypyridine groups were prepared and applied to the phase-transfer catalytic alkylation of N -(diphenylmethylene)glycine tert -butyl ester for the enantioselective synthesis of α-amino acids (76–96% ee).

The domino reaction of hexanal derivative (I) with α,β-unsaturated aldehydes proceeds in the presence of a chiral diphenylsilylprolinol catalyst under mild conditions to give cyclohexene derivatives in good yields and with high enantioselectivities.

Retinoic acid receptor-related orphan receptor γ (RORγ), a member of the nuclear hormone receptor superfamily, is a promising therapeutic target for treating Th17-mediated autoimmune diseases. We performed structure-based virtual screening targeting the RORγ ligand-binding domain. Among the tested compounds, s4 demonstrated RORγ antagonistic activities with micromolar IC50 values in both an AlphaScreen assay (20.27 μM) and a cell-based reporter gene assay (11.84 μM). Optimization of the s4 compound led to the identification of compounds 7j, 8c, 8k, and 8p, all of which displayed significantly enhanced RORγ inhibition with IC50 values of 40–140 nM. These results represent a promising starting point for developing potent small molecule RORγ inhibitors.

A novel series of N-sulfonyl homoserine lactone derivatives 5a–l has been designed, synthesized and evaluated for quorum sensing inhibitory activities towards violacein production. Of the compounds synthesized, compound 5h was found to possess an excellent level of enantiopurity (99.2% e.e.). The results indicated that compounds bearing an ortho substituent on their phenyl ring exhibited excellent levels of inhibitory activity against violacein production. Compounds 5h and 5k in particular, with IC50 values of 1.64 and 1.66 µM, respectively, were identified as promising lead compounds for further structural modification.

A series of novel compounds bearing imidazo[2,1-b]thiazole scaffolds were designed and synthesized based on the optimization of the virtual screening hit compound N-(6-morpholinopyridin-3-yl)-2-(6-phenylimidazo[2,1-b]thiazol-3-yl)acetamide (5a), and tested for their cytotoxicity against human cancer cell lines, including HepG2 and MDA-MB-231. The results indicated that the compound 2-(6-(4-chlorophenyl)imidazo[2,1-b]thiazol-3-yl)-N-(6-(4-(4-methoxybenzyl)piperazin-1-yl)pyridin-3-yl)acetamide (5l), with slightly higher inhibition on VEGFR2 than 5a (5.72% and 3.76% inhibitory rate at 20 μM, respectively), was a potential inhibitor against MDA-MB-231 (IC(50) = 1.4 μM) compared with sorafenib (IC(50) = 5.2 μM), and showed more selectivity against MDA-MB-231 than HepG2 cell line (IC(50) = 22.6 μM).

Merrifield resin-supported hydrocinchonidinium salts containing particular functional groups that can participate in hydrogen bonding were prepared and evaluated as chiral phase-transfer catalysts ...

Merrifield resin supported cinchona ammonium salts bearing 2′-fluorobenzene, 2′-cyanobenzene and 2′- N -oxypyridine groups were prepared and applied to the phase-transfer catalytic alkylation of N -(diphenylmethylene)glycine tert -butyl ester for the enantioselective synthesis of α-amino acids (76–96% ee).

To study the morphological characteristics of hepatic stem cells and the expression of HGF, IGF-I, TGFbeta1 and their receptors in human embryonic livers at 3-5 weeks of gestation. The SABC immunohistochemical method with HE counterstaining was employed. We found that the hepatic bud formed at the end of the 3rd week. At the 4th week, the cells of hepatic bud migrated into the septum transversum mesenchyme and formed the hepatic cords. The hepatic cells at 3-4 weeks displayed the typical characteristics of immature cells: small size, a round or ovoid nucleus with dark color, scant cytoplasm with slight blue and a high ratio of nuclei/cytoplasm. They were positive for alpha-Fetoprotein (AFP), c-Met and negative for cytokertin 19 (CK19), and proliferating cell nuclear antigen (PCNA). At the 5th week, compared to those at the 4th week, the number of cells within the hepatic cords increased. But the cells at the 5th week were homogeneous and displayed the typical characteristic of immature cells. Those cells began to express PCNA at the 5th week. The hepatic cells at the 5th week were positive for insulin-like growth factor I (IGF-I), transforming growth factor beta1 (TGFbeta1) and their receptors, and were negative for hepatocyte growth factor (HGF), while HGF were positive in the cardiac cells and septum transversum mesenchyme. The results indicated that the cells of hepatic bud and cords were the hepatic stem cells. The difference of morphology and proteins expression at 3-5 weeks of gestation inferred that those stem cells belong to different developmental stage. AFP and c-Met were the markers of hepatic stem cells at the early stage of human embryo. HGF, IGF-I, TGFbeta1 and their receptors may involve in regulating the development of early embryonic human liver.

Merrifield resin-supported hydrocinchonidinium salts containing particular functional groups that can participate in hydrogen bonding were prepared and evaluated as chiral phase-transfer catalysts ...