En Zhang

Design and synthesis of novel 1,2,3-triazole-dithiocarbamate hybrids as potential anticancer agents

A series of novel 1,2,3-triazole-dithiocarbamate hybrids were designed, synthesized and evaluated for anticancer activity against four selected human tumor cell lines (MGC-803, MCF-7, PC-3, EC-109). Majority of the synthesized compounds exhibited moderate to potent activity against MGC-803 and MCF-7. Among them, compounds 3a and 3c showed excellent broad spectrum anticancer activity with IC50 values ranging from 0.73 to 11.61 μM and 0.49-12.45 μM, respectively. Particularly, compound 3a was more potent than 5-fluorouracil against all tested human cancer cell lines. Flow cytometry analysis demonstrated that treatment of MGC-803 with 3c led to cell cycle arrest at G2/M phase accompanied by an increase in apoptotic cell death after 12 h.

Synthesis and biological evaluation of coumarin–1,2,3-triazole–dithiocarbamate hybrids as potent LSD1 inhibitors

Two series of coumarin–1,2,3-triazole–dithiocarbamate hybrids were designed, synthesized and evaluated for their inhibitory activity towards lysine specific demethylase 1 (LSD1). Compounds 8a, 8d–8f, 8i–8l presented potent activity against lysine specific demethylase 1. Among them, compound 8k showed potent and reversible inhibition against lysine specific demethylase 1 with an IC50 value of 0.39 μM, which was 74-fold more potent than that of tranylcypromine (2-PCPA). Besides, compound 8k displayed excellent selectivity against lysine specific demethylase 1 without inhibition against monoamine oxidases (MAOs) A and B. Further investigation revealed that compound 8k was active at both recombinant and cell levels by upregulating the expression of H3K4me1, H3K4me2 and H3K9me2.

Design and synthesis of novel D-ring fused steroidal heterocycles

Using dehydroepiandrosterone as the starting material, we have synthesized a series of steroid analogs possessing a D-ring fused with heterocycles which are pyridine, imidazo [2,1-b]thiazoles or substituted thiazole imines. All the final structures are first reported and identified by NMR and MS spectroscopys, the yields of these products are moderate to good and the reaction conditions are mild. The cytotoxicity of the synthesized compounds against EC-109(human esophageal carcinoma), EC-9706(human esophageal carcinoma), MGC-803(human gastric carcinoma) were investigated.

A novel [1,2,4] triazolo [1,5-a] pyrimidine-based phenyl-linked steroid dimer: synthesis and its cytotoxic activity.

A novel [1,2,4] triazolo [1,5-a] pyrimidine-based phenyl-linked steroid dimer was designed, synthesized and evaluated for its cytotoxic activity against five human cancer cell lines and the cytotoxicity against human normal liver cell L-02. Compound 3 showed excellent cytotoxic activity and good selectivity between cancer and normal cells. Further mechanistic studies revealed that treatment of EC109 cells with compound 3 caused an obvious G2/M arrest in a concentration- and time-dependent manner and induced apoptosis probably through the mitochondrial pathway accompanied with the decrease of mitochondrial membrane potential, activations of caspase-9/-3, cleavage of MDM2 as well as up-regulation of the expressions of p53 and Bax.

Facile synthesis of novel D-ring modified steroidal dienamides via rearrangement of 2H-pyrans

A simple and practical method for synthesis of the D-ring modified steroidal dienamides (4a-k) from the steroidal α,α-dicyanoalkene 3 and aldehydes via vinylogous aldol reaction was first reported. By using NaOAc as a base, the desired products were obtained in moderate to good yields in ethanol under mild conditions. All the synthesized steroidal dienamides are new and are currently being evaluated for their biological activities.

Efficient construction of novel D-ring modified steroidal dienamides and their cytotoxic activities

Two series of steroidal dienamides 4a-q and 5a-f were designed, synthesized and evaluated for cytotoxic activities against five human cancer cell lines (MGC-803, EC109, PC-3, SMMC-7721 and MCF-7). The protocol developed efficiently achieved the construction of carbon-carbon double bond and selective conversion of nitrile group into carboxamide in one-pot procedure. Besides, compounds 4a-q and 5a-f showed moderate to excellent cytotoxic activities with the IC₅₀ values ranging from 0.1 to 40 μM and most of them were more potent than 5-fluorouracil. Particularly, four compounds 4d, 4e, 4q and 5a showed excellent selectivity against MGC-803 with the IC₅₀ values less than 1 μM. Flow cytometry analysis demonstrated that compound 4c caused the cellular early apoptosis and cell cycle arrest in G2/M phase in a concentration-independent manner.

Synthesis and preliminary biological evaluation of 1,2,3-triazole-Jaspine B hybrids as potential cytotoxic agents

Two series of more available novel 1,2,3-triazole-Jaspine B hybrids were efficiently synthesized employing click chemistry approach and evaluated for their cytotoxic activities against three human cancer cell lines (EC-9706, MGC-803 and MCF-7). Among them, compound 14h showed excellent inhibition against MCF-7 (IC50 = 1.93 μM) and was more potent than 5-Fu and Jaspine B against all three cancer cell lines. Further investigation of apoptosis assay and cell cycle analysis demonstrated that compound 14h caused cellular early and late apoptosis and arrested the cell cycle at G2/M phase in a concentration- and time-independent manner. This was the first report about the synthesis and in vitro cytotoxic evaluation of 1,2,3-triazole-Jaspine B hybrids.

Stereoselective synthesis of novel antiproliferative steroidal (E, E) dienamides through a cascade aldol/cyclization process

The stereoselective and metal-free protocol involving a cascade aldol/cyclization process for the synthesis of steroidal (E, E) dienamides from steroidal α, α-dicyanoalkene was reported. This protocol efficiently achieved the construction of C=C bond and selective conversion of cyano group into carboxamide in one-pot procedure under mild condition. Further biological evaluation showed that some of these compounds had moderate to excellent cytotoxic activities against all the tested cancer cell lines and were more potent than well-known drug 5-fluorouracil. Particularly, compound 3c represented excellent inhibitory effect against MCF-7 (IC50=0.76 μM), which was about 10-fold more potent than 5-fluorouracil.

Synthesis and biological evaluation of dehydroepiandrosterone-fused thiazole, imidazo[2,1-b]thiazole, pyridine steroidal analogues

A series of steroidal[17,16-d]thiazole, steroidal[1,2-b]pyridine and steroidal[17,16-d]thiazole[2,1-b]imidazo products were synthesized through a convenient and productive method. Anti-proliferation activity against EC109 (human esophageal carcinoma), EC9706 (human esophageal carcinoma) and MGC-803 (human gastric carcinoma) cell lines was examined in vitro. Among the screened compounds, several highly potential compounds were located.

Design, synthesis and antibacterial evaluation of novel AHL analogues.

Two series of novel AHL analogues were designed, synthesized and evaluated for antibacterial activity under cell membrane conditions in vitro. Analogues 4a-c and 4g-m presented potent activity against Gram-positive bacteria. Especially the analogue 4l exerted the most potent inhibition against Bacillus subtilis with MIC50 value of 1.443μg/ml. To our surprise, analogues 6a-c and 6g showed weak inhibition against Gram-negative bacteria with MIC50 values ranging from 17.589 to 67.840μg/ml. This was the first report about synthesis and antibacterial evaluation in vitro of AHL analogues containing dithioester linkage.