Wei-Xiao Hu

Synthesis of trans-caffeate analogues and their bioactivities against HIV-1 integrase and cancer cell lines.

Forty caffeate analogues were synthesized via a convenient method starting from vanillin with moderate to good yields. The testing of biological activity of these compounds against HIV-1 integrase indicates that four compounds: bornyl caffeate, bornyl 2-nitrocaffeate, 5-nitrocaffeic acid and 5-nitrocaffeic acid phenethyl ester (5-nitroCAPE) possess a good HIV integrase inhibitory activity, IC(50) 19.9, 26.8, 25.0 and 13.5 microM , respectively. Twelve caffeate analogues were tested by MTT assay on growth of human hepatocellular carcinoma BEL-7404, human breast MCF-7 adenocarcinoma, human lung A549 adenocarcinoma and human gastric cancer BCG823 cell lines, respectively. And the best result is IC(50) 5.5 microM for CAPE against BEL-7404.

Synthesis and anticancer evaluation of α-lipoic acid derivatives

alpha-Lipoic acid derivatives were synthesized and evaluated for their in vitro anticancer activities against NCI-460, HO-8910, KB, BEL-7402, and PC-3 cell lines. The results, for most compounds exhibited dose-dependent inhibitory property and several compounds had good inhibitions at the dose of 100 microg/mL. Compound 17 m was further selected for in vivo evaluation against S180 xenograft in ICR mice, which had 24.7% tumor-weight inhibition through intragastric administration of 200mg/kg of body weight. Moreover, the LD(50) in mice for 17 m through ig exceeded 1000 mg/kg of body weight.

Synthesis and biological evaluation of amide derivatives of diflunisal as potential anti-tumor agents

To discover the new medicinal activity, the structure of diflunisal has been modified. Forty amide derivatives of diflunisal were synthesized starting from diflunisal in three steps. Their inhibition growth rate of human lung cancer cell (A549) and human endometrial adenocarcinoma cell (Ishikawa) in vitro was evaluated. The preliminary assay results showed that compounds 6j, 7o and 8c exhibited good anti-tumor activities and excellent selectivity for the Ishikawa cell, may be potential anti-tumor agents.

Rapid Microwave‐Promoted Catalyst‐ and Solvent‐Free Suzuki‐Type Coupling Reaction

Abstract The catalyst‐ and solvent‐free Suzuki coupling reaction of sodium tetraphenylborate with hypervalent iodonium salts was achieved under microwave irradiation in the absence of a base. A convenient method for formation of carbon–carbon bonds afforded good yields in a short time.

Synthesis, structure analysis, antitumor evaluation and 3D-QSAR studies of 3,6-disubstituted-dihydro-1,2,4,5-tetrazine derivatives.

3,6-Diaryl-dihydro-1,2,4,5-tetrazine derivatives were synthesized and their structures were confirmed by single-crystal X-ray diffraction. Monosubstituted dihydrotetrazines are the 1,4-dihydro structure, but disubstituted dihydrotetrazines are the 1,2-dihydro structure. The results of further research indicated there may be a rearrangement during the synthesis process of disubstituted dihydrotetrazines. Their antitumor activities were evaluated against A-549 and P388 cells in vitro. The results showed several compounds to be endowed with cytotoxicity in the low micromolar range. Two compounds were highly effective against A-549 cell and IC50 values were 0.575 and 2.08 μM, respectively. Three-dimensional quantitative structure-activity relationship (3D-QSAR) studies of comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were carried out on 37 1,2,4,5-tetrazine derivatives with antitumor activity against A-549 cell. Models with good predictive abilities were generated with the cross validated q(2) values for CoMFA and CoMSIA being 0.744 and 0.757, respectively. Conventional r(2) values were 0.978 and 0.988, respectively, the predicted R(2) values were 0.916 and 0.898, respectively. The results provide the tool for guiding the design and synthesis of novel and more potent tetrazine derivatives.

N-Alkylation of Unsymmetrical 1,6-Dihydro-1,2,4,5-tetrazine Under Alkali Condition

Abstract 6-Methyl-3-phenyl-1,6-dihydro-1,2,4,5-tetrazine was stable in alkali solution at room temperature and decomposed gradually to form 1,2-dibenzylidenehydrazine. The plausible mechanism of the reaction is discussed. Because it was stable for a period of time, a convenient and effective method for synthesis of 1-alkyl-1,6-dihydro-1,2,4,5-tetrazines has been developed. The starting 1,6-dihydro-1,2,4,5-tetrazine can be alkylated with alkyl halides in methanol and lithium hydroxide monohydrate as a base at room temperature.

The synthesis and biological evaluation of some caffeic acid amide derivatives: E-2-cyano-(3-substituted phenyl)acrylamides.

A series of caffeic acid amide derivatives 2-cyano-(3-substituted phenyl)acrylamides were synthesized via Knoevenogal condensation of substituted benzaldehydes with cyanoacetamides. The structure of compound 1f was determined as E-isomer by X-ray diffractive analysis. The biological screening tests in vitro showed that compound 1b has obvious inhibitory activities against human gastric carcinoma cell line BGC-823, human nasopharyngeal carcinoma cell line KB and human hepatoma cell line BEL-7402 with IC(50) values of 5.6 microg/mL, 13.1 microg/mL and 12.5 microg/mL, respectively. Some preliminary structure-activity relationships (SAR) were also proposed which may provide a direction for further study.

Method for Regio- and Stereoselective Synthesis of (E)-β,γ-Unsaturated Acids from Aldehydes Under Solvent-Free Conditions

Synthesis of (E)-β,γ-unsaturated acids from aldehydes with malonic acid has been explored under solvent-free conditions. The modified Knoevenagel condensation reaction with N-methyl morpholine (NMM) as catalyst exhibits highly β,γ-regioselectivity and exclusively E-stereoselectivity. A mechanism accounting for both regio- and stereoselectivity has been proposed and preliminarily studied.

(E)-Ethyl 2-cyano-3-(3,4-dihydr­oxy-5-nitro­phen­yl)acrylate

The title compound, C12H10N2O6, was synthesized via a Knoevenagel condensation and crystallized from ethanol. In the crystal, strong classical intermolecular O—H⋯O hydrogen bonds and weak C—H⋯N contacts link the molecules into ribbons extending along [010]. Intramolecular O—H⋯O and C—H⋯N contacts support the planar conformation of the molecules (mean deivation 0.0270 Å).

N-(3,4-Dichloro-phen-yl)thio-urea.

In the title compound, C7H6Cl2N2S, the benzene ring and the mean plane of the thiourea fragment [—N—C(=S)—N] make a dihedral angle of 66.77 (3)°. Intermolecular N—H⋯S and N—H⋯Cl hydrogen bonds link the molecules into a three-dimensional network.