Sheng-Li Cao

Synthesis and antiproliferative activity of 4-substituted-piperazine-1-carbodithioate derivatives of 2,4-diaminoquinazoline

A novel series of 4-substituted-piperazine-1-carbodithioate derivatives of 2,4-diaminoquinazoline were synthesized and tested for their antiproliferative activities against five human cancer cell lines including A549 (lung cancer), MCF-7 (breast adenocarcinoma), HeLa (cervical carcinoma), HT29 and HCT-116 (colorectal cancer). Most of the synthesized compounds showed broad spectrum antiproliferative activity (IC50 1.47-11.83 μM), of which 8f, 8m and 8q were the most active members with IC50 values in the range of 1.58-2.27, 1.84-3.27 and 1.47-4.68 μM against five cancer cell lines examined, respectively. Further investigations revealed that compounds 8f, 8m and 8q exhibited weak inhibition against dihydrofolate reductase and no activity against thymidylate synthase, while induced DNA damage and activated the G2/M checkpoint in HCT-116 cells.

Synthesis and cytotoxic activity of N-((2-methyl-4(3H)-quinazolinon-6-yl)methyl) dithiocarbamates

A series of N-((2-methyl-4(3H)-quinazolinon-6-yl)methyl)dithiocarbamates 5a-w were synthesized and evaluated for their cytotoxic activity against five human cancer cell lines. We found that compound 5k inhibited proliferation of A549, MCF-7, HeLa, HT29 and HCT-116 cells with IC(50) values of 5.44, 7.15, 12.16, 10.35 and 11.44 microM, respectively. Compound 5i was the most potent with an IC(50) value of 3.65 microM against proliferation of MCF-7 cells, while 5n was the most potent with an IC(50) value of 5.09 microM against proliferation of A549 cells. Cell cycle analysis showed that both 5i and 5k arrested A549 cells at S and G2/M phases, suggesting that these compounds act through mechanisms different from 5-fluorouracil, which arrests cells at S phase only.

Synthesis and antiproliferative evaluation of piperazine-1-carbothiohydrazide derivatives of indolin-2-one

By varying the substituents (R(1)) at the indolin-2-one scaffold, a series of indolin-2-one derivatives bearing 4-phenylpiperazine-1-carbothiohydrazide moiety at the C3-position were synthesized and evaluated for their antiproliferative activity against three human cancer cell lines. We further selected the 5-chloroindolin-2-one moiety for the extension to another series of compounds by varying the substituents (R(2)) at the phenyl group connected with the piperazine ring. Among all the compounds synthesized, 6d and 6l were most potent with IC50 values of 3.59 and 5.58 μM, respectively against A549 lung cancer cells, while 5f and 6l possessed IC50 values of 3.49 and 4.57 μM, respectively against HCT-116 colon cancer cells which were comparable to that of Sunitinib, an indolin-2-one derivative in cancer therapy.

Synthesis and cytotoxicity screening of piperazine-1-carbodithioate derivatives of 2-substituted quinazolin-4(3H)-ones.

A new series of piperazine‐1‐carbodithioate derivatives of 2‐substituted quinazolin‐4(3H)‐ones were synthesized via a five‐steps procedure starting from 2‐amino‐5‐methylbenzoic acid. The cytotoxicity of the resulting compounds against A‐549 (human lung cancer), HCT‐8 (human colon cancer), HepG2 (human liver cancer), and K562 (human myelogenous leukaemia) cell lines was determined by the MTT assay. Preliminary screening results of these compounds are reported.

Synthesis and antitumor activity evaluation of quinazoline derivatives bearing piperazine-1-carbodithioate moiety at C4-position

A series of quinazoline derivatives bearing piperazine-1-carbodithioate moiety at the C4-position were synthesized using piperidine and 1-bromo-3-chloropropane as starting materials via eight steps. Final compounds 8a-q and 9a-i were evaluated for their antiproliferative activity against human lung cancer A549, breast adenocarcinoma MCF-7, and colorectal cancer HCT-116 cell lines. The results showed that fourteen of twenty-six final compounds inhibited the proliferation of three cancer cell lines with IC50 values less than 10μM. When treated with a representative compound 8n, HCT-116 cells were arrested at G0/G1 phase of the cell cycle. This provided a clue to further investigation of the mechanism of action.

Synthesis of 3-Aryl-4(3H)-quinazolinones from Anthranilic Acids and Triethyl Orthoformate

Abstract A one-step, convenient approach to the synthesis of 3-aryl-4(3H)-quinazolinones by the reaction of anthranilic acid with triethyl orthoformate in the presence of a catalytic amount of concentrated sulfuric acid has been developed. The possible reaction pathway was proposed.

Synthesis of 1-Substituted 4(1H)-Quinazolinones Under Solvent-Free Conditions

Abstract Heating a mixture of 2-(N-alkylamino)benzoic acids, triethyl orthoformate, and ammonium acetate under solvent-free conditions generated 1-substituted 4(1H)-quinazolinones in 73−99% yields. Moreover, a possible reaction pathway was proposed. GRAPHICAL ABSTRACT

Synthesis and Cytotoxic Evaluation of Quinazolin-4(3H)-one Derivatives Bearing Thiocarbamate, Thiourea or N-Methyldithiocarbamate Side Chains

We have previously found that the dithiocarbamate derivatives of quinazolin-4(3H)-one could act as cytotoxic agents against a panel of human tumor cell lines. To investigate the contribution of dithiocarbamate moiety to the cytotoxic activity, three series of novel quinazolin-4(3H)-one derivatives bearing thiocarbamate, thiourea or Nmethyldithiocarbamate side chains were synthesized and tested for their cytotoxic activity against human cancer cell lines A549, MCF-7, HeLa, HT29 and HCT-116 by MTT assay. The results showed that transformation of the dithiocarbamate moiety in lead compound I to thiocarbamate or thiourea led to a decrease or loss of cytotoxic activity. Some N-alkylated analogs of lead compound II preferentially inhibited the proliferation of A549 cells, although their potencies were not improved in comparison with the unalkylated counterparts. The structure-activity relationship obtained in this research will be beneficial for further synthesis and discovery of effective cytotoxic agents.

2-(5-Fluoro-2,3-dioxoindolin-1-yl)ethyl 4-methyl­piperazine-1-carbodithio­ate

In the title compound, C16H18FN3O2S2, the methylpiperazine ring adopts a chair conformation, while the (2,3-dioxoindolin-1-yl)ethyl unit is linked to one of the N atoms of the piperazine ring via the carbodithioate group. In the crystal, each molecule is linked to its neighbors within the (03) plane through weak C—H(methylene)⋯O, C—H(aryl)⋯O and C—H(methylene)⋯S interactions. Perpendicular to this plane molecules are connected through intermolecular short N⋯π(pyrrole ring) contacts [N⋯C centroid = 3.232 (2) Å], another set of C—H(methylene)⋯O interactions and through short contacts between carbodithioate S atoms and the pyrrole rings [C⋯centroid = 3.695 (3), S⋯centroid = 3.403 (2) Å].

5-Chloro-1-(4-meth-oxy-benz-yl)indoline-2,3-dione.

In the title compound, C16H12ClNO3, an arm-like 4-methoxybenzene links to 5-chloroindoline-2,3-dione through a methylene group, with a dihedral angle between the mean planes of the benzene ring and the indole moiety of 88.44 (8)°. In the crystal, weak intermolecular C—H⋯O and π–π stacking interactions [centroid–centroid distance = 3.383 (3) Å] link the molecules together to form a three-dimensional framework.