Biological mechanisms of action of novel C-10 non-acetal trioxane dimers in prostate cancer cell lines

The mechanisms of action of three C-10 non-acetal trioxane dimers (TDs) were examined in human (LNCaP) and mouse (TRAMP-C1A and -C2H) prostate cancer cell lines. 1 (AJM3/23), 2 (GHP-TM-III-07w), and 3 (GHP-KB-06) inhibited cell growth with 3 being the most potent in C1A (GI50 = 18.0 nM), C2H (GI50 = 17.0 nM), and LNCaP (GI50 = 17.9 nM) cells. In comparison to a standard cytotoxic agent such as doxorubicin (GI50 = 45.3 nM), 3 (GI50 = 17.9 nM) inhibited LNCaP cell growth more potently. TDs induced G0/G1 cell cycle arrest in LNCaP cells and decreased cells in the S phase. These changes correlated with modulation of G1 phase cell cycle proteins including decreased cyclin D1, cyclin E, and cdk2 and increased p21waf1 and p27Kip1. TDs also promoted apoptosis in LNCaP cells with increased expression of proapoptotic bax. These results demonstrate that TDs are potentially useful agents that warrant further preclinical development for treatment of prostate cancer.     

Antitumor activity of novel deoxoartemisinin monomers,dimers, and trimer

The first primary amines 9 and bromoalkyl analogues 7 of deoxoartemisinin with nonacetal functionality at C-12 are prepared as versatile intermediates for the synthesis of various derivatives. Eight C-12 nonacetal type dimers and one trimer of deoxoartemisinin were prepared using novel chemistry. Dimers, particularly 12a, 18a,b, and trimer 17, were especially potent and selective at inhibiting the growth of certain human cancer cell lines and were comparable to that of clinically used anticancer drugs. The linker with one amide- or one sulfur-centered two ethylene groups of the dimers is essential for high anticancer activity. Trimer 17 shows very potent activity against most of the human cancer cell lines tested.     

Antimalarial, antiproliferative, and antitumor activities of artemisinin-derived, chemically robust, trioxane dimers.

Nine C-10 non-acetal derivatives of the natural trioxane artemisinin (1) were prepared as dimers using some novel chemistry. As designed, each dimer was stable chemically. C-10 Olefinic dimers 7 and C-10 saturated dimers 8-13 all showed good to excellent antimalarial and antiproliferative activities in vitro. Dimers 8, 10, and 12 were especially potent and selective at inhibiting growth of some human cancer cell lines in the NCI in vitro 60-cell line assay.     

14 beta-(2-bromoacetamido)morphine and 14 beta-(2-bromoacetamido)morphinone

14 beta-(2-Bromoacetamido)morphine (6) and 14 beta-(2-bromoacetamido)morphinone (9) were prepared preferably from the adduct of thebaine and 1-chloro-1-nitrosocyclohexane, which on reduction in methanol solution gave 14-aminocodeinone (2) and the corresponding ketal (3). When tested in a receptor-binding assay, the IC50 values of 6 and 9 were 15 and 10 nM, respectively. If the incubation time during the assay was increased from 15 to 30 min, irreversible binding of both ligands was observed.     

Synthesis and evaluation of antitumor activity of novel 1,4-Naphthoquinone derivatives (IV)

1,4-Naphthoquinones are widely distributed in nature and many clinically important antitumor drugs containing a quinone moiety, such as anthracyclines, mitoxantrones and saintopin, show excellent anticancer activity. In this study, 2- or 6-substituted 5,8-dimethoxy-1,4-naphthoquinone (DMNQ) and 5,8-dihydroxy-1,4-naphthoquinone (DHNQ) derivatives were synthesized, and their cytotoxic activity against L1210 and P388 cancer cells was examined. Their antitumor activity was also assessed in mice bearing S-180 cells in the peritoneal cavity. In comparison with the DMNQ derivatives, the DHNQ derivatives exhibited more potent bioactivities than the DMNQ derivatives against both L1210 and P388 cells in vitro and S-180 cells in vivo. The ED50 values of the DHNQ derivatives against P388 cells were in the range of 0.18-1.81 microg/mL whereas those of the DMNQ derivatives were in the range of 0.26-40.41 microg/mL. The T/C (%) values of the DHNQ derivatives, 8, 17, 18, 19, and 20, were found to be comparable to or even better than that of adriamycin. It was also observed that the 2-substituted derivatives (8, 19, 20) showed better antitumor activity than the 6-substituted derivatives (7, 17, 18) in the mice bearing S-180 cells in the peritoneal cavity.     

Synthesis and biological evaluation of novel (thio)urea derivatives as potential antitumor agents

A series of novel (thio)ureas containing the pyrimidinyl group was designed and synthesized. Their in-vitro antitumor activity against different human tumor cells was examined. Some of the compounds showed potential antitumor activity, which provided some hints for further studies on structure modification.     

Design,synthesis, and evaluation of antitumor activity of novel C-6 sulfhydryl-substituted and 20-substituted derivatives of celastrol

Celastrol has been identified as a potential candidate for anticancer drug development. In this study, 28 novel celastrol derivatives with C-6 sulfhydryl substitution and 20-substitution were designed and synthesized, and their antiproliferative activity against human cancer cells and non-malignant human cells was evaluated, with cisplatin and celastrol being used as controls. The results showed that most of the derivatives had enhanced in vitro anticancer activity compared to the parent compound celastrol. Specifically, derivative 2f demonstrated the most potent inhibitory potential and selectivity against HOS with an IC₅₀ value of 0.82 μM. Our study provides new insights into the structure–activity relationship of celastrol and suggests that compound 2f may be a promising drug candidate for the treatment of osteosarcoma.     

2-(1-取代哌啶-4-氨基)喹唑啉类化合物的合成及抗肿瘤活性研究(英文)

本文合成了一系列新结构的2-(1-取代哌啶-4-氨基)喹唑啉衍生物,采用MTT法评价了化合物对5种肿瘤细胞系的抑制活性。研究结果表明:在哌啶环上引入小体积的疏水性烷基取代基,得到的化合物4j～4l、5a、5b和5d具有较强的细胞毒活性,IC50值在微摩尔水平。在小鼠移植瘤模型实验中,化合物4l表现出了较强的体内抗肿瘤活性,在200 mg.kg1的剂量下,对H22肿瘤生长抑制率为72.9%,对Lewis肺癌的抑制率达到了80%。     

Synthesis and evaluation of novel polyaminocarboxylate-based antitumor agents

Iron depletion, using iron chelators targeting transferrin receptor (TfR) and ribonucleotide reductase (RR), is proven to be effective in the treatment of cancer. We synthesized and evaluated novel polyaminocarboxylate-based chelators NETA, NE3TA, and NE3TA-Bn and their bifunctional versions C-NETA, C-NE3TA, and N-NE3TA for use in iron depletion tumor therapy. The cytotoxic activities of the novel polyaminocarboxylates were evaluated in the HeLa and HT29 colon cancer cell lines and compared to the clinically available iron depletion agent DFO and the frequently explored polyaminocarboxylate DTPA. All new chelators except C-NETA displayed enhanced cytotoxicities in both HeLa and HT29 cancer cells compared to DFO and DTPA. Incorporation of the nitro functional unit for conjugation to a targeting moiety into the two potent non-functionalized chelators NE3TA and NE3TA-Bn (C-NE3TA and N-NE3TA) was well-tolerated and resulted in a minimal decrease in cytotoxicity. Cellular uptake of C-NE3TA, examined using a confocal microscope, indicates that the chelator is taken up into HT29 cancer cells.     

Synthesis and antitumor evaluation of some novel pyrrolizine derivatives

Novel series of pyrrolizines (7, 9a–d, 10a–d, 11a, b, 14a–d, 16, 19, 20a, b, 24, 25a, b), pyrimido[5,4-a]pyrrolizines (12a, b, 13, 15a, b, 18, 21a, b, 22, 23a–d) and pyrido[3,2-a]pyrrolizines (17, 26a, b) were synthesized through different reactions. The chemical structures of all the synthesized pyrrolizine derivatives were determined by spectral and elemental analyses. Antitumor activity evaluation of all the prepared compounds was carried out using NR assay method against breast cancer cell line (MCF-7). The novel pyrrolizine scaffold 7 and all its prepared derivatives showed high antitumor activity comparable to that of doxorubicin.     

Cyclisierungen von N-(2-Phenylethyl)-2-(2-hydroxyethyl)-benzamiden

Cyclisation of N-(2-Phenylethyl)-2-(2-hydroxyethyl)benzamides The cyclisation of the hydroxyamides 3 according to Bischler-Napieralski proceeds in three ways depending on the substituents at the aromatic rings: The amides 3c and 3d , the phenylethylamine parts (ring A) of which are not activated, close only ring C. The amide 3b , which is activated in ring A but - with regard to nucleophilic attack - deactivated in ring D (lactone part), closes ring B, too, after ring C has been closed. Finally, with 3a activated in ring A only, Bischler-Napieralski cyclisation (formation of ring B) takes place first and intramolecular N-alkylation (formation of ring C) follows.     

Design,synthesis, and evaluation of novel (E)-N'-(3-allyl-2-hydroxy)benzylidene-2-(4-oxoquinazolin-3(4H)-yl)acetohydrazides as antitumor agents

In our continuing search for novel small-molecule anticancer agents, we designed and synthesized a series of novel (E)-N'-(3-allyl-2-hydroxy)benzylidene-2-(4-oxoquinazolin-3(4H)-yl)acetohydrazides ( 5 ), focusing on the modification of substitution in the quinazolin-4(3H)-one moiety. The biological evaluation showed that all 13 designed and synthesized compounds displayed significant cytotoxicity against three human cancer cell lines (SW620, colon cancer; PC-3, prostate cancer; NCI-H23, lung cancer). The most potent compound 5l displayed cytotoxicity up to 213-fold more potent than 5-fluorouracil and 87-fold more potent than PAC-1, the first procaspase-activating compound. Structure–activity relationship analysis revealed that substitution of either electron-withdrawing or electron-releasing groups at positions 6 or 7 on the quinazolin-4(3H)-4-one moiety increased the cytotoxicity of the compounds, but substitution at position 6 seemed to be more favorable. In the caspase activation assay, compound 5l was found to activate the caspase activity by 291% in comparison to PAC-1, which was used as a control. Further docking simulation also revealed that this compound may be a potent allosteric inhibitor of procaspase-3 through chelation of the inhibitory zinc ion. Physicochemical and ADMET calculations for 5l provided useful information of its suitable absorption profile and some toxicological effects that need further optimization to be developed as a promising anticancer agent.     

Synthesis and antitumor evaluation of selected 5,6-disubstituted 1(2)H-indazole-4,7-diones

A series of novel aziridinyl-substituted 1(2)H-indazole-4,7-diones and related 1(2)H-indazole-4,7-diones was synthesized and tested against Ehrlich ascites carcinoma growth in male CF1 mice. Ten of the test compounds, including two aziridinyl-substituted 1(2)H-indazole-4,7-diones, were found to be significantly active (inhibition of tumor growth greater than 80%) in the Ehrlich ascites carcinoma screen. Several structure-activity relationships were indicated for antitumor activity in this screen. An aziridinyl-substituted derivative, 5-aziridinyl-6-chloro-1H-indazole-4,7-dione (8a), also exhibited significant activity against the growth of P-388 lymphocytic leukemia cells in male BDF1 mice (% T/C = 145; % T/C greater than 125 is considered significant).     

Synthesis and antitumor activity evaluation of novel ursolic acid derivatives

Eleven novel ursolic acid (UA) derivatives were designed and synthesized with modification at positions of C-2, C-3, and C-28 of UA. Their structures were confirmed by MS, ¹H NMR, and elemental analysis. Their in vitro cytotoxicities against various cancer cell lines (HeLa, HepG2, and BGC-823) were evaluated by MTT assay. The results indicated that all compounds could inhibit cell proliferation of HeLa, HepG2, and BGC-823 cells. Among them, compounds I₃ and I₄ showed more potent cytotoxicity on these three tumor cells than gefitinib (positive control), worthy to be studied further.     

Synthesis and antitumor activity evaluation of novel oleanolic acid derivatives

Ten novel oleanolic acid (OA) derivatives were synthesized through modifications at positions of A ring and C-28. Inhibitory activities of the oleanolic acid derivatives against SGC7901 and A549 cell lines were evaluated and confirmed by the tetrazolium bromidesalt (MTT) assay. The lab results revealed that all these compounds displayed some antitumor activity against SGC-7901 and A-549 cell lines. Among them, II₄ and II₅ exhibited excellent antitumor activities against SGC7901 cells and A549 cells, compared with gefitinib. Molecular docking studies have shown that compounds II₄ and II₅ produce potent antitumor activities by interacting with C-kit receptor through hydrogen bonds and hydrophobic bonds.     

Synthesis and antitumor activity of novel C-7 paclitaxel ethers: discovery of BMS-184476.

The preparation of C-7 paclitaxel ethers is described. Various substituted ethers were prepared via activation of the corresponding methylthiomethyl ether followed by alcohol addition. Variation of the C-7 ether group as well the 3' side chain position led to the discovery of a novel taxane, BMS-184476 (4), with preclinical antitumor activity superior to paclitaxel.