1,5-Benzodiazepines XIV. Synthesis of new substituted 9H-bis-[1,2,4]triazolo[4,3-a:3',4'-d] [1,5]benzodiazepines and relate compounds endowed with in vitro cytotoxic properties

A series of 11 new 9H-bis-[1,2,4]triazolo[4,3-a:3',4'-d] [1,5]benzodiazepine derivatives 8e-o was synthesized. Ten of these compounds (8e-m,o), along with four analogues (8a-d) (previously synthesized by us) were tested in vitro in order to evaluate their cytotoxic and anti-HIV-1 properties. In this connection other six original compounds, i.e., five 9-substituted compounds prepared starting from the 6,12-diphenylderivative 8c (compounds 10, 11, 12, 13a,b) and the bis-triazolone derivative 14, were synthesized and tested for the same purpose. While none of the 20 compounds tested exhibited any appreciable anti-HIV-1 activity, some of them exhibited interesting cytotoxic properties, the best results being shown by compounds 8c,d,k and 11 (CC(50) range=3-12 microM). Therefore, these four compounds were further evaluated for their antiproliferative activity against a panel of human tumor cell lines; actually, compounds 8d, 8k and 11 showed antiproliferative properties against either or both leukemia- and lymphoma-derived cell lines in the low micromolar range.     

Comparison of some 3-(substituted-benzylidene)-1, 3-dihydro-indolin derivatives as ligands of tyrosine kinase based on binding mode studies and biological assay

A series of 3-(substituted-benylidene)-1, 3-dihydro- indolin-2-one, 3-(substituted-benylidene)-1, 3-dihydro- indolin-2-thione and 2, 2'-dithiobis 3-(substituted-benylidene)-1, 3-dihydro-indole derivatives was investigated as inhibitor of p60c-Src tyrosine kinase by performing receptor docking studies and inhibitory activity toward tyrosine phosphorylation. Some compounds were shown to be docked at the site, where the selective inhibitor PP1 [1-tert-Butyl-3-p-tolyl-1H-pyrazolo[3,4-d]pyrimidine-4-yl-amine] was embedded at the enzyme active site. Evaluation of all compounds for the interactions with the parameters of lowest binding energy levels, capability of hydrogen bond formations and superimposibility on enzyme active site by docking studies, it can be assumed that 3-(substituted- benzylidene)-1, 3-dihydro-indolin-2-one and thione derivatives have better interaction with enzyme active site then 2, 2'-dithiobis 3-(substituted-benzylidene)-1, 3-dihydro indole derivatives. The test results for the inhibitory activity against tyrosine kinase by Elisa method revealed that 3-(substituted-benylidene)-1, 3-dihydro- indolin-2-thione derivatives have more activity then 3-(substituted-benylidene)-1, 3-dihydro- indolin-2-one derivatives.     

1-Methyl-3H-pyrazolo[1,2-a]benzo[1,2,3,4]tetrazin-3-ones. Design, synthesis, and biological activity of new antitumor agents

1-Methylpyrazolo[1,2-a]benzo[1,2,3,4]tetrazin-3-ones 4, synthesized in good to excellent yields, were designed as novel alkylating agents because of their peculiar chemical behavior. All derivatives showed antiproliferative activity against more than 50 types of tumor cell lines with GI(50) reaching sub-micromolar values. SAR studies revealed that the presence of a chlorine atom is well-tolerated in both positions 8 and 9, whereas in the case of the methyl group, switching from the 8 to the 9 position gives rise to the most active compound of the series, 4g, either for the number of cell lines inhibited and for selectivity against leukaemia and renal cancer subpanels. COMPARE and 3D-MIND computations indicate, for compounds 4, an activity profile analogous to rifamycins and cytidine analogues.     

Synthesis and antimicrobial activity of new 2-[p-substituted-benzyl]-5-[substituted-carbonylamino]benzoxazoles

A series of 23 new 2-[p-substituted-benzyl]-5-[p-substituted-phenyl/benzyl-carbonylamino]benzoxazole derivatives has been synthesized by reacting 5-amino-2-[p-substituted-benzyl]benzoxazoles with the appropriate carboxylic acid chlorides. The structures of the synthesized compounds were confirmed by IR and (1)H-NMR spectral data. Antimicrobial activities of the compounds were investigated using the twofold serial dilution technique against two gram-positive and two gram-negative bacteria and three Candida species in comparison with standard drugs. Microbiological results indicated that the newly synthesized 2-[p-substituted-benzyl]-5-[p-substituted-phenyl/benzyl-carbonylamino]benzoxazole derivatives (3-25) possessed a broad spectrum of activity, showing MIC values of 6.25-200 microg/mL against the gram-positive and gram-negative microorganisms tested. Moreover, they showed significant antifungal activity with MIC values of 3.12-100 microg/mL against the Candida species tested. Especially, with a MIC value of 3.12 microg/mL, 2-benzyl-5-[p-bromobenzyl-carbonylamino]benzoxazole 9 displayed the same activity against C. glabrata as the standard drug myconazol.     

Synthesis and antiproliferative activity in vitro of new derivatives of 3-aminopyrazolo[3,4-b]pyridine. Part 1. Reaction of 3-aminopyrazolo[3,4-b]pyridine with 1,3-, 1,4-diketones and alpha,beta-unsaturated ketones

The synthesis of several new pyrazolo[3,4-b]pyridine, pyrido[2',3':3,4]-pyrazolo[1,5-a]pyrimidine and imidazo[1',2':1,5]pyrazolo[3,4-b]pyridine derivatives is described. The obtained compounds were tested for their antiproliferative activity in vitro. One of them, 4-phenyl-2-(3,4,5-trimethoxy-beta-styrylo)pyrido- [2',3':3,4]pyrazolo[1,5-a]pyrimidine (9), revealed cytotoxic properties against the cells of all three human cancer cell lines applied. Another one, 2,4-dimethyl-pyrido[2',3':3,4]pyrazolo[1,5-a]-pyrimidine (2), revealed weak cytotoxic activity only against the cells of human bladder cancer cell line HCV29T. All other compounds tested did not reveal any cytotoxic activity.     

5H-哒嗪并[4,5-b]吲哚类新化合物的合成及 抗肿瘤细胞增殖活性

目的 设计并合成5H-哒嗪并[4,5-b]吲哚类化合物,评价其体外抗肿瘤细胞增殖活性。方法 以7-溴-1-氯-8-(3-氯丙氧基)-5-环丙基-5H-哒嗪并[4,5-b]吲哚为起始原料,经取代、醚化、Mannich 反应、选择性氧化共3步或4步反应合成目标化合物;以吉非替尼(gefitinib)为阳性对照药,采用 MTT 法测定了目标化合物对肿瘤细胞株 Bel-7402 和 HT-1080 的抗增殖活性。结果与结论 合成了13 个化合物,其中12 个是未见文献报道的新化合物,其结构经¹H-NMR、MS 谱确证;8个化合物显示出较好的抗肿瘤细胞增殖活性,其中,化合物4a和5a抗增殖活性突出,分别为吉非替尼的3倍和4倍。     

Synthesis and biological evaluation of novel benzo[c]acridine‐diones as potential anticancer agents and tubulin polymerization inhibitors

A new series of novel benzo[c]acridine‐diones possessing pharmacophoric elements of antitubulins with central dihydropyridine bridge were designed and synthesized as potential anticancer agents and tubulin polymerization inhibitors. The cytotoxic activity of the synthesized compounds was evaluated against eight cancer cell lines including MCF‐7, A2780, HeLa, HepG2, DU145, A549, PC3, and LNCAP cancer cells and normal cells human umbilical vein endothelial cell (HUVEC) through 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyl tetrazolium bromide (MTT) assay, wherein β‐lapachone and combretastatin A‐4 were used as positive controls. Some of our compounds ( 4c and 4g ) showed significant cytotoxic activity on cancer cells with IC₅₀ values in the range of 5.23–24.32 μM. None of the synthesized compounds showed significant cytotoxicity on normal HUVEC cells. Among all investigated derivatives, compound 4g showed promising greater antiproliferative activity against all tested cancer cells with the highest sensitivity observed for the PC3 cell line. Results from the flow cytometry analysis of PC3 and MCF‐7 cancer cells treated with 4g showed an induced cell‐cycle arrest at G2/M, and therefore induced apoptosis which occurred at low concentration of test compound, whereas annexin V‐FITC/propidium iodide staining assay in the aforementioned cancer cell lines treated with 4g showed that 4g can cause necrosis in PC3 and MCF‐7 cancer cells at higher concentration. Compound 4g proved to be an inhibitor of tubulin polymerization in a mode similar to that of colchicine and in a dose‐dependent manner. Molecular docking studies of 4g into the colchicine‐binding site of tubulin exhibited a possible mode of interaction between this compound and tubulin.     

Pyrido[2,1-f]purine-2,4-dione derivatives as a novel class of highly potent human A(3) adenosine receptor antagonists

1H,3H-Pyrido[2,1-f]purine-2,4-diones, which can be described as fused xanthine structures, have been synthesized by a novel synthetic procedure, and their affinities for the human adenosine A(1), A(2A), and A(3) receptors have been evaluated in radioligand binding studies. The synthetic procedure employed was developed in our laboratory and involved a two-step one-pot reaction that consists of the treatment of 6-aminouracil derivatives with N-bromosuccinimide to generate a 5,5-dibromo-6-imino intermediate that reacts "in situ" with pyridine, 4-methoxypyridine, 4-tert-butylpyridine, or 4-phenylpyridine to afford the corresponding 1H,3H-pyrido[2,1-f]purine-2,4-diones (2-5). Functionalization at the N(3) position in compounds 2-5 was performed by reaction with DBU and different alkyl, alkenyl, alkynyl, or benzyl halides. Binding studies at human adenosine A(1), A(2A), and A(3) receptors revealed significant antagonist effects in the low nanomolar range, in particular against the A(3) receptor. Thus, the 1-benzyl-3-propyl-1H,3H-pyrido[2,1-f]purine-2,4-dione derivative 6, which can be considered a lead compound in this series, exhibited a K(i) value of 4.0 +/- 0.3 nM against the hA(3) receptor. Because xanthine derivatives have traditionally been considered poor A(3) antagonists, the described pyrido[2,1-f]purine-2,4-dione derivatives represent a new family of adenosine receptor antagonists which deserves further exploration.     

2,3-Diaryl-3H-imidazo[4,5-b]pyridine derivatives as potential anticancer and anti-inflammatory agents

In this study we examined the suitability of the 3H-imidazo[4,5-b]pyridine ring system in developing novel anticancer and anti-inflammatory agents incorporating a diaryl pharmacophore. Eight 2,3-diaryl-3H-imidazo[4,5-b]pyridine derivatives retrieved from our in-house database were evaluated for their cytotoxic activity against nine cancer cell lines. The results indicated that the compounds showed moderate cytotoxic activity against MCF-7, MDA-MB-468, K562 and SaOS2 cells, with K562 being the most sensitive among the four cancer cell lines. The eight 2,3-diaryl-3H-imidazo[4,5-b]pyridine derivatives were also evaluated for their COX-1 and COX-2 inhibitory activity in vitro. The results showed that compound 3f exhibited 2-fold selectivity with IC₅₀ values of 9.2 and 21.8 µmol/L against COX-2 and COX-1, respectively. Molecular docking studies on the most active compound 3f revealed a binding mode similar to that of celecoxib in the active site of the COX-2 enzyme.     

Synthesis and antiproliferative activity in vitro of new 3-substituted aminopyrazolo[3,4-b]pyridines

The synthesis of several new 3-substituted aminopyrazolo[3,4-b]pyridines is described. The obtained compounds were tested for their antiproliferative activity in vitro. Two of them: 3-chloroacetylaminopyrazolo[3,4-b]pyridine [II] and 3-(2-bromopropionyl-amino)pyrazolo[3.4-b]pyridine [III] revealed cytotoxic activity against the cells of 5 human tumor cell lines applied. Their ID50 values were in the range of the international activity criterion for synthetic agents (4 microg/ml). The structures of the products II-XVII were established on the basis of elemental analysis and spectral data (IR, 1H NMR and MS).     

Quinoxaline chemistry. Part 16. 4-substituted anilino and 4-substituted phenoxymethyl pyrrolo[1,2-a]quinoxalines and N-[4-(pyrrolo[1,2-a]quinoxalin-4-yl)amino and hydroxymethyl]benzoyl glutamates. Synthesis and evaluation of in vitro biological activity

Twenty eight pyrrolo[1,2-a]quinoxalines bearing at position 4 various substituents related to the moieties present in classical and non classical antifolic agents were prepared and evaluated in vitro for antiproliferative activity. In an in vitro screening performed at NCI, several compounds emerged as potent antiproliferative agents at concentrations ranging between 10 and 100 microM. Interestingly, some of these compounds proved active also against bovine and murine DHFR (Farmaco 53 (1998) 480). More recently, a compound of classical antifolate type has been reported to be a potent inhibitor of hDHFR in vitro (Farmaco 58 (2003) 51). We then synthesized new derivatives that, in our hands, were endowed with in vitro antiproliferative activities as low as 3.4 microM against a panel of cell lines derived from hematological and solid tumours. In addition, a complete screening of cytotoxicity, antiretroviral HIV-1 and antimicrobial activity has been carried out.     

1,4-二氢噻吩并[3',2':5,6]噻喃并[4,3-c]吡唑-3-羧酸衍生物的合成及抗癌活性研究(英文)

本文以2-巯基噻吩为原料,经6步反应合成了5个1,4-二氢噻吩并[3',2':5,6]噻喃并[4,3-c]吡唑-3-羧酸衍生物,并采用人乳腺癌细胞MCF-7对目标化合物的抗肿瘤活性进行初步评价。所合成化合物在100μM浓度下均有一定的抑制MCF-7活性。     

Synthesis and Biological Evaluation of a Series of Substituted Pyrazolo[3,4-d]-1,2,3-triazoles and Pyrazolo[3,4-d]oxazoles

In view of the biological relevance of triazole-based heterocyclic structures as antifungal, antiviral, and antitumor agents, we have synthesized a series of substituted pyrazolo[3,4-d]-1,2,3-triazoles ( 2e–h, 2j, 4b ) which we evaluated for their cytostatic and antiviral (HIV-1 included) activity and for their capability to inhibit the multiplication of various human pathogenic fungi and bacteria. Moreover, the biological activities of a few compounds, namely pyrazolo[3,4-d]oxazoles ( 3a–e ) and pyrazolo[3,4-d]-1,2,3-triazoles ( 2a–d, 4a, 5 ), previously obtained by us but not investigated for their biological activity, were also studied. Only compounds 3a–e were endowed with a significative antiproliferative activity on the human lymphoblastoid cell line MT-4 cells. All pyrazole derivatives proved ineffective in protecting cell cultures against the HIV-1-induced cytopathogenicity, and none of the compounds was active against the bacteria and fungi tested.     

Preparation and biodistribution of 1-[2-(3-[125I]iodo-4-aminophenyl)ethyl]-4-[3-(trifluoromethyl) phenyl]piperazine and 1-[2-(3-[125I]iodo-4-azidophenyl)ethyl]-4-[3-(trifluoromethyl)phenyl] piperazine

The iodinated analogue of 1-[2-(4-aminophenyl)ethyl]-4-[3-(trifluoromethyl)phenyl]piperazine (PAPP), IPAPP (4), and the corresponding azido compound azido-IPAPP (5) were synthesized. The corresponding no-carrier-added 125I (T1/2 = 60 days, 35-60 keV) labeled compounds were also prepared. High specific binding was observed from in vitro binding studies using rat brain tissue preparation; Ki = 20 and 17.5 nM against [3H]-5-HT. In vivo biodistribution studies in rats showed that azido-[125I]IPAPP passed through intact blood-brain barrier and localized in the brain. Ex vivo autoradiography of rat brain sections exhibited a diffuse uptake pattern, which may be due to specific and nonspecific binding. The results indicate that IPAPP and azido-IPAPP may not be suitable to image the serotonin receptor in the brain.     

Synthesis and biological activity of new heterocyclic structures: [1,3]thiazino[2,3-i]purine, thiazolo[3,2-c] [1,2,3]triazolo[4,5-e]pyrimidine and [1,2,3]triazolo [4', 5': 4,5] pyrimido[6,1-b][1,3]thiazine.

Some derivatives of thiazolo[3,2-c]pyrimidine, pyrimido[6,1-b][1,3]thiazine, thiazolo[2,3-i]purine, [1,3]thiazino[2,3-i]purine, thiazolo[3,2-c][1,2,3]triazolo[4,5-e]pyrimidine and [1,2,3]triazolo[4',5':4,5]pyrimido[6,1-b][1,3]thiazine were prepared. The compounds were tested for antimicrobial and antimycotic activity on a number of strains, namely, Escherichia coli, Proteus vulgaris, P. mirabilis, Pseudomonas aeruginosa, Salmonella sp., Staphylococcus aureus, Streptococcus faecalis, Bacillus subtilis, Sarcina lutea, Candida albicans, Aspergillus sp., and for antiviral activity on Herpes simplex virus, Type 1 (HSV-1), Vesicular stomatitis virus (VSV) and Coxsackievirus B5 (CoxB5). The compounds proved to be devoid of activity against viruses, mycetes and gram-negative bacteria, while some of them exhibited a modest activity against gram-positive bacterial strains.     

2-取代-4-氨基噻吩并[3,2-d]嘧啶类化合物的合成及抗增殖活性

目的设计并合成2-取代-4-氨基噻吩并[3,2-d]嘧啶类化合物,评价其体外抗增殖活性。方法以3-氨基-2-噻吩甲酸甲酯为起始原料,经6步反应合成目标化合物;以CP-31398为阳性对照药,采用MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]法测定了目标化合物对肿瘤细胞株H-460和HT-29的抗增殖活性。结果与结论合成16个未见文献报道的化合物,其结构经1H-NMR、MS确证;5个化合物显示较好的抗增殖活性,其中,化合物8n活性突出,为CP-31398的4-5倍。