Synthesis of Novel Organogermanium Sesquioxides and Reactivities of 3-(Trichlorogermyl)propanoic Acid

During the past two decades, carboxyethylgermanium sesquioxide Ge-132[O₃(GeCH₂CH₂COOH)₂] and its derivatives have attracted considerable attention because these organogermanium sesquioxides exhibited anticancer activities[1,2]. In 1993, Kurono et al. have synthesized phosphonoethylgermanium sesquioxide[O_3/2GeCH₂CH₂PO(OH)₂], which possesses higher antitumor activity than Ge-132[3]. Encouraged by these promising results, we developed the idea that the incorporation of a germanium residue into α-aminophosphonic acids and their derivatives, which have antibacteria and antitumor activities[4,5], would enhance their antitumor activities to a significant degree, while their toxicity would be reduced at the same time. Therefore, we designed and synthesized a series of novel organogermanium sesquioxides containing α-aminophosphonate groups by the hydrolysis of O,O-diphenyl N-trichlorogermyl propiono-α-aminophosphonates.     

Hydrothermal Synthesis and Crystal Structure of Zinc(Ⅱ) Dinicotinate Complex [Zn(nic)2(H2O)4](nic=nicotinic acid):A Three-dimensional Hydrogen-bond Network

Introduction Nicotinic acid and its transition-metal comple-xes have become increasingly important due to their potential applications as cosmetics or medicines with antitumor, antibacterial and antifungal activities, and the activity in the maintenance of normal glucose metabolism[1-3], etc. A major research effort has been made to generate such materials and to study their biological activity[4-9]. But few of the previous works have directed towards the structure investigation of these metal complexes[6-9]. So, in this report we aim at testing the effect of hydrothermal synthesis on the formation of the crystal structures of crystalline [Zn(nic)2(H2O)4 ](nic=nicotinic acid).     

Chemical Biology Studies on Molecular Diversity of Annonaceous Acetogenins

Annonaceous acetogenins, isolated from the Annonaceae plants, have been attracting worldwide attention in recent years due to their biological activities, especially as growth inhibitors of certain tumor ceils [ 1 ]. They have been shown to function by blocking complex I in mitochondria [2] as well as ubiquinone-linked NADPH oxidase in the cells of specific tumor cell lines, including some multidrug-resistant ones [3]. These features make these acetogenins excellent leads for the new antitumor agents. In our previous work, the compounds 1a to 1d (Figure 1), which relies on structure simplification while maintaining all essential functionalities of the acetogenins, was in vitro tested against several human solid tumor cell lines and showed interesting cell selectivity [4]. All four analogues show remarkable activity against the HCT-8 and HT-29 cell lines, while compound 1c was found the best [4bi. In order to further investigate the effects of key structural features, a convergent parallel fragments assembly strategy was developed [4e]. In addition, the biological relevancies of typical annonaceous acetogenin mimetics were also studied [4f].     

Synthesis and antitumor activities of novel benzoylphenylurea derivatives.

Seventy novel benzoylphenylurea compounds were synthesized and their antitumor activities were examined in vivo against P388 leukemia. N-(2-Nitrobenzoyl)-N'-[4-(2-pyrimidinyloxy)phenyl]ureas showed the highest antitumor activities when dosed intraperitoneally or orally. Their structure-activity relationships were examined with particular focus on the position and the variety of substituent on each aryl ring.     

Design and Synthesis of Hydrazine and Oxadiazole-containing Derivatives of Sorafenib as Antitumor Agents

A series of hydrazine and oxadiazole analogs of Sorafenib was designed, synthesized and characterized by proton nuclear magnetic resonance(¹H NMR) spectrometry and high resolution mass spectrometry(HRMS). The antiproliferative activities of these compounds against human colorectal carcinoma(HCT-116) and human breast cancer (MDA-MB-231) tumor cell lines were evaluated in vitro by MTT method[MTT=3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide]. The bioassay results suggest that most of the synthesized compounds have antitumor potential to HCT-116 cell line compared with MDA-MB-231 cell line. Compounds 8a,8b,8d, 8e,9f and 9j competitive with Sorafenib demonstrated antiproliferative activities on HCT-116 cell line.     

[1,2,4]三唑并[3,4-b][1,3,4]噻二嗪类衍生物的合成及生物活性研究进展

[1,2,4]三唑并[3,4-b][1,3,4]噻二嗪作为极具前景的活性基团,在抗菌、抗肿瘤等方面具有多种药理活性,在药物和化学领域受到了广泛的关注。本文以含三唑并噻二嗪结构化合物的合成及其在抗肿瘤、抗菌等方面的生物活性为依据,对近几年国内外关于[1,2,4]三唑并[3,4-b][1,3,4]噻二嗪类化合物的研究进行分析总结,以期为后续该类新型抗肿瘤化合物的设计合成提供参考。     

Synthesis,Antitumor Activity and Preliminary Structure-activity Relationship of 2-Aminothiazole Derivatives

In this paper, we described the synthesis of 2-aminothiazole sublibrary containing methyl, bromo, phenyl or butylidene at 4- or/and 5-position of its core. All target compounds were evaluated for their antitumor activities against human lung cancer cell line H1299 and human glioma cell line SHG-44. Among the compounds screened, 4,5,6,7-tetrahydrobenzo[d]thiazole(26b) exhibited the most potent antitumor activities with IC₅₀ values of 4.89 and 4.03 μmol/L against the two tested cell lines, respectively. Preliminary structure-activity relationship(SAR) studies of these compound were subsequently investigated.     

Synthesis and antitumor activities of glucan derivatives

A highly efficient and practical method for the preparation of β-d-Glc-(1→6)-[β-d-Glc-(1→3)]-β-d-Glc-(1→6)-β-d-Glc-(1→6)-[β-d-Glc-(1→3)]-d-Glc-OMe was described. A dendritic nonasaccharide was also synthesized. The antitumor activities of hexasaccharide, the dendrimer, their sulfated derivatives, together with the natural glucan-protein and the corresponding polysaccharide isolated from barmy mycelium of Grifola frondosa, were preliminarily investigated based on Sarcoma-180 studies in mice tests. Our results suggest that the sulfated branching oligosaccharide and natural glycoprotein have better antitumor activities comparing to the parent sugar residue (oligosaccharide or polysaccharide).     

INFLUENCE OF MOLECULAR WEIGHT AND PERIODATE-MODIFICATION OF β-D-GLUCANS FROM PORIA COCOS SCLEROTIUM ON ANTITUMOR ACTIVITIES*

In this work, influence of molecular weight and periodate modification ofβ-D-glucans isolated from Poria cocos sclerotium on the antitumor activities against Sar-coma 180 and Ehrlich ascites carcinoma (EAC) tumor was studied. The results show thattwo glucans PC3 (linear β-(1→3)-D-glucan) and PC4 [β-(1→3)-D-glucan with a fewof branches and glucuronic acid] are devoid of antitumor activity. However, when theglucans were modified by periodate oxidation, borohydride reduction and mild hydrolysisor partially hydrolysis, the derivatives have obvious antitumor activities. The decreasein molecular weight of glucans after periodate modification hardly affects their antitumoractions, but on the other hand, the decrease of molecular weight without periodate modi-fication could lead to an enhancement of the antitumor activities. Moreover, the glucansand these derivatives have much higher enhancement ratios of body weight of mice thanthat of 5-Fluorouracil (5-Fu), suggesting that they are less toxic than 5-Fu.     

Synthesis, chemical characterization and biological screening for cytotoxicity and antitumor activity of organotin (IV) derivatives of 3,4-methylenedioxy 6-nitrophenylpropenoic acid

A series of mono-, di- and triorganotin compounds with general formulae [RSnL(2)Cl], R = Bu (compound 3), [R(2)SnL(2)], where R = Me, Et, Bu, Oct (compounds 1, 2, 4 and 6) and [R(3)SnL], where R = Bu, Cy and Ph (compounds 5, 7 and 8) and where L = 3,4-methylenedioxy-6-nitrophenylpropenoic acid have been prepared and characterized by elemental analysis, multinuclear ((1)H-, (13)C- and (119)Sn-) NMR and mass spectrometry. The ligand and its respective organotin complexes were screened for cytotoxicity using the brine shrimp lethality assay and for antitumor activity using the crown gall tumor inhibition (potato disc) assay. The bioassay results support the conclusion that the biological activities of these synthetic compounds are in the following order: [RSnL(2)Cl] < [R(2)SnL(2)] < [R(3)SnL].     

外式双环[2.2.1]庚烷(庚-5-烯)-2,3-二甲酸酐膦二肽衍生物的合成

选择有机磷基团对斑蝥素的结构骨架进行修饰改造,以外式双环[2.2.1]庚-5-烯-2,3-二甲酸酐为原料,设计合成了一系列斑蝥素类似物。化合物的结构经1HNMR,MS及元素分析确证。     

Synthesis of psymberin analogues: probing a functional correlation with the pederin/mycalamide family of natural products

In this letter we describe an efficient synthesis of "psympederin", a hybrid between the novel antitumor natural product psymberin and the blister beetle toxin pederin. Evaluation of antiproliferative activity reveals that the dihydroisocoumarin fragment is important for psymberin toxicity and the cyclic pederate fragment is important for pederin/mycalamide toxicity. On the basis of preliminary results described herein, we speculate that, despite their structural resemblance, psymberin and pederin/mycalamide induce toxicity through different mechanisms. [reaction: see text].     

Synthesis and antitumor activities of structure-related small molecular compounds of gambogic acid

Through simplifying the complicated skeleton of the natural product gambogic acid, two series derivatives of chromone and xanthone were synthesized and examined for their antitumor activities against several cancer cells in vitro by MTT method. The results showed that appropriate introduction of prenyl group to the small molecular compounds could elevate their antitumor activities. The structure-activities relationship of synthesized compounds certified that the bridgecore in gambogic acid was very important for keeping its antitumor activities.     

Phase Transfer Catalyzed Synthesis of Thiosemicarbazide Derivatives of 2-ethoxybenzoic Acid

A series of 1,4-disubstitued thiosemicarbazides and their related heterocyclic compounds have been found to possess important biological activities[1]. Some thiosemicarbazides have been found to be useful as herbicides, insecticides and plant-growth regulators [1]. In view of these and in continuation of our earlier work on the synthesis and biological activity of thiosemicarbaides derivatives [2], we now report a convenient and efficient method for the preparation of thiosemicarbazides derivatives of 2-ethoxybenzoic acid under the condition of solid-liquid phase transfer catalysis using PEG-400 as the catalyst.     

Halodemetallation of (Z)-1-[2-(Triarylstannyl)vinyl]-cyclooctanol and Correlation of Proton Chemical Shift with Electronegativity

IntroductionOrganotin compounds have attracted attentionas an optimal model for antitumour agents due tothe function of the interesting intramolecularO→Sn coordination[1,2 ] . Our recent concern hasbeen focused on the preparation of ( Z) - 1 - [2 -( triarylstannyl) vinyl]- cyclooctanol[3 ] .In order tofind more appropriate compounds used asanticancer agents and explore the effect of thecoordinate O→ Sn interaction to the antitumoractivity,the new compounds werehalodemetallated and characte…     

Alkylation of nucleic acids by the antitumor agent COMC

[reaction: see text]. Mass spectral data are presented indicating that the antitumor agent 2-crotonyloxymethyl-2-cyclohexenone (COMC) is capable of alkylating oligonucleotides via a mechanism involving an electrophilic exocyclic enone intermediate. Under physiological conditions, the exocyclic enone is likely the glutathionylated 2-exomethylenecyclohexenone. This supports a recent hypothesis that the antitumor activity of COMC arises from alkylation of nucleic acids and/or proteins critical to cell function and not from competitive inhibition of glyoxalase I by an adduct of COMC and glutathione.     

Approach to the synthesis of antitumor quassinoids from labdane diterpenes: an efficient synthesis of a picrasane-related intermediate

[structure: see text]. The tetracyclic ketal 24, a suitable intermediate for the synthesis of antitumor pentacyclic quassinoids, has been efficiently prepared from communic acids (5a-c), via methyl ketone 9. The synthetic sequence from 9 to 24 consists of 15 steps in 12% overall yield.     

柔红霉素和阿霉素自旋标记衍生物的合成与抗肿瘤活性

合成了5个新的柔红霉素及阿霉素的氮氧自由基自旋标记衍生物(5_9),经元素分析,IR,MS和ESR分析确证了其组成和结构,并对它们进行了抑制小鼠白血病P388、小鼠黑色素癌B16、人胃腺癌MGC和人肝癌SMMC7721细胞的体外筛选.初步药理试验表明,化合物5_9对4种瘤株均有一定的抑制活性,其中化合物9的活性与阿霉素相当.     

Synthesis and antitumor activities of water-soluble benzoylphenylureas

Water-soluble benzoylphenylurea derivatives were synthesized as candidate prodrugs and their antitumor activities were examined in vivo against P388 leukemia. Some of the prodrugs were highly soluble in water and showed good antitumor activities against P388 leukemia cells in mice when injected intravenously.     

原子类型电拓扑状态指数预测吲哚喹唑啉衍生物的抗癌性

采用原子类型电拓扑状态指数(ETSIAT)对17个吲哚喹唑啉衍生物的抗癌活性进行定量构效关系(QSAR)的研究. 经逐步回归变量筛选, 得到包含4个ETSIAT变量的最优偏最小二乘模型, 其复决定系数R2、留一法交互验证复决定系数Q2和均方根误差RMSEE分别为0.806、0.736 和0.248. 将样本随机分为训练集和预测集后, 采用相同变量组合对模型进行外部验证, 结果显示模型具有较高的外部预测能力. 模型分析结果显示, 与抗癌活性相关的4个ETSIAT描述子对应结构碎片分别为≥N=, —NH—, =O, >N—. 其中—NH—结构碎片与抗癌活性呈负相关关系, 而≥N=, >N—和=O则与抗癌活性呈正相关关系. 此外, 研究亦显示, 取代基R1上存在强的吸电子基团可显著提高化合物的抗癌活性, 且影响抗癌活性的因素可能还有R2基团的空间位阻效应. 据此设计出4个化合物的预测活性比最高活性样本分别提高7.7%、15.3%、23.1%和130%.