Synthesis of New Fluorinated Podophyllotoxin Derivatives

Five fluorinated podophyUotoxin derivatives were synthesized using dimethylamino-sulfurtrifluoride (DAST).     

Synthesis and Anticancer Activity of Podophyllotoxin Derivatives

Chemistry of Natural Compounds - Two series of podophyllotoxin derivatives were synthesized by addition of a 4β-sulfanilamide to or substitution of a 4β-amide into podophyllotoxin. Their...     

Design,Synthesis and Antitubulin Activity of Novel Podophyllotoxin Derivatives as Potent Anticancer Agent

Twenty novel podophyllotoxin derivatives(1―20) were designed and synthesized. The anti-proliferation activities of these compounds were evaluated against three human cancer cell lines(HepG2, Calu-1 and MCF-7) using podophyllotoxin and Combretastatin A4(CA-4) as positive controls. Among all the compounds, compound 2 displayed more significant anti-proliferation activities against MCF-7 and Calu-1 cell lines and showed lower toxicity towards non-cancer cells. Furthermore, the cell cycle and apoptosis analysis results revealed that compound 2 can cause cell arrest at G2/M phase, leading to cancer cell apoptosis. Meanwhile, it can also reduce the adhesive ability of Calu-1 cells to fibronectin and laminin. The docking simulation results demonstrated that compound 10 can nicely bind to the colchicine site of tubulin. The podophyllotoxin derivatives are worthy to be further investigated to obtain more potent anti-cancer drugs.     

Synthesis of New Spin Labeled Derivatives of Podophyllotoxin as Potential Anticancer Agents

AsaresultOfthedevlOPmentOfetOPOSide(VPl6)andteaiPOSide(VM-26)asanticancertw,thesendSynheticanalOgUsOfthenaturailyoccuning~OtOkin(l)havebomuchrenewedinterestinrecentyears.Inourprevioushees",wefOundthatanumterOfhitroXy1opnltheledderivativesOf~yllOtoxinhadsignfficantanticancerAnvitywithInareddecreaseintoxidtycomParedwiththeParentcompoundlandVPl6.AseriesofSPinldeledderibovesOfthio-TEPA,'`,nitrosourea',andruboInyin8werealsoreportedtohavSUPeriorpharmaCOledtalpmprtiestotheirparentco…     

Novel Access to Furan-3-thiols and Derivatives,Impact Meat-Flavor Compounds

A versatile process for the preparation of a number of 3-thio-substituted furans 1–4 is described. These products have very low odor thresholds and are thus potent flavor compounds. Fur-3-yl thiocyanates 10a , b as well as other S-containing analogues ( 2b , 7a , b , and 8 ) were prepared by a Michael-type addition of thiocyanic acid, thioacetic acid, alakanethiols, and sodium thiosulfate to alkynones 6 or 15 , followed by cyclization (Schemes 3 and 4). The thiocyanates 10a, b were converted to mixed disulfides 3 , symmetric disulfides 4 , thioethers 2 , and thiols 1 , using ‘hard’ or ‘soft’ nucleophiles or reducing agents, respectively (Scheme 6).     

鬼臼毒素衍生物的EIMS谱分析研究

鬼臼毒素及其衍生物由于具有抗肿瘤活性而引起人们对其结构、性能及合成产生的极大兴趣[1],它们的质谱研究也曾有报道[2,3].本文报道4种衍生物的EIMS谱的分析结果,它们的结构如下:     

A Rapid Access to Novel and Known Benzimidazole Derivatives Using Silica Chloride as a Reusable Catalyst

A new application of silica chloride as an easily available and reusable solid acid catalyst for the synthesis of benzimidazole and its derivatives through the condensation of o‐phenylenediamines and orthoesters under thermal and solvent‐free conditions is described. This novel and eco‐friendly method is very cheap and has many advantages including excellent yields, short reaction time, and simple work‐up procedure.     

A New Route to Some Novel Phosphole Derivatives

Abstract

Previous work has shown that the unstable five co-ordinate phospholes (1; R=alkoxy, R′=alkyl) produced in the reaction of trialkyl phosphites with a two molar equivalent of dimethyl acetylenedicarboxylate can be converted into the novel phospholes (2; R=alkoxy) by treatment with hydrogen bromide at low temperature. We have now shown that a similar approach can be used to generate the phospholes (2; R=alkyl, aryl) by using dialkyl alkylphosphonites or dialkyl arylphosphonites rather than trialkyl phosphites. However, the reduced stability of the phosphorane intermediates (1; R=alkyl, aryl, R′=alkyl) relative to those produced in the trialkyl phosphite reactions means that these trapping reactions are difficult to carry out successfully.     

The Synthesis of Podophyllotoxin Derivatives with Macrocyclic Dilactone

Podophyllotoxin1andmanyofitsderivatives,includingC-2epimer,picropodophyllin2.areantimitoticagents'.Thesemi'syntheticderivativesofIetoposide(VP-16-213)andteniposide(VM-26)areinclinicaluseasanti-canceragents'.SomeanaloguesofIwithamodifiedlactoneringhavebeensynthesizedandfoundtobestillantimitotic'.therebyindicatingthatthelactoneringisnotrequiredforantimitoticactivityin1.Anjanamurthyetap.ha.esynthesizedaderivativebyenlargingthefive-memberedlactoneringinItoasix-memberedone.Sincethen.however.nos…     

Synthesis and Characterization of a Novel Podophyllotoxin Derivative Containing a Cyclohexadienone Group

4β-Azido-4-demethyl-4'-O-demethyl-epipodophyllotoxin reacted with phenyliodonium diacetate in MeOH at room temperature to synthesize a novel podophyllotoxin derivative containing a cyclohexadienone group with the original configurations of C2 and C4,which are required for the antitumor activities.The component and structure of the pro-duct were confirmed using elemental analysis,high-resolution mass spectrum,1H and 13C NMR spectra,and infrared spectrum.Furthermore,the fragmentation routes of the product were fully assigned with electron-impact time-of-flight mass spectrometry(EI-TOF MS),which can also be used for the structural elucidation based on the molecular ion at m/z 455(16%)and three novel characteristic fragment ions at m/z 183(37%),425(7%),and 199(5%).The cyclohexadienone product is sensitive to acidic media.When it is treated with a trace of acid,another novel derivative containing an orthoquinone moiety is formed,which links with the metabolism of the cancer inhibitors.     

鬼臼毒素及其衍生物的瞬态粒子分析

分析了鬼臼毒素及其衍生物与还原性自由基(氢自由基、水合电子)作用、氧化性自由基羟基自由基和激光等作用后产生的各种瞬态粒子，对各粒子的生成和衰减过程进行跟踪，获得了各瞬态粒子的生成和衰减速率常数，进一步探讨了鬼臼毒素治疗肿瘤的构效关系。     

New Access to Pseudo-ionones andPseudo- iso -methyl Ionones from Geranyl Derivatives

Abstract

Pseudo-ionones and pseudo-iso-methyl ionones, precursors of fragrant derivatives were obtained from geranyl chloride, an industrially available starting material.     

Synthetic Access to New Carbamate and Thiocarbamate Derivatives from Pyridinecarbaldehyde Oximes and Hydroxypyridines

The synthesis of pyridine carbamate and thiocarbamate derivates is described. A series of oxime carbamate and thiocarbamate derivatives were synthesized by the addition of 2-, 3-, and 4-pyridinecarbaldehyde oximes to isocyanates and isothiocyanates. Furthermore, carbamate and thiocarbamate derivatives of pyridine were synthesized by the addition of 2-, 3-, and 4-hydroxy pyridine to isocyanates and isothiocyanates. Their structures were confirmed by both analytical and spectral data.

鬼臼毒素及其衍生物热分解反应的动力学研究

The thermal behavior and thermal decomposition kinetic parameters of podophyllotoxin （1） and 4 derivatives, picropodophyllin （2）, deoxypodophyllotoxin （3）, fl-apopicropodophyllin （4）, podophyllotoxone （5） in a temperature-programmed mode have been investigated by means of DSC and TG-DTG. The kinetic model functions in differential and integral forms of the thermal decomposition reactions mentioned above for first stage were established. The kinetic parameters of the apparent activation energy Ea and per-exponential factor A were obtained from analy- sis of the TG-DTG curves by integral and differential methods. The most probable kinetic model function of the decomposition reaction in differential form was （1- a）^2 for compounds 1-3,2/3·a^-1/2 for compound 4 and 1/2（1-a）·[-In（1-a）]^-1 for compound 5. The values of Ea indicated that the reactivity of compounds 1-5was increased in the order： 5〈4〈2〈1〈3. The values of the entropy of activation △S^≠, enthalpy of activation △H^≠ and free energy of activation △G^≠ of the reactions were estimated. The values of △G^≠ indicated that the thermal stability of compounds 1-3 with the samef（a） was increased in the order： 2〈3〈1.     

自旋标记鬼桕类化合物圆二色谱的研究

给已知抗癌药物分子中引入稳定氮氧自由基,合成较母体药物高效低毒的抗癌药物已引起国内外学者的重视.我们在具有抗癌活性的鬼桕毒分子中引入稳定氮氧自由基,药理试验表明其活性保持或增加,而毒性却显著地降低.     

抗癌活性鬼臼毒素衍生物的合成与构效关系研究

合成了１３个新的鬼臼毒素衍生物５－１７，经元素分析ＩＲ，ＭＳ，ＥＳＲ和＾１ＨＮＭＲ分析确证了其组成和结构，并对它们进行了抑制小鼠淋巴白血病Ｐ３８８和人胃腺癌ＳＧＣ－７９０１细胞体外筛选，发现新化合物５，７－１０对两种瘤株均有显著抑制活性，４′－Ｏ－去甲基鬼臼毒素５，１０－１３的抗癌活性大于相应的４′－甲氧基类似物６，１４－１７，用“－Ｏ－”桥取代Ｃ－４位的“－ＮＨ－”桥可导致抗癌活性降低。     

Synthetic Access to New Pyridone Derivatives through the Alkylation Reactions of Hydroxypyridines with Epoxides

General methods for the preparation of a variety of pyridone and oxypyridine derivatives are described. 2‐,3‐,4‐Hydroxy pyridine and 2‐pyridinemethanol were alkylated with ethylene‐, propylene‐, and stryrene‐oxide and epichlorohydrin in the presence of different Lewis acids as a catalyst. The best yield of 3a was achieved in the presence of CdI₂/BF₃ · OEt₂. The corresponding pyridone derivatives (3a–d, 7a–d) were obtained from the reaction of 2‐and 4‐hydroxypyridine with oxiranes in good yields, whereas oxypyridine derivatives (5a–d, 9a,b) were obtained from reactions of 3‐hydroxypyridine and 2‐pyridinemethanol with oxiranes. Chlorohydrines (3d, 5d, 7d) were easily converted to corresponding epoxy derivatives (10, 11, 12) in basic medium; then amino alcohols (13–17) were obtained from the reaction of these epoxy derivatives with amines.