Synthesis and Antiviral Activity of Some 2-Substituted 3-Formyl-and 3-Cyano-5,6-Dichloroindole Nucleosides

A series of dichlorinated indole nucleosides has been synthesized and tested for activity against human cytomegalovirus (HCMV) and herpes simplex virus type-1 (HSV-1) and for cytotoxicity. The isopropylidene-protected analogs of the previously reported 3-formyl-2,5,6-trichloro-1-(β-D-ribofuranosyl)indole (FTCRI) and 3-cyano-2,5,6-trichloro-1-(β-D-ribofuranosyl)indole (CTCRI) were modified by nucleophilic displacement of the 2-chloro substituent using secondary amines. Deprotection of the intermediates provided 2-substituted analogs of FTCRI and CTCRI in good yield. There was a significant difference in reactivity between the isopropylidene-protected and the fully deprotected FTCRI and CTCRI with respect to nucleophilic displacement of the 2-chloro substituent using dialkylamines. This difference in reactivity was not observed with monoalkylamines or with alkoxides, and the corresponding 2-alkylamino- and 2-methoxy substituted analogs were synthesized from FTCRI and CTCRI directly. None of the synthesized analogs demonstrated potent antiviral activity without some corresponding cytotoxicity.     

Synthesis of Novel Difluoro-Cyclopropyl Guanine Nucleosides and Their Phosphonate Analogues as Potent Antiviral Agents

The synthesis of new rigid guanine analogues with anti-HIV-1 and anti-herpes viral activities is described. The phosphonate of difluorocyclopropane nucleoside analogue 26 exhibits in vitro anti-HIV-1 activity similar to that of PMEA in MT-4 cells. Further, analogue 20 shows moderate anti-HCMV activity in MRC cells.     

Synthesis, transport and antiviral activity of Ala-Ser and Val-Ser prodrugs of cidofovir

We report the synthesis and biological evaluation of Ala-(Val-)l-Ser-CO₂R prodrugs of 1, where a dipeptide promoiety is conjugated to the P(OH)₂ group of cidofovir (1) via esterification by the Ser side chain hydroxyl group and an ethyl group (4 and 5) or alone (6 and 7). In a murine model, oral administration of 4 or 5 did not significantly increase total cidofovir species in the plasma compared to 1 or 2, but 7 resulted in a 15-fold increase in a rat model and had an in vitro EC₅₀ value against human cytomegalovirus comparable to 1. Neither 6 nor 7 exhibited toxicity up to 100 μM in KB or HFF cells.     

人巨细胞病毒大外膜磷蛋白pp150羧基末端的高效表达及初步应用

以基因工程抗原取代天然抗原用于人巨细胞病毒（ＨＣＭＶ）感染的诊断,具有广阔的前景。为此,分离ＨＣＭＶ大外膜磷蛋白ｐｐ１５０基因ＯＲＦ３端４３４ｂｐ（编码羧基末端ａａ９４３～ａａ１０４８）的ＤＮＡ片段,导入带有高水平转录启动子Ｐｔｒｃ和六个串联组氨酸的原核表达载体ｐＴｒｃＨｉｓ,在大肠杆菌中得到高效表达,ＳＤＳ ＰＡＧＥ显示一明显的分子量为１５６ｋＤ的融合蛋白条带,ＬＫＢ激光扫描占菌体总蛋白的５１％以上,并且以可溶性形式存在。表达产物经高效特异性纯化后,ＥＬＩＳＡ结果表明其能够与ＨＣＭＶＩｇＭ阳性血清呈特异反应,为建立新一代ＨＣＭＶＩｇＭ检测试剂盒打下了基础。     

Synthesis and Anti-HIV Evaluation of New Acyclic Phosphonate Nucleotide Analogues and Their Bis(SATE) Derivatives

This article describes a very simple route for synthesizing novel lipophilic phosphonate bis(t-bu-SATE) prodrugs of acyclic cyclopentenylated nucleosides such as adenine 17 and cytosine 18. The key intermediate 6 was constructed via a ring-closing metathesis of compound 5, which could be readily prepared from diethylmalonate 4. The chemical stability of the bis(SATE) derivatives was tested at neutral (pH = 7.2) and slightly acid (milli-Q water, pH = 5.5) pH. The synthesized compounds were evaluated as potential antiviral agents against HIV-1 virus.     

Design,Synthesis, and Evaluation of Anti-HBV Activity of Hybrid Molecules of Entecavir and Adefovir: Exomethylene Acycloguanine Nucleosides and Their Monophosphate Derivatives

Exomethylene acycloguanine nucleosides 4, 6 and its monophosphate derivatives 5, 7, and 8 have been synthesized. Mitsunobu-type coupling of 2-N-acetyl-6-O-diphenylcarbamoylguanine (11) with primary alcohols proceeded regioselectively to furnish the desired N⁹-substituted products in moderate yield. Evaluation of 4-8 for anti-HBV activity in HepG2 cells revealed that the phosphonate derivative 8 was found to exhibit moderated activity (EC₅₀ value of 0.29 μM), but cytotoxicity (CC₅₀ value of 39 μM) against the host cells was also observed.     

Synthesis and Antiviral Evaluation of Ribavirin Congeners Containing a Hexitol Moiety

Abstract

Several ribavirin congeners containing a hexitol moiety were prepared via ring opening of two different epoxides with the methylcarboxylate ester of triazole and further elaboration. Unfortunately, none of the newly synthesized compounds displayed appreciable antiviral activity.     

Synthesis,conformational study and antiviral activity of l-like neplanocin derivatives

The l-like enantiomer of 9-(trans-2′, trans-3′-dihydroxycyclopent-4′-enyl)-3-deazaadenine (DHCDA) (1), its 3-deaza-3-bromo derivative (3), and the conformational restricted methanocarba (MC) nucleoside analogues (2 and 4) were synthesized. X-ray crystal structures showed the L isomer MC analogue 4 adopts a similar North-like locked conformation as conventional D-MC nucleosides, while the DHCDA analogue 3 preferred south-like conformer. Compounds 1 and 4 showed potent antiviral activity against norovirus, while compound 2 and 3 were less potent or inactive. The conformational behavior of “sugar” puckering (north/south) and nucleobase orientation (syn /anti) may contribute to the antiviral activity differences. For compound 3, antiviral activity was also found against Ebola virus.     

对HCMV UL54 mRNA 片段特异性切割的M1GS构建

人巨细胞病毒是一种DNA病毒,在人群中一般呈亚临床感染和潜伏感染。为研究病毒基因沉默工具和抗病毒制剂,以人巨细胞病毒UL54基因mRNA序列设计互补的外部引导序列,共价结合到大肠杆菌来源RNaseP催化核心M1RNA上,从而构建成M1GS-T6核酶。通过对DNA聚合酶UL54基因亚克隆片段转录产物体外切割研究,证实该核酶具备对UL54mRNA片段的特异切割能力。     

全球抗病毒药物研发进展与展望

病毒是危害人体健康的主要病原体之一,病毒感染和传播造成的传染性疾病严重威胁人类健康。目前,艾滋病、病毒性肝炎等发病率高、治愈率低的病毒性疾病仍在全球蔓延,流感病毒、冠状病毒等呼吸道病毒不断发生变异,2019年以来,新冠病毒引起的全球疫情对世界各国产生巨大影响,疫情走向还存在很大不确定性,开发安全有效的抗病毒药物成为应对病毒性疾病的重要手段。拟在总结全球抗病毒药物研发整体现状的基础上,分析抗艾滋病病毒、肝炎病毒、新冠病毒等重点领域的新药研发进展,提出抗病毒药物的发展建议,为未来研发更加高效的抗病毒药物提供指引和参考。     

Real-time monitoring of the strand displacement amplification (SDA) of human cytomegalovirus by a new SDA-piezoelectric DNA sensor system

Nucleic acid amplification has long been used in biosensor technologies, such as DNA sensors, DNA chips and microarrays, due to its advantage of high sensitivity in detecting target DNA. However, dynamic monitoring of nucleic acid amplifications with traditional DNA sensors in real-time is difficult since a constant temperature must be maintained during detection. Thus, the piezoelectric sensor, one type of traditional DNA sensor, is not applicable in real-time monitoring PCR due to the dramatic change in temperature that occurs during reaction. In this study, we introduced strand displacement amplification (SDA), an well-developed nucleic acid amplification technique that can work under conditions of constant temperature, into the development of a novel piezoelectric sensor. Using the new SDA-piezoelectric DNA sensor, we designed a stable system for liquid-phase detection, in which the crystal oscillator plate was fixed by an easily adjustable screw-threaded clamping mechanism and successfully applied the new sensor system to real-time SDA monitoring of human cytomegalovirus (HCMV). This new technique overcomes the shortcomings of traditional DNA sensors in real-time monitoring of nucleic acid amplification. The technique has proved to be a markedly simplified procedure with a number of advantages, such as higher sensitivity, better time efficiency, and the ability of dynamic real-time detection.     

Design and Synthesis of Acyclic Nucleoside Analogs with Chlorinated Imidazo[1,2-a]pyridine Bases

Abstract

A series of acyclic C-nucleoside analogs of 2,6-dichloro- and 2,6,7-trichloroimidazo[1,2-a]pyridine were synthesized and tested for antiviral activity. The appropriate hydroxymethyl-substituted heterocycles were treated successively with thionyl chloride, an appropriate nucleophile, then diisopropylethylamine to obtain the desired acyclic nucleoside analogs. These compounds were evaluated for activity against human cytomegalovirus and herpes simplex virus, type 1. Two of the dichloro analogs, but none of the trichloro analogs demonstrated slight antiviral activity (IC₅₀'s = 20–45 µM) at non-cytotoxic concentrations.     

Synthesis and Antiviral Evaluation of Azt Analogues with A Spacer Arm Between Glucidic and Base Moieties. Part II

This article describes the synthesis of a series of AZT analogues bearing an acyclic chain between the sugar and the base moieties is described. These new compounds were readily obtained using microwave irradiation. The compounds were characterized by ¹H NMR and IR spectroscopy. Antiviral (HIV-1) properties of these compounds were examined.     

Synthesis,and in vitro Enzymatic and Antiviral Evaluation of d4T Polyphosphate Derivatives as Chain Terminators

A series of d4T di‐ or triphosphate derivatives have been synthesized and evaluated as effective substrates for HIV‐1 RT, and also tested for their in vitro anti‐HIV activity. The steady‐state kinetic study of compounds 1 – 4 in an enzymatic incorporation assay by HIV‐1 RT follows Michaelis? Menten profile. In addition, compounds 2 – 4 are able to inhibit HIV‐1 replication to the same extent as d4T and d4TMP in MT‐4 cells, as well as in CEM/0 cells and CEM/TK^? cells. The data suggests that these d4T polyphosphate derivatives are hydrolyzed to d4T and rephosphorylated to d4TTP before exerting their antiviral activity.     

Synthesis and Antiviral Evaluation of Novel 2,3-Dihydroxypropyl Nucleosides from 2- and 4-Thiouracils

Regioselective alkylation of 2-thiouracils 1a–c and 4-thiouracils 7a,b with 2,3-O-isopropylidene-2,3-dihydroxypropyl chloride (2) afforded 2-{[(2,2-Dimethyl-1,3-dioxolan-4-yl) methyl]thio}pyrimidin-4(1H)-ones 3a–c and 4-{[(2,2-Dimethyl-1,3-dioxolan-4-yl)methyl]thio} pyrimidin-2(1H)-ones 8a,b, respectively. Further alkylation with 2 and/or 2,3-O-isopropylidine-1-O-(4-toluenesulfonyl)-glycerol (4) gave the acyclo N-nucleosides 5a–c and 9a,b whose deprotection afforded 6a–c and 10a,b. 2-(Methylthio)pyrimidin-4(1H)-ones 11a–c and 4-(methylthio)pyrimidin-2(1H)-ones 14a,b were treated with 2 and/or 4 to give 12a–c and 15a,b which were deprotected to give 13a–c and 16a,b. Pyrimidine-2,4(1H,3H)-dithiones 17a–c were treated with two equivalents of 2 to give 2,4-bis{[(2,2-dimethyl-1,3-dioxolan-4-yl)methyl]thio}pyrimidines 18a–c. Deprotection of compounds 18a–c gave 2,4-bis[(2,3-dihydroxypropyl)thio]pyrimidines 19a-c. The activity of the deprotected nucleosides against Hepatitis B virus was evaluated and showed moderate inhibition activity against HBV with mild cytotoxicity.     

Design and Synthesis of Indole and Tetrahydroisoquinoline Hydantoin Derivatives as Human Chymase Inhibitors

The synthesis of new potential inhibitors of human chymase is described. Treatment of dihydroimidazo[1,5-a]indole and [1,5-b]isoquinoline-dione with thioaryl followed by oxidation gave the N-arylsulfonylmethyl of polycyclic hydantoin derivatives 3, 5 and 6.     

Histone Deacetylase Inhibitor SAHA Induces Expression of Fatty Acid-Binding Protein 4 and Inhibits Replication of Human Cytomegalovirus

Virologica Sinica - Suberoylanilide hydroxamic acid (SAHA) is a histone deacetylase inhibitor that shows marked efficacy against many types of cancers and is approved to treat severe metastatic...     

人巨细胞病毒磷蛋白65及糖蛋白B在大肠杆菌中的高效表达、免疫原性研究及初步应用

实验成功的构建了含有pp65与gB主要抗原决定簇基因的表达质粒pET-pp65、pET-gB;表达产物通过SDS-聚丙烯酰胺凝胶电泳、免疫印迹、间接酶联免疫等一系列鉴定试验进行了分析。表达蛋白经初步纯化后免疫BALB/c小鼠,经0、2、4周免疫三次,免疫后2、4、6周眼眶采血收集抗血清,进行中和试验和ELISA检测。动物试验表明两种表达蛋白具有免疫原性,并可在小鼠体内诱导产生特异性抗体,其中用重组gB蛋白免疫小鼠后得到的抗血清在体外试验中能抑制天然病毒感染细胞。同时将这两种表达蛋白作为诊断用抗原,对临床94份血清进行检测,证实pp65具有较好的特异性,为今后研制HCMV诊断试剂提供了科学依据。