2'''',3''''-双脱氢-2'''',3''''双脱氧胸苷5''''-亚磷酸苄酯的ESI-MS~n中的一种新颖的重排反应

爱滋病(AIDS)是一种严重威胁人类健康的传染性疾病。研究和开发新的、高疗效的抗AIDS的药物已成了生物学家、化学家和药物学家的主要的研究方向之一。2',3'-双脱氢.2',3'-双脱氧胸苷(d4T)是HIV逆转录酶抑制剂,它们是美国FDA通过的可用于治疗AIDS的一类药物。由于d4T等本身对HIV无活性,只有经细胞代谢成5'-磷酸化产物后才对HIV产生抑制作用,因此很有必要对d4T进行结构改造,而对上述药物的结构进行改造是研制新的抗AIDS的化学药物最简捷的途径。因此,我们合成了一系列的d41、5'-亚磷酸酯的衍生物,并对它们的电喷雾质谱进行了详细的研究。研究发现了2',3'-双脱氢,2',3'双脱氧胸苷(d4T)-5'-氢亚磷酸苄酯的一种新颖的重排反应,并对其机理进行了进一步的研究。有关结果不仅有助于对这类化合物的结构分析,而且对它们的合成、药物性质以及药物代谢等方面的研究都具有重要意义。     

核苷5'-硫代磷酰氨基酸酯电喷雾质谱研究

核苷磷酰氨基酸酯化合物是1类倍受重视的药物,特别是它可作为寡聚核苷酸的类似物用于反义药物[1].核苷逆转录酶抑制剂被批准用于治疗爱滋病(AIDS),目前普遍使用的抗HIV核苷类似物中,2',3'-双脱氧核苷(ddNs)具有良好的疗效[2],它的抗病毒的可能机理是在细胞激酶的作用下,5'-羟基发生相继的磷酸化生成三磷酸核苷,然后通过HIV-逆转录酶进入病毒DNA的合成,由于ddNs 3'-位没有相应的羟基存在,使得病毒DNA的合成得以终止.     

2′,3′-乙氧甲撑基腺苷5′-硫代磷酰氨基酸酯的合成和谱学分析

核苷磷酰氨基酸酯化合物是一类倍受重视的药物 ,特别是它可作为寡聚核苷酸的类似物用于反义药物 [1] .HIV逆转录酶是治疗艾滋病的有效靶点 ,目前普遍使用的抗 HIV核苷类似物中 ,2′,3′-双脱氧核苷 (dd Ns)具有良好的疗效 [2 ] .苯氧基取代的核苷 -磷酰氨基酸酯是 HIV逆转录酶的有效抑制剂[3 ] ,其药物毒性比 dd Ns低 ,但容易在体内被核酸酶水解 .由于硫代磷酸对核酸酶具有抵抗性 ,它可以抑制核酸酶对它的水解 [4 ] ,因此我们设计合成了核苷 5′-硫代磷酰氨基酸酯化合物 ,希望开发出一种全新的 HIV逆转录酶抑制剂 .由于分子中引入氨基…     

含长碳烷基核苷氢亚磷酸酯衍生物的合成与表征

通过将抗病毒药物核苷(3'-叠氮-2',3'-二脱氧胸苷AZT或2',3'-二脱氢-2',3'-二脱氧胸苷d4T)与三氯化磷反应, 然后在不同的醇解试剂作用下, 一锅法合成得到6个含长链烷基的核苷氢亚磷酸二酯衍生物, 并采用³¹P NMR, ¹H NMR, ¹³C NMR和ESI-MS对其结构进行了表征.     

1'-C-氰基-2',3',5'-三-O-苯甲酰基-β-D-呋喃胸苷的声化学合成

本文首次应用超声波技术合成了1'-C-氰基-2',3',5'-三-O-苯甲酰基-β-D-呋喃胸苷, 反应时间1h, 产率96-100%, 与通常的化学合成方法相比, 反应速度及产率大辐度提高。     

2-芳胺基-5-[5'-氨基-1'-(4"-氯苯基)-1',2',3'-三唑-4'-基]-1,3,4-噻二唑的合成

1-[5'-氨基-1'-(4"-氯苯基)-1,2,3-三唑-4'-甲酰基]-4-芳基-3-氨基硫脲在浓硫酸催化下环化得到2-芳胺基-5-[5'-氨基-1'-(4"-氯苯基)-1',2',3',-三唑-4'-基]-1,3,4-噻二唑2a-i, 依此法合成了九个标题化合物, 收率为30-74%。化合物2i的结构用X-光衍射单晶分析确证。     

酶促合成2'',3''-双脱氧双脱氢-5-氟胞嘧啶核苷的研究

从瑞士乳酸杆菌Lactobacillus helveticus(ATCC8018)中提取了N-脱氧核苷转移酶进行催化合成抗病毒药物2',3'-双脱氧双脱氢-5-氟胞嘧啶核苷(D-D4F℃)的反应.考察了反应时间、反应液的pH值、缓冲液以及反应底物浓度对反应产率的影响.     

1-(2'-苯基-1', 2', 3'-三唑-4'-甲酰基)-4-芳基氨基硫脲及其 环化产物的合 成

以2-苯基-1,2,3-三唑-4-甲酰肼为原料合成了几种新的1-(2'-苯基-1',2',3'-三唑-4'-甲酰基)-4-芳基氨基硫脲,在不同条件下环化,制得一系列新的1,3,4-噻二唑、1,3,4-恶二唑和1,2,4-均三唑衍生物。化合物的结构经元素分析、IR、^1HNMR和MS确证,并对其波谱性质进行了讨论。     

由2',4'-二氢-6'-甲氧基-3',5'-二甲基查耳酮合成新黄酮

在DMSO/ I2的氧化作用下,由2',4'-二氢-6'-甲氧基-3',5'-二甲基查耳酮可合成一种全新结构的黄酮:7-羟基-5-甲氧基-6,8-二甲基黄酮(产率91%),而在HCl/MeOH作用下则得到了两种黄烷酮:7-羟基-5-甲氧基-6,8-二甲基黄烷酮 (产率70%) 和 5,7-二羟基-6,8-二甲基黄烷酮 (产率20%).     

酰氨基硫脲及相关杂环衍生物的研究XXIX: 2-(3'-溴苯胺基)-5-[5'-氨基-1'-(4"-氯苯基)-1',2',3'-三唑-4'-基]-1,3,4-噻二唑的晶体结构

经1-[5'-氨基-1'-(4"-氯苯基)-1',2',3'-三唑-4'-甲酰基]-4-(3'-溴苯基)-3-氨基硫脲在浓硫酸作用下制得2-(3'-溴苯胺基)-5-[5'-氨基-1'-(4"-氯苯基)-1',2',3'-三唑-4'-基]-1,3,4-噻二唑化合物。该化合物的晶体结构经X射线衍射分析确定, 化合物属三斜晶系, P1空间群, a=1.1784(2), b=1.4455(2),c=1.1353(1)nm; α=100.68(1), β=109.50(1), γ=79.89(1)°; V=1.7779nm^3; 分子式C~1~6H~1~1BrClN~7S, Mr=448.75; Dc=1.673g/cm^3, Z=4,μ=58.16cm^-^1, 最终偏离因子R=0.084, Rw=0.086。分析化合物的键长, 键角数据表明, 该分子具有离域π键结构。     

2-芳胺基-5-[5'-氨基-1'-(4''-氯苯基)-1', 2', 3'-三唑-4'-基]——-1, 3, 4-恶二唑的合成

利用1-[5'-氨基-1'-(4'-氯苯基)-1', 2', 3'-三唑-4'-甲酰基]-4-芳基氨基硫脲在汞盐Hg(OAc)2-HOAc中加热缩合, 制得11种新的2-芳胺基-5-[5'-氨基-1'-(4'-氯苯基)-1', 2', 3'-三唑-4'-基]---1, 3, 4-恶二唑。所有化合物的结构经元素分析, IR、MS以及1H NMR确认。选择代表物作生测试验, 结果表明, 2b, 2k中MIC3.1mg/L时, 对大肠杆菌及金黄色葡萄球菌繁殖有明显抑制。     

四氢苯并[4',5']噻吩并[3',2':5,6]吡啶并[4,3-d]嘧啶-4(3H)-酮的合成、晶体结构及杀菌活性

通过氮杂Wittig反应合成了一系列结构新颖的未见文献报道的取代四氢苯并[4',5']噻吩并[3',2':5,6]吡啶并[4,3-d]嘧啶-4(3H)-酮化合物6, 产物的结构通过核磁共振氢谱、质谱、红外光谱、元素分析的确证. 为进一步了解此类化合物的结构, 对化合物6c进行了X射线单晶衍射. 初步杀菌活性测定结果表明, 该类化合物具有较好的杀菌活性和选择性. 如6f在50 mg/L浓度时, 对黄瓜灰霉菌的抑制率为98%.     

Total synthesis of 2',3',4',5',5' '-(2)h(5)-ribonucleosides: the key building blocks for NMR structure elucidation of large RNA

The diastereospecific chemical syntheses of uridine-2',3',4',5',5' '-(2)H(5) (21a), adenosine-2',3',4',5',5' '-(2)H(5) (21b), cytidine-2',3',4',5',5' '-(2)H(5)(2)H(5) (21c), and guanosine-2',3',4',5',5' '-(2)H(5) (21d) (>97 atom % (2)H at C2', C3', C4', and C5'/C5' ') have been achieved for their use in the solution NMR structure determination of oligo-RNA by the Uppsala "NMR-window" concept (refs 4a-c, 5a, 6), in which a small (1)H segment is NMR-visible, while the rest is made NMR-invisible by incorporation of the deuterated blocks 21a-d. The deuterated ribonucleosides 21a-d have been prepared by the condensation of appropriately protected aglycone with 1-O-acetyl-2,3,5-tri-O-(4-toluoyl)-alpha/beta-D-ribofuranose-2,3,4,5,5'-(2)H(5) (19), which has been obtained via diastereospecific deuterium incorporation at the C2 center of appropriate D-ribose-(2)H(4) derivatives either through an oxidation-reduction-inversion sequence or a one-step deuterium-proton exchange in high overall yield (44% and 24%, respectively).     

Synthesis and Biological Activity of Novel 2,3-Dihydro-2-phenylsulfonylhydrazono-3-(2'',3'',4'',6''-tetra-O-acetyl-β-D-glucopyranosyl)thiazoles

A series of novel 2,3-dihydro-2-phenylsulfonylhydrazono-3-(2',3',4',6'-tetra-O-acetyl-β-D-glucopyranosyl)thiazoles were designed and synthesized via the reaction of thiosemicarbazide with chloroaldehyde. Their chemical structures were characterized by 1H and 13C NMR spectroscopy and elemental analysis. The bioassay results indicate that some of these compounds exhibit moderate fungicidal and herbicidal activities.     

Synthesis and antibacterial activity of brominated 2''(4'')-nitro-3-hydroxy diphenyl ethers

Eight new brominated 2'(4')-nitro-3-hydroxy diphenyl ethers have been designed and synthesized.The structures of new compounds were confirmed by 1H NMR.IR and HRMS.The bioactivity tests showed that these compounds possessed antibacterial activities against the tested bacteria.These new compounds cannot be transformed into dioxins when they were manufactured and used.     

Synthesis and mesomorphic properties of 4-methoxyphenyl 4'- n -alkoxy-2',3',5',6'-tetrafluorobiphenyl-1-carboxylates

A novel type of 4-methoxyphenyl 4'- n -alkoxy-2',3',5',6'-tetrafluorobiphenyl-1-carboxylates have been synthesized. Textural observations by polarizing microscopy and DSC measurements of the phase transitions show that all of these compounds are thermotropic liquid crystals with only a nematic mesophase. The relationship between the properties and chemical structures of these compounds is discussed.     

Synthesis of N-Aryl-2- (1'' , 6'' -dihydro-6'' -pyridazinone-3''-carbonyl) Thiosemicarbazides and Their Related Heterocyclic Compounds

1,6-Dihydro-3-hydrozinocarbonyl-6-pyridazinone(compound 2) were prepared from α-ketoglutaric acid and hydrazine hydrate. A series of N-aryl-2-(1' ,6'-dihydro-6'-pyridazinone-3'-earbonyl) thiosemicarbazides 3a-3f were synthesized from the reaction of aryl isothiocyanates with compound 2. The terminal compounds 1,3, 4-thiadiazole, 1,3,4-oxadiazole and 1,2, 4-triazol-5-thione derivatives were cyclized from compounds 3a-3f. Their structures were confirmed by IR, 1H NMR, MS and elemental analyses.     

Synthesis of (2S,3R)-[3',3',3'-2H3]-valine and (2S,3S)-4-fluorovaline

A new synthesis of (2S,3R)-[3',3',3'-2H3]-valine has been completed and (2S,3S)-4-fluorovaline has been synthesised for the first time. Both compounds have been prepared by routes involving stereoselective addition to the (S)-pyroglutamate derivative and are available for studies in several areas of bio-organic chemistry.     

3',5'/2',5'-连结的二和三腺苷酸甲基膦酸酯的合成及用^1H,^31PNMR研究P的构型

本文报导了3',5'/2',5'-连结的二和三腺苷酸甲基膦酸酯的合成,分离了它们的非对映立体异构体.用紫外,核硝氢谱和磷谱证实了它们的结构,用NOE研究了每个立体异构体中磷的构型,并讨论了合成中立体专一性的机理.