葡萄糖-β-(1→4)-半乳糖二糖片段的合成

目的 利用化学方法高效合成葡萄糖-β-(1→4)-半乳糖二糖片段。方法 以4,6位苄叉保护的葡萄糖硫苷11为原料通过4步反应以39%的产率合成了硫苷供体15 ,再以TMSOTf与NIS作为促进剂,硫苷供体15与低活性的半乳糖受体18进行糖苷化反应合成葡萄糖-β-(1→4)-半乳糖二糖2。 结果 糖苷化反应以81%的产率得到葡萄糖-β-(1→4)-半乳糖二糖2, 为新型海洋天然产物Ancorinoside A的合成提供物质基础和技术保障。     

抗高血压药物阿利克仑的合成研究

目的 研究抗高血压药阿利克仑的化学合成方法。方法 以光学纯中间体(3S,5S,1′S,3′S)-5-(1′-叠氮基-3′-羟甲基-4′-甲基戊基)-3-异丙基二氢呋喃-2-酮为起始原料,经氧化、亲核加成、氢化、Boc 保护、氨解、脱保护等反应得到阿利克仑游离碱。结果与结论 以总收率 35.7 % 合成阿利克仑。该合成路线反应步骤简短,操作简便,收率高,反应条件温和,适合工业化生产。     

10-去乙酰基-7-表紫杉醇转化为紫杉醇的研究

目的将天然紫杉烷类物质10-去乙酰基-7-表紫杉醇高效地转化为抗癌药物紫杉醇.方法首先将10-去乙酰基-7-表紫杉醇中的2'-OH选择性保护、7-OH乙酰化、去保护3步一锅反应获得7-表紫杉醇,再在DBU的催化下差向异构化为紫杉醇.结果本方法以10-去乙酰基-7-表紫杉醇为起始原料,以40%的总收率制备得到紫杉醇.结论建立了一条将天然紫杉烷类物质以较高的化学选择性以及良好的收率转化为紫杉醇的途径.     

血吸虫病化学治疗的研究 Ⅱ.α-取代-β-(5-硝基-2-呋喃)丙烯酰胺及酯类衍生物的合成

本文报导α-取代-β-(5-硝基-2-呋喃)丙烯酰胺及酯类衍生物85个的合成。这类化合物系分别以糠醛或硝基糠醛与相应的羧酸钾盐经Perkin反应缩合后,按一般方法制成酰胺及酯;或以相应的硝基呋喃丙烯酰胺经溴化;或通过氮内酯中间体经水解、醇解和氨解而制备。经动物篩选后发现有13个化合物对感染日本血吸虫小白鼠有作用,其中α—甲基—β-(5-硝基-2-呋喃)丙烯酰正丁胺(I_6,F-30058),α-甲基-β-(5-硝基-2-呋喃)丙烯酰乙醇胺(I_(10),F-30141)及α-甲基-β-(5-硝基-2-呋喃)丙烯酰-2′-羟基丙胺(I_(11),F-30111)三个具有较好抑制作用。     

3-甲基-5-硝基呋喃衍生物的合成

本文报道在硝基呋喃类药物的呋喃环3位上进行结构修饰。根据3位甲基有利于硝基与酶活性部位的巯基进行亲核取代,有可能提高其抗菌杀虫活性的设想,合成了3-甲基呋喃嘧酮和3-甲基呋喃丙胺等新化合物19个。与母体化合物进行抗菌杀虫活性的比较,以探索环上甲基所起的作用。这类化合物的合成是以丙酮为原料,经Claisen缩合、Darzen反应、McFadyen反应成为3-甲基呋喃甲醛,再经Knoevenagel反应、硝化、缩合成为化合物Ⅰ。3-甲基呋喃醛经肟化、硝化、缩合成为化合物Ⅱ。有关生物活性比较和理论探讨将另文发表。     

(6R,7R)-7-[2-呋喃基(甲氧亚氨基)乙酰氨基]-3-羟甲基-8-氧代-5-硫杂-1-氮杂二环[420]辛-2-烯-2-甲酸的合成研究

目的　制备(6R,7R) - 7-[2 -呋喃基(甲氧亚氨基)乙酰氨基] - 3-羟甲基- 8-氧代- 5 -硫杂- 1-氮杂二环[4 2 0]辛- 2 -烯- 2 -甲酸。方法　通过7-氨基头孢烷酸的水解,生成去乙酰基7-氨基头孢烷酸,再与2 - (2 -呋喃基)- 2 -甲氧亚胺基乙酸氯反应进行7位氨基的酰化制备上述医药中间体。结果及结论　适宜的反应条件为:7-氨基头孢烷酸在- 2 5℃水解,与2 - (2 -呋喃基) - 2 -甲氧亚胺基乙酰氯在- 10℃反应,二者的摩尔比为1 0∶1. 15,收率可达80 %。     

抗肿瘤药物2′-脱氧-5-氟尿苷合成研究

目的:合成抗肿瘤药物2′-脱氧-5-氟尿苷。方法:以5-氟尿嘧啶核苷为原料,经丙酰溴酰化溴代得2′-溴代-3,′5′-O-二丙酰基-5-氟尿嘧啶核苷,然后氢化得产物2′-脱氧-3,′5′-O-二丙酰基-5-氟尿嘧啶核苷,最后经皂化合成2′-脱氧-5-氟尿苷。结果:以5-氟尿嘧啶核苷为起始原料经3步反应合成了2′-脱氧-5-氟尿苷。结论:本合成方法工艺简便,原料易得,条件温和,总收率为72.0%,适于工业制备。     

N6-苯甲酰基-2'-叔丁基二甲基硅氧基腺苷-3'-H-膦酸的合成工艺研究

目的 研究N~6-苯甲酰基-2′-叔丁基二甲基硅氧基腺苷-3′-H-膦酸的合成工艺。方法 以腺苷为起始原料,先对腺苷的嘌呤氨基进行苯甲酰基保护,再分别向腺苷的5′位和2′位引入二甲氧基三苯甲基(DMT)和叔丁基二甲基硅基(TBDMS)保护基,制备得到关键中间体N~6-苯甲酰基-5′-二甲氧基三苯甲氧基-2′-叔丁基二甲基硅氧基腺苷(3)。中间体3与磷试剂2-氯-4H-1,3,2-苯并二氧磷杂环己烷-4-酮反应引入膦酸基团,最后使用二氯乙酸脱除DMT保护基得到目标产物。结果 经过5步反应得到了目标化合物N~6-苯甲酰基-2′-叔丁基二甲基硅氧基腺苷-3′-H-膦酸,并利用~1H-NMR、~(31)P-NMR、质谱等方法确证了其结构。本合成工艺的总收率为35.7%,目标化合物的质量分数为98.5%。结论 该合成工艺与原有方法相比步骤短,操作简单,具有良好的应用前景。     

3-脱克拉定糖-3-酮基-6-O-甲基-10,11-脱氢-12-O-咪唑酰基-2′-苯甲酰基红霉素A的合成

目的合成制备泰利霉素的关键中间体。方法以3-脱克拉定糖-3-酮基-6-O-甲基-2′-苯甲酰基红霉素A为起始原料,经过甲磺酯化、碱消除、咪唑酰基化三步成功地合成关键中间体3-脱克拉定糖-3-酮基-6-O-甲基-10,11-脱氢-12-O-咪酰基-2′-苯甲酰基红霉素A,并进行了工艺改进。结果与结论新的合成工艺与未改进时相比,总收率提高10%,为科研和工业化生产奠定基础。     

N4-烷基-5-甲基-2′-脱氧胞苷的合成

3′,5′-O-二苯甲酰胸苷在三氯氧磷存在的条件下与1,2,4-三唑缩合可得到1-(3′,5′-O-二苯甲酰-β-D-呋喃核糖)- 4-(1,2,4-三唑-1-基)-5-甲基-嘧啶-2-(1H)-酮,再用不同的胺取代核苷C4上的三唑基团可制备一系列全新的N4-烷基取代的5-甲基胞苷.方法简便 ,收率高.     

Systematic synthesis and biological evaluation of alpha- and beta-D-xylofuranosyl nucleosides of the five naturally occurring bases in nucleic acids and related analogues

The alpha- and beta-D-xylofuranosyl analogues of the naturally occurring nucleosides, as well as other D-xylofuranosyl derivatives, have been the subject of a systematic synthesis and examination of their biological, i.e. antiviral antimetabolic, and cytostatic properties. The beta anomers were prepared by glycosylation of purine and pyrimidine aglycons with peracylated 1-O-acetyl-alpha-D-xylofuranoses, followed by removal of the blocking groups. The alpha anomers were obtained by a multistep synthesis with use of 2-amino- or 2-mercapto-alpha-D-xylofuran[1',2':4,5]-2-oxazoline as starting material. The xylofuranosyl nucleosides were tested for their activity against a variety of RNA and DNA viruses and for inhibition of cell growth and macromolecule synthesis. Three compounds, 9-(beta-D-xylofuranosyl)adenine, 9-(beta-D-xylofuranosyl)guanine, and 1-(beta-D-xylofuranosyl)cytosine, showed marked biological activity.     

Spinoside,new coumaroyl flavone glycoside from<Emphasis Type="Italic">Amaranthus spinosus</Emphasis>

Spinoside, new coumaroyl flavone glycoside was isolated from the n-butanol fraction of the mathanolic extract of the whole plant of Amaranthus spinosus and assigned the structure 7-p-coumaroyl apigenin 4-O-beta-D-glucopyranoside (1) on the basis of spectroscopic techniques including 1D and 2D NMR spectroscopy. In addition alpha- xylofuranosyl uracil (2), beta-D-ribofuranosyl adenine (3) and beta-sitosterol glucoside (4) have also been isolated for the first time from this species.     

Antimicrobial activity of new synthesized [(oxadiazolyl)methyl]phenytoin derivatives

A number of substituted phenytoin derivatives in addition to their sugar hydrazones were newly synthesized. Furthermore, the corresponding derived 1,3,4-oxadiazole and their thioglycoside as well as their acyclic analogs were prepared. The antimicrobial activity of the prepared compounds was evaluated against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Aspergillus niger and Candida albicans. The dithiohydrazone as well as oxadiazole thiole derivatives, sugar hydrazones and acyclic nucleoside analogs were the highly active compounds.     

Novel bis(5-arylamino-2-oxo-4-thiazolidinylidene)hydrazine derivatives as potential antineoplastic agents

A new series of N,N'-bis(5-arylamino-3-benzyl-2-oxo-4-thiazolidinylidene)hydrazine s has been prepared for potential anticancer activity. The synthesis was achieved by reacting 3-benzylthiazolidin-2-one-4-thione with its 4-hydrazone derivative to give N,N'-bis(3-benzyl-2-oxo-4-thiazolidinylidene)hydrazine, which was subjected to dibromination followed by reaction with various primary aromatic amines. Some compounds were evaluated against leukemia P 388 in the mouse. No significant antitumor activity was observed.     

Zur Synthese des Phaeantharins, 1. Mitt. Syntheseplan für Phaeantharin und Synthese des Bausteines A: 4′,5-Dibrommethyl-2-methoxydiphenylether

On the Synthesis of Phaeantharine, I: Plan of the Synthesis of Phaeantharine and Synthesis of the Unit A: 4′,5-Bis(bromomethyl)-2-methoxydiphenyl Ether A plan for the synthesis of phaeantharine is proposed. The 4′,5-bis(bromomethyl)-2-methoxydiphenyl ether (5) , required for this approach, was prepared in three steps from 4-bromobenzaldehyde (1) and 3-hydroxy-4-methoxybenzaldehyde (2) via the diformyldiphenyl ether 3 and the diol 4 with a total yield of 46%.     

(-)-14-去甲基石杉碱甲的不对称全合成及其乙酰胆碱酯酶抑制活性老年痴呆症药物石杉碱甲类似物研究VI.(-)-14-去甲基石杉碱甲的不对称全合成及其乙酰胆碱酯酶抑制活性

目的(-)-14-去甲基石杉碱甲的合成及其抑制乙酰胆碱酯酶活性研究。方法从β-酮酯3与2-亚甲基-1,3-丙二醇双醋酸酯4在手性膦配体钯催化下,对映选择性的形成双环化合物5,双键移位后得到关键中间体6,进而复结晶富集后,得到光学纯6。经Wittig反应,得双键化合物7,酯基水解后,得到相应酸8。经改良的Curtius重排,产生氨基甲酸酯9。除去保护后,得目标化合物2。结果(-)-14-去甲基石杉碱甲仅是天然(-)-石杉碱甲抑制乙酰胆碱酯酶活性1/8。结论由电鳐乙酰胆碱酯酶与(-)-石杉碱甲复合物X-射线衍射结构分析揭示,14-甲基与酶形成氢键是(-)-石杉碱甲高抑制活性的一个必要基团。     

Isotopic labeling of 2‐desoxoparaherquamide A (PNU‐141962) with deuterium

Modifications of marcfortine A and paraherquamide A led to the discovery of 2‐desoxoparaherquamide A (PNU‐141962, 3 ) which is as active as paraherquamide A and has an improved safety profile. In order to do preclinical studies, we wished to synthesize isotope‐labeled PNU‐141962. This account will describe the synthesis of [CD₃]‐2‐desoxoparaherquamide A ( 4 ). The deuterium product was prepared in anticipation of using a similar synthesis for the preparation of the corresponding ¹⁴C‐ and ³H‐labeled products. Copyright © 2002 John Wiley & Sons, Ltd.     

Synthesis of fluorosugar analogues of 2,5,6-trichloro-1-(beta-D-ribofuranosyl)benzimidazole as antivirals with potentially increased glycosidic bond stability

The metabolic instability in vivo of the glycosidic bond of 2,5, 6-trichloro-1-(beta-D-ribofuranosyl)benzimidazole (TCRB) prompted us to design and synthesize the hitherto unreported fluorinated benzimidazole nucleosides 2,5, 6-trichloro-1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)benzimidazole , 2,5, 6-trichloro-1-(3-deoxy-3-fluoro-beta-D-xylofuranosyl)benzimidazole, and 2-bromo-5, 6-dichloro-1-(2-deoxy-2-fluoro-beta-D-ribofuranosyl)benzimidazole. TCRB was converted into the 2',5'-ditrityl and 3',5'-ditrityl derivatives, which were fluorinated with DAST and deprotected to yield 2,5, 6-trichloro-1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)benzimidazole and 2,5, 6-trichloro-1-(3-deoxy-3-fluoro-beta-D-xylofuranosyl)benzimidazole. The resulting low overall yield (5%) of 2,5, 6-trichloro-1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)benzimidazole encouraged us to develop an alternative route. The heterocycle 2,5, 6-trichlorobenzimidazole was condensed with 1-bromo-3, 5-di-O-benzoyl-2-deoxy-2-fluoro-alpha-D-arabinofuranose to give, after deprotection, 2,5, 6-trichloro-1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)benzimidazole in a 50% overall yield. The 2'-deoxy-2'-fluoro-beta-D-ribofuranosyl compounds were prepared using 2'-deoxy-2'-fluorouridine, N-deoxyribofuranosyl transferase, and 5,6-dichlorobenzimidazole. Functionalization of the C2 position then gave the desired derivatives. Antiviral and cytotoxicity testing revealed that the deoxy fluoro arabinofuranosyl, xylofuranosyl, and ribofuranosyl derivatives were less active against human cytomegalovirus and more cytotoxic than TCRB.     

2-phenylsubstituted-3-hydroxyquinolin-4(1H)-one-carboxamides: Structure-cytotoxic activity relationship study

A structure-activity relationship of some derivatives of 2-phenylsubstituted- 3-hydroxyquinolin-4(1H)-one-7-carboxamides was systematically studied using combinatorial solid-phase synthesis and in vitro cytotoxic activity screening on representative cancer lines. The effect of substituent type in position 2 as well as of the carboxamide group was investigated via synthesis of generic libraries constructed with respect to polarity and bulkiness of appropriate substituents. The process of development afforded a set of compounds with significant cytotoxic activity. Subsequently, corresponding 2-phenylsubstituted-3-hydroxyquinolin-4(1H)-one-6-carboxamides and 2-phenylsubstituted-3-hydroxyquinolin-4(1H)-one-8-carboxamides were prepared to evaluate the influence of the carboxamide group position on the resulting biological activity.     

新型抗肿瘤组蛋白去乙酰化酶抑制剂西达本胺的合成

目的:合成西达本胺{N-(2-氨基-5-氟苯基)4-[N-(吡啶-3-丙烯酰)氨甲基]苯甲酰胺}.方法:以吡啶甲醛为起始原料,通过Knoevenagel反应,制得吡啶丙烯酸,然后以N,N′-碳酰二咪唑(CDI)为催化剂,通过2步酰化反应,合成目标产物.结果:目标产物的产率为29%.结论:本法条件温和,操作简便,适合工业化生产.