Reactions of 4-[4′-(1′,3′-Diphenylpyrazolyl)methylene]-2-phenyl-5-oxo-2-oxazoline with grignard reagents and diazoalkanes

The title compound reacts with two moles of Grignard reagents with 1,2-addition to give the alcohol 4 , and/or the oxazoline 5 , or with 1,4-addition to give the amino ketone 6 . A reaction mechanism is proposed. Diazomethane is always added to the exocyclic double bond in 1 , but diphenyldiazomethane, in addition, replaces the carbonyl-oxygen by a benzhydrylidene group to give compound 9 .     

化学交换精馏法分离同位素硼-10研究进展

综述了化学交换精馏法分离同位素硼-10的技术进展。在介绍化学交换精馏法分离同位素硼-10原理的基础上,分析了目前工业化过程分离同位素硼-10存在的问题,指出新的络合剂-硝基甲烷(CH3NO2)、丙酮(Acetone)、甲基异丁基酮(MIBK)、二异丁基酮(DIBK)等用于从三氟化硼分离硼-10具有更高的分离系数,形成的络合物具有更好的稳定性,其中CH3NO2是现有同位素硼-10分离工艺过程较为理想的替代络合剂。     

席弗酰腙碱类化合物的合成及其表征

酰腙类化合物是由酰肼与醛或酮缩合而成的一类Schiff碱类化合物,具有独特的生物活性和较强的的抑菌、抗病毒和抗肿瘤的生物活性。本文以甲基丙烯酸甲酯、乙酰乙酸乙酯为反应物,分别与水合肼反应,生成了甲基丙烯酰肼与二乙酰肼,进一步缩合,得到未见报道的环戊酮甲基丙烯酰腙和丙酮二乙酰腙。     

精馏与化学交换法分离硼同位素中液相络合剂的研究

采用苯甲醚、硝基甲烷、丙酮、甲基异丁基甲酮4种络合剂分别与三氟化硼合成出了4种络合物体系。对这4种络合物体系性能进行了实验研究与分析,为中试及工业化生产高丰度硼10同位素提供设计依据。通过分析认为硝基甲烷和丙酮分离系数较高,在性能上优于目前常用的苯甲醚系统,更适宜于应用在硼同位素的分离生产过程中,但是否在工业生产中更能减少能耗,缩短生产周期,降低成本还需要更进一步详细的工业生产经济分析对照。     

利用环己酮精馏残渣合成酮树脂

以环己酮精馏残渣和甲醛为原料,用复合酸作催化剂,通过均苯四甲酸酐改性,合成一种新的酮树脂.本文介绍了合成的工艺条件,这种树脂具有较好的综合性能,具有较广的应用前景.     

3,4-二氢-4-(1-哌啶甲基)-5H-1-苯并氧杂-5-酮盐酸盐的合成及其生物活性研究

α,β-不饱和环戊酮的Mannich碱和α,β-不饱和环己酮的Mannich碱具有显著的抗炎活性,为了寻求新的具有抗炎活性的环酮类化合物,设计了3,4-二氢-4-(1-哌啶甲基)-5H-1-苯并氧杂-5-酮盐酸盐作为目标化合物。以苯酚、γ-丁内酯、甲醛和哌啶等原料合成了目标化合物,并利用熔点、红外光谱、核磁共振氢谱等手段确定了其结构。采用二甲苯致小鼠耳肿胀法,测定了该化合物的抗炎活性,实验结果表明在200mg/kg剂量下该化合物对二甲苯所致小鼠耳肿胀的抑制率为54.5%。采用Born's比浊法测定了该化合物的抗血小板聚集活性,实验结果表明该化合物的抗血小板聚集活性比噻氯匹啶强约23倍。     

Design,Synthesis, and Evaluation of Lipopeptide Conjugates of Mercaptoundecahydrododecaborate for Boron Neutron Capture Therapy

We developed new ¹⁰B carriers for boron neutron capture therapy (BNCT) that can effectively transport and accumulate boron clusters into cells. These carriers consist of a lipopeptide, mercaptoundecahydrododecaborate (BSH), and a disulfide linker. The carriers were conceived according to the structure of pepducin, a membrane-penetrating lipopeptide targeting protease-activated receptor 1 (PAR1). To improve the membrane permeability of BSH, the structure was optimized using various lipopeptides possessing different peptides and lipid moieties. These synthesized lipopeptides were conjugated with BSH and evaluated for intracellular uptake using T98G glioblastoma cells. Among them, the most effectively incorporated and accumulated in the cells was compound 5 a , which contains a peptide of 13 residues derived from the intracellular third loop of PAR1 and a palmitoyl group. For further improvement of ¹⁰B accumulation in cells, the introduction of an amine linker was investigated; intracellular uptake similar to that of 5 a was observed for compound 14 , which has a piperazine linker. Both compounds 5 a and 14 showed a stronger radiosensitizing effect than BSH along on T98G cells under mixed-neutron beam irradiation. The results demonstrate that lipopeptide conjugation is effective for enhancing intracellular delivery and accumulation of BSH and improving the cytotoxic effect of BNCT.     

反-5-丙基-2-(4'-溴-苯基)-四氢吡喃的合成

以对溴苯甲酸为起始原料,经酰化后生成酰氯,酰氯与N,O-二甲基羟胺盐酸盐反应生成酰胺,再与氯乙烯基镁反应生成α,β不饱和酮。同时,正戊醛与二正丙胺反应生成烯胺。α,β不饱和酮与烯胺经迈克尔加成反应生成分子内醛酮,分子内醛酮经关环反应、乙醇重结晶可得到色谱纯度99.5%以上的反-5-丙基-2-(4'-溴-苯基)-四氢吡喃。     

Stereoselective Total Synthesis of (±)-Ptilocaulin and its 7-Epimer. A Strategy Based On the Use of an Intramolecular Nitrile Oxide Olefin Cycloaddition (INOC) Reaction

A stereoselective total synthesis of (±)-ptilocaulin 1 , an antimicrobial anticancer agent as well as of its 7-epimer 23 is described. The strategy involves an aldol condensation of the dilithio dianion of the Z-aldoxime ( 13 ) with a ketone 6 to produce 11 and the stereospecific intramolecular cycloaddition of the nitrile oxide 5 , generated in situ from 11. The resulting isoxazoline 4 was converted to hydroxy ketone 3 which serves as a starting point for introduction of the fourth stereocenter at C-7. Lithium in ethylamine reduction of 3 produces stereospecifically the 7β-methyl compound which leads to ptilocaulin 1 , while catalytic hydrogenation of 3 introduces the 7α-methyl substituent and finally 7-epiptilocaulin 23. H- and C NMR analysis permits differentiation between isomers of intermediates. When, in the last step of the synthesis of 1 or 23 from 19 or 22 and guanidine, a higher temperature (>130 °C) was applied, an interesting disproportionation to aminopyrimidine 25 or 28 and cyclic guanidine 24 or 27 was observed.     

Effects of monomer impurities on the emulsion polymerization of chloroprene and properties of polychloroprene. I. Effect of methyl vinyl ketone

The influences of small amounts (up to 2%) of methyl vinyl ketone in chloroprene on properties of polychloroprene and kinetics of the emulsion polymerization of chloroprene with mercaptans as regulators has been studied. Methyl vinyl ketone causes a substantial increase in molecular weight of polymer, which results in increased viscosity, gel formation, lowered plasticity of polymer, deterioration of processability, decreased tensile strength, and high modulus of vulcanizates. Methyl vinyl ketone interferes with the regulation of molecular weight by both primary and tertiary dodecylmercaptan; some differences are due to lower reactivity of tertiary dodecylmercaptan. In the presence of diisopropyl xanthogene disulfide as a molecular weight regulator the polychloroprene properties are not affected by methyl vinyl ketone. All changes in polymer properties have been proved to be caused by the addition reaction of dodecylmercaptan on methyl vinyl ketone, yielding 1-dodecylthiobutan-3-one. This compound itself has no influence on the polymerization of chloroprene. Methyl vinyl ketone has a marked promoting effect on polymerization rates, which accounts for its high reactivity and solubility in the water phase. A fast polymerization of methyl vinyl ketone takes place in the water phase of emulsion polymerization system simultaneously with the reaction of methyl vinyl ketone with dodecylmercaptan.     

Inactivation of glucosamine-6-phosphate synthase by N3-oxoacyl derivatives of L-2,3-diaminopropanoic acid

N(3)-Oxoacyl derivatives of L-2,3-diaminopropanoic acid 1-4, containing either an epoxide group or a conjugated double bond system, inactivate Saccharomyces cerevisiae glucosamine-6-phosphate (GlcN-6-P) synthase in a time- and concentration dependent manner. The results of kinetics studies on inactivation suggested a biphasic course, with formation of the enzyme-ligand complex preceding irreversible modification of the enzyme. The examined compounds differed markedly in their affinity to the enzyme active site. Inhibitors containing a phenyl ketone moiety bound much more strongly than their methyl ketone counterparts. The molecular mechanism of enzyme inactivation by phenyl ketone compounds 1 and 3 was elucidated by using a stepwise approach with 2D NMR, MS and UV-visible spectroscopy. A substituted thiazine derivative was identified as the final product of a model reaction between an epoxide compound, 1, and L-cysteine ethyl ester (CEE); and the respective cyclic product, found as a result of reaction between 1 and CGIF tetrapeptide, was identical to the N-terminal fragment of GlcN-6-P synthase. On the other hand, the reaction of a double-bond-containing compound, 3, with CEE, CGIF and GlcN-6-P synthase led to the formation of a C-S bond, without any further conversion or rearrangement. Molecular mechanisms of the reactions studied are proposed.     

泰拉菌素的合成工艺改进

以阿奇霉素A(Ⅰ)为原料,经苄氧羰酰氯保护2'位羟基得到保护的阿奇霉素A(Ⅱ),然后经Albright-Goldman方法氧化4″位羟基得到Cbz保护的酮(Ⅲ),酮通过Wittig-Horner反应得到保护的烯(Ⅳ),烯经双氧水氧化得到保护的环氧化合物(Ⅴ),保护的环氧化合物在Pd/C催化下脱保护得到脱保护的环氧化合物(Ⅵ),脱保护的环氧化合物与正丙胺反应开环得到泰拉菌素粗品,粗品泰拉菌素成磷酸盐纯化,最后解析得到泰拉菌素(Ⅶ),总收率为42.0%,经HPLC测定w(Ⅶ)=98.0%。该法改进了文献合成方法,不需采用极低温反应。     

A New Indole Synthesis Promoted by Metal Triflates

A new synthesis of 4- and 7-carbon-substituted indoles is described. The overall sequence involves the addition of a nitrile oxide to 1 carboethoxy-2-(or 3-) allylpyrrole, hydrogenation of the intermediate isoxazoline to β-hydroxy ketone and cyclization of the ketol using magnesium or zinc triflate to the substituted indole. This new indole-forming strategy can also accommodate the introduction of oxygen functionality into the indole 6-position. Possible mechanistic aspects of the reaction are detailed.     

Mercury(II)‐Catalyzed Synthesis of Spiro[4.5]decatrienediones from Allenyl Ketones and Comparison with Silver(I)‐, Palladium(II)‐ and Brønsted Acid‐Catalyzed Reactions

The allenyl p‐methoxybenzyl ketone 3a and allenyl p‐siloxybenzyl ketones 6b selectively delivered three different products with three different transition metal‐catalysts. With Hg(II)‐catalysts a spiro[4.5]decene 9 , with Ag(I)‐catalysts a 2‐substituted furan ( 10/11 ) and with Pd(II)‐catalysts a 2,4‐disubstituted furan ( 8/12 ) was formed. Only with perchloric acid the intermolecular addition of water to the allene, leading to 1,3‐dicarbonyl compounds 7 , was observed. While with the corresponding allenyl o‐methoxybenzyl ketone 3b the Ag(I)‐ and Pd(II)‐catalysts provided the expected products, the mercury‐catalyst led to a new and interesting side‐product rac‐ 17 which combined both the furan moiety and the spiro[4.5]decene moiety. Efforts to prepare allenyl hydroxybenzyl ketones failed, in one case a small amount of a 5H‐benzo[b]oxepin‐4‐one 21 was isolated. It also was not possible to extend the spirocyclization to allenyl p‐siloxyphenyl ketone 6a or allenyl 2‐(p‐siloxyphenyl)ethyl ketone 6c .     

GPC calibration for poly(methyl acrylate)

Summary Electrophylic vinyl reagents can be reacted with a protonated tertiary amine supported by a polymeric chain. We determined the mechanism of this addition in the case of vinyl methyl ketone and poly (4 vinyl pyridinium bromide). The first step is the addition of the vinyl compound on the tertiary amine, then protonation of the intermediate species occurs. The velocity constant at 268 K is 0.087 1. mole^–1. mn^–1 and the activation energy is 10 kcal.mole^–1.     

Plasma developable photoresist containing electronic excitation energy quenching system

A dry developable negative working resist composition comprised of poly(methyl isopropenyl ketone) (PMIPK) and 4-methyl-2,6-di(4′-azido-benzylidene) cyclohexanone-1 was examined. The main photochemical product formed in the resist pattern was found to be a secondary amine which crosslinks PMIPK. Post-annealing forms a hydrogen-bonded product which shows a powerful electronic excitation energy quenching effect. The quencher is more powerful than the aromatic compound arising from the azide by post-annealing only. The residual resist thickness of the negative pattern is about 80 percent of the initial thickness of the coating in spite of all the azide compound remaining in the resist coating. The obtained dry developed resist pattern has a high dry etch resistance. Etchings of Si and SiO₂ were performed by plasma and reactive ion etching, respectively.     

一种新型β-二酮化合物的合成及结构表征

通过Claisen缩合反应,在强碱叔丁醇钾的作用下,把长链端烯引入到β-二酮分子中,合成了一种新型的含长链端烯的β-二酮化合物——13-十四碳烯-2,4-二酮(BSH),并通过红外光谱、核磁共振、质谱和元素分析对其结构进行了确证。这种β-二酮化合物在氯仿溶液中主要以烯醇形式存在。该化合物可作为配体用于有机电致发光配合物的合成。     

1-(反式-4-烷基环己基)-苯基-2-含氟苯基取代乙炔类液晶的合成与性能

以烷基环己酮和溴苯为起始原料,通过格氏反应、氢解、傅克酰化、维格特氧化、乙酰氯加成、脱氯化氢等9步反应,合成了末端为4-F、3,4-F,F、3-F及3,5-F,F基团的4个1-(反式-4-烷基环己基)-苯基-2-含氟苯基取代乙炔类液晶化合物,总收率为6.7%~7.6%,产物结构经IR,1HNMR确认。其中氯代二芳基取代乙烯(Ⅷ)的合成采用简便的乙酰氯加成反应得到,使反应缩短了两步。化合物添加到液晶的基础配方中,能同时改善基础配方的低温和高温性能,提高其双折射率,增加响应速度。     

A novel electroneutral anion host based on organoboron betaines

Host-guest binding of anions in organic solvents may find attractive applications in ion sensing and transport, if the host can extract the negatively charged guest species from its solvation sphere. The most powerful means to dismantle the anionic guest from solvent molecules that is required for selective binding is to provide positive charges in the host compound. They have to be counterbalanced by negatively charged subsites in order to conserve electroneutrality, but must avoid collapse into ion pairing with the cationic sites. According to this concept the cage compound 3 was constructed by attachment of anionic tetraphenylborate moieties to the parent macrotricyclic amine 1 . The betainic product 3 was shown to be soluble in water-immiscible dipolar organic solvents like propylene carbonate and formed inclusion complexes with chloride and bromide in the gas phase as well as in solution.     

从沙棘中提取黄酮类化合物的研究

概述了国内外对沙棘资源的开发利用研究状况，分析了黄酮类化合物的结构和药用价值，论述了从沙棘中提取黄酮类化合物的可行性工艺流程及其用途。利用沙棘叶和沙棘油废渣提取黄酮类化合物，原料来源充足易得、成本低，同时可以减少“三废”污染。