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111.
The first synthesis of 3-alkyl-5-hydroxycyclohex-2-enones is reported. An intramolecular cyclization by means of an aldolic addition/sulfinate elimination tandem reactions, performed under mild basic conditions was the key step. 相似文献
112.
焦测序技术及其在遗传分析中的应用 总被引:10,自引:3,他引:7
焦测序技术是一种新的实时DNA测序技术。它在DNA聚合酶、三磷酸腺苷硫酸化酶、荧光素酶和三磷酸腺苷双磷酸酶4种酶的协同作用下,使引物延伸聚合脱氧核糖核酸(dNTP)释放焦磷酸盐(PP i)、PP i转换三磷酸腺苷(ATP)、ATP产生荧光信号与dNTP和ATP的降解等化学反应偶联起来,检测结果准确可靠。本文综述了焦测序技术的基本原理、操作步骤和它在单核苷酸多态性(SNP)研究、微生物的分型鉴定和基因甲基化检测等遗传分析中的应用,并对焦测序技术的发展作了展望。 相似文献
113.
Tai Te Wu 《Applied biochemistry and biotechnology》1994,47(2-3):107-118
Theoretical analyses of amino acid and nucleotide sequences of immunoglobulins have provided a unique approach to the understanding
of structure and function of antibodies. Variability plots unambiguously identified that the antibody-combining site is formed
by six short complementarity determining regions (CDRs), three each from light and heavy chains. Since three-dimensional (3-D)
foldings of framework regions (FRs) are similar among different antibodies, the 3-D configurations of CDRs from a specific
antibody can be predicted based on their amino acid sequences. The resulting structure forms a compact surface that fits the
antigen molecule tightly. The third CDR of the heavy chain (CDRH3), which is coded by the D-minigene together with the N-
and/or P-segments, appears to play a unique role in fine fitting between antibody and antigen molecules. In order to maintain
biological activities, the grafting of mouse CDRs onto human FRs should closely match the human FR amino acid sequences with
the original mouse antibody. Similarities between human and mouse FR sequences that have been preserved for over 20 million
years of evolution can be a useful tool in humanizing mouse antibodies. 相似文献
114.
José G. Aguirre-De Paz Davir González-Calderón Aydeé Fuentes-Benítes Carlos González-Romero 《Tetrahedron letters》2018,59(18):1760-1762
The exploration of azide-enolate cycloaddition in the synthesis of novel Rufinamide analogs is reported for the first time. A very simple procedure involving the use of β-ketonitriles as dipolarophiles afforded 5-aril/heteroayl Rufinamide derivatives in two steps. 相似文献
115.
Bachir Douara Yannick J. Esvan Elisabeth Pereira Francis Giraud Yulia L. Volodina Dmitry N. Kaluzhny Alexander A. Shtil Fabrice Anizon Pascale Moreau 《Tetrahedron》2018,74(8):892-901
Pyrazole analogs of the staurosporine aglycon K252c were recently described as potent inhibitors of the three Pim protein kinase isoforms. To evaluate the impact of the introduction of a sugar moiety on the biological activities of this heterocyclic scaffold, four new glucosylated pyrazole analogs of K252c were synthesized. Their biological evaluation demonstrated that most active compounds 11 and 19 substituted by a β-d-glucosyl moiety at N12 or N13 positions exhibited antiproliferative activities toward HCT116 cells. 相似文献
116.
Tricyclic analogs 2a and 8 were prepared by four-step routes. The key step was an intermolecular hetero Diels-Alder reaction involving a quinone methide. 相似文献
117.
2-(Per-O-acetyl-β-d-glycopyranosyl)-1,4-dimethoxybenzenes led to C-glycosyl-hydroquinones suitable for preparing C-glycosylated analogs of vitamin E, having the sugar moiety free or acetylated. 相似文献
118.
A systematic approach evaluating template-directed ligation reactions has now resulted in a simple outline for a two-stage replication cycle. This cycle builds on an efficient method for reading the information encoded in DNA into an amplified translation product. It is further demonstrated that the translation product strand is capable of catalyzing the synthesis of the original DNA strand. We propose that this cycle represents just one of many possible solutions; other chemical ligation or polymerization reactions could be accommodated with different templates. In that context, a new template, derived by modest changes to the DNA backbone, has been developed and has been shown to hybridize under reaction conditions different than those accessible to DNA. Therefore, the conceptual groundwork has been laid for extending this approach to encoding and reading stored information in molecules other than the natural biopolymers at the densities found in biology. 相似文献
119.
Ionic Liquids as Mobile Phase Additives for Separation of Nucleotides in High-Performance Liquid Chromatography 总被引:1,自引:0,他引:1
Ionic liquids are a type of salts that are liquid at low temperature (<100℃). Because of their some special properties, they have been widely used as new “green solvents” for many chemical reactions and liquid-liquid extraction in the past several years. In this paper, a new method for the separation of nucleotides is developed and the essential feature of the method is that 1-alkyl-3-methylimidazolium salts are used as mobile phase additives, resulting in a baseline separation of nucleotides without need of gradient elution and need of organic solvent addition as currently used in RP-HPLC. This study shows the potential application of ionic liquids as mobile phase additives in reversed-phase liquid chromatograohy. 相似文献
120.
A new synthetic strategy for hydroxy-epoxy eicosanoids formed through the lipoxygenase pathway is developed. It makes use
of a single synthon of the central functionalized fragment of the target molecules, namely racemic (E)-ClCH2C≡CCHOHCH=CHCH2OBz. Elongation of the carbon chain of the synthon by successive condensations at both ends altenatively with hept-1-yne and
hex-5-ynoic acid followed by enantioselective double bond epoxidation and partial hydrogenation of the triple bonds resulted
in the syntheses of hepoxilins B3, their potential 8-lipoxygenase analogs, or their enantiomers, depending on the sequence of carbon chain elongations and
the chirality of the epoxidation controller used.
For Part 6, see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1229–1238, June, 1998. 相似文献