代位
- 与 代位 相关的网络例句 [注:此内容来源于网络,仅供参考]
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METHODS: Based on the antitumor activity and structural feature of 8-chloroadenosine and retinoic acid, modifications were made at positions 5′ and 8,substituted cinnamoyl and benzoyl groups were bound at 8 position through amido and ester bonds, sulfonation and nitrosation at 5′-OH and its direct chlorination were conducted.
对腺苷的8位和8-Cl-腺苷的糖环羟基进行了结构改造,以酰胺键和酯键在腺苷的8位连接了具共轭基团的肉桂酰基和苯甲酰基,得到腺苷的维甲类似物;对8-Cl-腺苷的5′-羟基进行了甲磺酰化,硝基化以及氯代反应,得到了它的衍生物。
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Quinazolin-4(3H)-ones(1) were conveniently synthesized from anthranilic acids and amidines,which could be chloridized with POCl_3 to obtain 4-chloroquinazolines (2).The reaction of 2 and 1H-pyrazol-3-amine would give two types of products.In the presence of acid or base,the C-N bond would be formed between the 4-position carbon of 2 and the NH_2 of 1H-pyrazol-3-amine.While the C-N bond between the 4-position carbon of 2 and the NH of 1H-pyrazol-3-amine would be formed when Pd catalyst was utilized.
以邻氨基苯甲酸类化合物和脒为原料,可方便地获得喹唑啉-4(3H)-酮类产物(1),1经POCl_3氯化可到4-氯代喹唑啉化合物(2)。2与3-氨基-1H-吡唑化合物反应可得到两种类型的产物,在酸、碱条件下2的4位碳和3-氨基-1H-吡唑化合物的NH_2发生C-N成键反应;在Pd催化条件下,2的4位碳则和3-氨基-1H-吡唑化合物的环内NH发生C-N成键反应。
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The bay area has no substituent and has electron-withdrawing groups,such as bromine atom,cyano-group and 4-formyl phenoxy group compounds have strong absorption in 525 nm,when excitated them,they have strong yellow and salmon pink luminescence bettwen 538 and 566 nm.When introduce electron-donating substituents,such as phenoxy group,morpholinyl,piperidinyl and n-butylamino group,the absorption bathochromic shift while the electron-donating ability is improved,bettwen 536 and 692 nm have strong absorption,reach to the near-infrared region. When excitated them,only the phenoxy group compound has strong salmon pink luminescence in 572 nm,the others have no fluorescence.
其中,港湾位无取代的以及含吸电基团(—Br、—CN、对甲酰基苯氧基)化合物在525 nm左右处均有很强的吸收ε>10~4M~(-1cm~(-1),当光激发时,港湾位无取代、溴代和氰基取代物发出538~547 nm的强烈黄色荧光,对甲酰基苯氧基取代物则发出566 nm的强烈橙红色荧光;含供电基团(苯氧基、吗啉基、哌啶基、正丁氨基)化合物随着供电子能力的增强,吸收发生红移,在536~692 nm处均有很强的吸收ε>10~4M~(-1cm~(-1),达到了近红外区,当光激发时,只有苯氧基取代物发出572 nm的强烈橙红色荧光,而含氮供电基取代物均发生了荧光淬灭。
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Direct competitions of intramolecular C - H insertions into benzylic C - H and 4-nitroor 4-methoxy substituted benzylic C - H of methyl 2-diazo-3-oxo-6-(4-substituted phenyl)-4-(2-phenylethyl)hexanoate 44a and 44b catalyzed by Rh-mediated carbenoid were alsoinvestigated, and the relative reactivities obtained by compound 44a or 44b were comparableto those obtained by indirect method.
此外,还研究了Rh催化分解下,对位硝基取代或甲氧基取代的4-(2-苯基乙基)-6-(4-取代苯基)-2-重氮基-3-氧代己酸甲酯44a、44b苯甲位C-H插入反应的相对速率,与化合物47a和47f得到的结果比较,数据平行。
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The spectral data suggest that intramolecular carbonyl oxygen to tin coordination in 1 is existent and is not allowedin order to accommodate two and three bidentate dithiocarbamate ligands in 3 and 4 respectively.
波谱数据表明化合物1和2存在着分子内羰基氧原子对锡原子的配位,而在化合物3和4中这一配位则被两个或三个双齿二硫代氨基甲酸配体所替代。
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Urine VMA level is a useful marker to detect extra-adrenal pheochromocytoma and CT scan is the most reliable in localizing the lesions.131-MIBG scintigraphy is of great value for the localiza-tion and quantitative for extrarenal pheochromocytoma with high sensitivity and accuracy.It may be also used as a therapeutic method.
VMA及血、尿儿茶酚胺是定性诊断异位嗜铬细胞瘤的主要依据,CT诊断定位准确、131碘-间位碘代苄胍(131I-MIBG)定位准确、敏感性高,且可作为治疗措施。
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In the presence of catalytic rhodium acetate, ethyl 2-diazo-3-oxo-per fluoroalkanoates, reacted readily with nitriles to give a series of 5-fluoroalkyl substituted 1, 3oxazoles with high regio-selectivity through a metal carbenoid intermediate. The reactions of carbenoids with noncyclic vinyl ethers or cyclic vinyl ethers afforded dihydrofuroates in good to excellent yields. Interestingly, only vinyl C-H insertion compound was obtained concerning of the reaction of carbenoids with 2, 5dimethylfuran due to the steric hindrance of methyl group
醋酸铑分解2-重氮-3-氧代-全氟羧酸乙酯形成的金属卡宾作为1,3-偶极体,可以与一系列芳基或烷基取代的腈反应,高度区域选择性地生成一系列4-乙氧羰基-5-氟烷基取代的噁唑化合物;也可以与富电子的链状和环状的烯基醚反应,以优良的产率得到一系列氟烷基取代的二氢呋喃类化合物;而与2,5-二甲基呋喃的反应,由于甲基的位阻作用,只得到金属卡宾对呋喃3-位烯基碳氢键插入产物。
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Deming took over as chief executive in late1994,succeeding two nonfamily chief executives and becoming the first third-generation family member to run the company.
戴明继两位非家族老总之后,于1994年年底接任首席执行官,从而成为第一位管理该公司的第三代家族成员。
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A 43-year-old jobless woman, who never dreamed of becoming a lawmaker, was elected to Japan's House of Representatives, local media reported. A Democratic Party of Japan upper house lawmaker presciently asked Kayoko Isogai, who has held mostly non-regular jobs since finishing university, to run as a candidate at the bottom of a local ballot and she got the nod from voters.
日本媒体日前披露,不久前当选国会议员的矶谷香代子是个普通的钟点工,大学毕业以后一直没有固定工作,更毫无当选的思想准备。43岁的她此前被一位民主党参议员推荐参加竞选,排在名古屋东海地区候选人中的最末位。
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Anteac had addressed herself sharply to the heavyset officer commanding the Fish Speaker escort, a glowering woman with low brows and the muscles of a manual laborer.
安缇克曾严厉地向一位指挥鱼之代言者护卫的体格魁梧的官员抗议,她是位眉毛低垂、有着体力劳动者的肌肉、瞪着双眼的女人。
- 推荐网络例句
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For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether
年美国个人破产法的一个改动使得破产登记急速下降,而后引起了信用卡大规模的亏损。
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Eph. 4:23 And that you be renewed in the spirit of your mind
弗四23 而在你们心思的灵里得以更新
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Lao Qiu is the Chairman of China Qiuyang Translation Group and the head master of the Confucius School. He has committed himself to the research and promotion of the classics of China.
老秋先生为中国秋阳翻译集团的董事长和孔子商学院的院长,致力于国学的研究和推广。