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16,17α-环氧-5α-和5β-孕甾-3β-醇-20-酮(1,2)用诺卡氏菌脱氢分别得到4,5,6,7和8,5,6,7四个化合物,其中16,17α-环氧-⊿4-孕甾烯-3,20-双酮(5)是主要产物.1和2分别用节杆菌脱氢时则均得到两个20α-羟基的不饱和化合物15和16,其中⊿1,4-双酮16是主要产物.16,17α-环氧-16β-甲基-5α-⊿9(11)-孕甾烯-3β-醇-20-酮(3)用诺卡氏菌脱氢可得到12,13,14三个化合物,其中16,17α-环氧-16β-甲基-⊿4,9(11)-孕甾二烯-3,20-双酮(13)是主要产物.综上所述,5α和5β甾族化合物用诺卡氏菌脱氢主要脱去C4,5两个氢原子形成⊿4-烯-3-酮化合物,而采用节杆菌可使Cl,2和C4,5位同时脱氢形成⊿1,4-双烯-3-酮化合物. 相似文献
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以2-氨基吡嗪为原料,经5步反应(两次NBS溴代反应,两次Suzuki 交叉偶联反应和HCl作用下的缩合反应),合成了6个新型的C8-位芳杂环取代的腔肠素衍生物,其结构经1H NMR和13C NMR表征。 相似文献
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以三嵌段共聚物P123为模板剂, 在酸性条件下通过1,2-三乙氧基硅基乙烷(BTESE)和3-含氧缩水甘油基-丙基-三甲氧基硅烷(GPTMS)共水解缩聚合成环氧基修饰的周期性介孔氧化硅(PMOs), 以修饰后的PMOs为载体对漆酶进行固定化, 研究了环氧基修饰对固定化酶稳定性的影响. 通过XRD、TEM、固态NMR和N2吸附等手段表征材料的修饰效果、孔结构以及漆酶的固定化. 结果表明, 修饰后的材料保持良好的孔结构, 环氧基的修饰有利于提高固定化酶的活力, 基于环氧基修饰PMOs的固定化酶具有较高稳定性. 相似文献
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N-三甲硅甲基苯甲醛亚胺为非稳定型亚甲胺基叶立德前体,在磷酸催化下与取代噁唑烷酮烯烃经1,3-偶极环加成反应合成了10个具有cis-trans立体结构的新型2,3,4-三取代四氢吡咯-3-羧酸衍生物(3a~3j),收率65%~75%,其结构经1H NMR, 13C NMR和HR-MS表征。3b的立体结构经X-单晶衍射确证。 相似文献
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以3,5-二溴-1-{3-(十二烷氧基)-2-[(十二烷氧基)甲基]丙氧基}苯和2-甲基-3-丁炔-2-醇为原料,经选择性Sonogashira偶联反应,Sonogashira偶联反应和去硅保护基反应制得中间体--3-乙炔基-5-(3-甲基-3-羟基)-丁炔基-1-(3-十二烷氧基)-2-{[(十二烷氧基)甲基]丙氧基}苯(6); 6经改良的Glaser偶联反应(CuI为催化剂,Et3N为溶剂)合成了一个新型的丁二炔衍生物(1)。 6与2,2′-[(2,5-二碘-1,4-亚苯基)双(氧基)]双(四氢-2H-吡喃)经Sonogashira偶联,脱 THP保护基和改良的Glaser偶联反应合成了一个新型的丁二炔衍生物(2)。中间体,1和2的结构经1H NMR, 13C NMR和MALDI-TOF-MS表征。 相似文献
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1,2-双(四甲基环戊二烯基)四甲基二硅烷与正丁基锂作用生成(四甲基二硅撑)双(四甲基环戊二烯基负离子盐),后者随即与六碳基钼反应形成1,1'-(四甲基二硅撑)双(四甲基环戊二烯基铝负离子盐)-(Me2SiSiMe2)[Me4CpMo(CO)3-Li+]2(I),I与冰醋酸作用,随即分别与CCl4,NBS及I2反应,生成相应的铝卤化合物(Me2SiSiMe2)[Me4CpMo(CO)3X]2[X=Cl(1),Br(2),I(3)].I与CH3I反应,在钼原子上发生烃基化,得到产物(Me2SiSiMe2)[Me4CpMo(CO)3Me]2(4);I与单质I2直接反应,生成脱硅桥产物Me4Cp(CO)>3I(5).经元素分析、IR及1HNMR表征了化合物1-5的结构。 相似文献
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Siva Lakshmi Devi A Srinivasa Rao Y Suresh Y Yogeswar Reddy M Jyothi G Rajababu B Prasad VS Umamaheswar Rao V 《Magnetic resonance in chemistry : MRC》2007,45(5):424-429
We report the complete (1)H and (13)C NMR assignment of impurities of six Lopinavir (2S)-N-[(2S, 4S, 5S)-5-{[2-(2,6-dimethylphenoxy)acetyl]amino}-4-hydroxy-1,6-diphenyl hexan-2-yl]-3-methyl-2-(2-oxo-1,3-diazinan-1-yl)butan- amide. Two of the impurities are regioisomers and GCOSY used to differentiate the two structures. The spectral assignments for all six impurities were achieved by concerted application of one and two-dimensional NMR techniques ((1)H NMR, (13)C NMR, DEPT, GCOSY, GHSQC and GHMBC). 相似文献
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用超声辐射催化方法 ,合成了C2 3 H19N2 SF3 O2 Zn(1) Zn(2 )C8H5SF3 O2 双核锌大杂环配合物 ,经IR ,1HNMR ,13 CNMR ,MS和元素分析表征 .通过波谱分析表明 ,Zn(1)采取dsp3 杂化与 1,2 二氮 5 ,8 二氧 3 ,4,10 ,11 双 (苯并 )环十四 13 三氟甲基 1 噻吩配位 ,Zn(2 )采取sp2 杂化与 1′ 噻吩 3′ 三氟甲基 1′ ,3′ 二丙酮配位 ,形成双核锌 (II)树状型配合物 相似文献
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Katritzky AR Akhmedov NG Abdel-Fattah AA Wang M Rostek CJ Maender OW 《Magnetic resonance in chemistry : MRC》2004,42(5):424-435
Nucleophilic addition of alkyl- and benzylthiols to benzoquinone diimine (1) gave the corresponding 3-alkylthio- or 3-benzylthio-1,4-phenylenediamines (2-5). However, addition of aryl- or heteroarylthiols to 1 formed 2-arylthio- or 2-heteroarylthio-1,4-phenylenediamines (6-14). The structures of 2-14, obtained in 55-91% yields, were confirmed in CDCl3 or DMSO-d6 solution using 1D (NOE difference, coupled 13C NMR spectra, APT and DEPT) and 2D NMR techniques [DQCOSY, NOESY, HETCOR and heteronuclear multiple bond coherence (HMBC)] that resulted in unambiguous proton and carbon NMR resonance assignments. The substituent-induced 13C NMR chemical shift differences were calculated in 2-14 relative to carbon atoms in the model compound N1-(1,3-dimethylbutyl)-N4-phenyl-1,4-phenylenediamine (DMBPPD) (15) (a reduced form of benzoquinone diimine). 相似文献
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以3-硝基-2-氨基苯甲酸甲酯为原料,经三氟乙酰化、N-烷基化和脱保护反应制得坎地沙坦中间体2-{[(2'-氰基联苯基-4-基)甲基]氨基}-3-硝基苯甲酸甲酯,其结构经~1H NMR,~(13)C NMR和MS(ESI)确证。 相似文献
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High-resolution liquid- and solid-state 119Sn NMR spectroscopy was used to study the bonding environment in the series of monomeric, two-coordinate Sn(II) compounds of formula Sn(X)C6H3-2,6-Trip2 (X = Cl, Cr(eta 5-C5H5)(CO)3, t-Bu, Sn(Me)2C6H3-2,6-Trip2; Trip = C6H2-2,4,6-i-Pr3). The trends in the principal components of the chemical shift tensor extracted from the solid-state NMR data were consistent with the structures determined by X-ray crystallography. Furthermore, the spectra for the first three compounds displayed the largest 119Sn NMR chemical shift anisotropies (up to 3798 ppm) of any tin compound for which data are currently available. Relaxation time based calculations for the dimetallic compound 2,6-Trip2H3C6Sn-Sn(Me)2C6H3-2,6-Trip2 suggests that the chemical shift anisotropy for the two-coordinate tin center may be as much as ca. 7098 ppm, which is as broad as the 1 MHz bandwidth of the NMR spectrometer. 相似文献
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Highly dense nitrogen-rich ionic compounds are potential high-performance energetic materials for use in military and industrial venues. Guanazinium salts with promising energetic anions and a family of energetic salts based on nitrogen-rich cations and the 6-nitroamino-2,4-diazido[1,3,5]triazine anion (NADAT) were prepared and fully characterized by elemental analysis, IR spectroscopy, (1)H NMR and (13)C NMR spectroscopy, and differential scanning calorimetry (DSC). The crystal structures of neutral NADAT (2) and its biguanidinium salt 5 were determined by single-crystal X-ray diffraction (2: orthorhombic, Pnma; 5: monoclinic, P2(1)). Additionally, the isomerization behavior of 2 in solution was investigated by proton-decoupled (13)C and (15)N NMR spectroscopy. All the new salts exhibit desirable physical properties, such as relatively high densities (1.63-1.78 g cm(-3)) and moderate thermal stabilities (T(d) = 130-196 °C for 3-10 and 209-257 °C for 11-15). Theoretical performance calculations (Gaussian 03 and Cheetah 5.0) gave detonation pressures and velocities for the ionic compounds 3-15 in the range of 21.0-30.3 GPa and 7675-9048 m s(-1), respectively, which makes them competitive energetic materials. 相似文献
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An 8-(13)C-labeled guanosine derivative, 2',3',5'-O-tert-butyldimethylsilyl-N-tert-butyldimethylsilyl-8-(13)C-guanosine, was synthesized and its photosensitized oxidation with singlet oxygen carried out below -100 degrees C. Two transient intermediates that decompose directly to the final major product 5 and CO(2) were detected by (13)C NMR between -100 and -43 degrees C. The two intermediates are carbamic acids based on (13)C NMR and 2D NMR (HMQC, HMBC) spectra and the formation of final product 5 and of 8-CO(2). No endoperoxide intermediate could be detected by low-temperature NMR spectroscopy even at -100 degrees C. A reaction mechanism is proposed involving initial [4 + 2] cycloaddition of singlet oxygen to the imidazole ring to form an unstable endoperoxide, subsequent rearrangement of the endoperoxide to a dioxirane, and decomposition of the dioxirane to the two observed intermediates. Both oxygen atoms of CO(2) are derived from a single oxygen molecule, which strongly supports a dioxirane structure for the precursor of the two observed intermediates. The distribution of products estimated by (13)C NMR accounts for all the (13)C-containing products in the reaction mixture. 相似文献
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鸦胆子化学成份的研究 II.鸦胆子苦素E-葡萄糖苷 总被引:1,自引:0,他引:1
A new quassinoid glucoside, yadanzigan (1a), has been isolated from Brucea javanica (L) Merr. 1a has formula C26H38O14(M+574), m.p. 243-245C, (α)D^2^3 60.0 (c. 1.70, H2O). The structure has been established as brucein E-2-β-D-glucopyranoside by enzymatic hydrolysis of 1a and elemental analyses, ^1H NMR, ^1^3C NMR and mass spectral analyses of 1a and its aglycone 2a. 相似文献
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The β-blockers are important drugs and decades of clinical experience proved their high medical status. However, to the best of our knowledge, there is no complete assignment of (1)H and (13)C NMR resonances of popular representatives: acebutolol, alpenolol, pindolol, timolol and propranolol and the published NMR data on carvedilol and atenolol are incorrect. Therefore, (1)H and (13)C NMR spectroscopy was applied for the characterization of a series of β-adrenolytics: carvedilol (1), pindolol (2), alprenolol (3), acebutolol (4), atenolol (5), propranolol (6) and timolol (7). Two-dimensional NMR experiments (COSY, HMQC, HMBC, NOESY) allowed the unequivocal assignment of (1)H and (13)C spectra for solution (DMSO-d(6) ). Salts and bases can be easily distinguished based on (13)C chemical shifts which are within 65.0-65.5 ppm (OC2) and 46.9-47.0 (NC3) for hydrochlorides and larger, ca. 68.4 ppm (OC2) and 50.3-52.6 (NC3) for bases. NMR data of 1-7 should be included in pharmacopoeias. 相似文献