新型含咔唑环芳氨基乙酰腙衍生物的合成及其蛋白酪氨酸磷酸酶1B(PTP1B)抑制活性评价

为寻找新型蛋白酪氨酸磷酸酶1B (PTP1B)抑制剂,设计并合成了一系列新型含咔唑环芳氨基乙酰腙衍生物.其结构和构型用IR、~1H NMR、~(13)C NMR和2D NMR(包括~1H-~1H COSY、~1H-~(13)C HMBC和NOESY)谱及元素分析进行了确证.通过对PTP1B抑制活性的测试发现,目标化合物对PTP1B有较强的抑制作用,且大多数化合物的IC_(50)值低于阳性对照药物齐墩果酸,其中N'-(9-辛基咔唑-3-亚甲基)-2-(4-硝基苯氨基)乙酰肼(3t)活性最高,IC_(50)=(2.78±0.04)μmol/L.利用分子对接研究了化合物3t与PTP1B酶的结合情况.     

烟酰胺腺嘌呤二核苷酸(NAD~+)类似物的合成及性质

合成了3种新型结构稳定的烟酰胺腺嘌呤二核苷酸(NAD~+)类似物并通过~1H NMR、~(13)C NMR、~(31)P NMR和HRMS进行了表征。NAD~+类似物经80℃加热24 h后,通过~1H NMR确认其结构稳定;通过循环伏安法(CV)测定了其电化学性质,表明其仍然具有良好的氧化还原性能。     

南海柳珊瑚Menella Spinifera Kukenthal化学成分的研究(一)

从中国南海针小月柳珊瑚(Menella Spinifera Kukenthal)中分离到一种长链甘油醚,其结构经UV、IR、MS、~1H NMR、~(13)C NMR、~1H-~1H COSY以及元素分析确定为3—十八烷氧基—1,2—丙二醇鲨肝醇(Ⅰ)。本文是第一次报导它存在于该种属柳珊瑚之中。 (Ⅰ)的化学结构     

N-氯苯基-2-脱氧-α-D-吡喃核糖亚胺的合成及其晶体结构

在水与甲醇的混合体系中, 2-脱氧-D-核糖与氯代苯胺反应立体选择性地合成了三种N-氯苯基-2-脱氧-α-D-吡喃核糖亚胺(化合物1, 2, 3), 它们的结构经过1H NMR和13C NMR的表征. 将单一构型的N-对氯苯基-2-脱氧-α-D-吡喃核糖亚胺(1)溶于氘代DMSO加入几滴重水, 1H NMR 和13C NMR分析显示1异构化为四种构型的混合物. 培养了化合物1, 2, 3的单晶, 并用X射线衍射法测定了它们的晶体结构. 对晶体结构进行分析, 对反应形成单一构型产物的原因进行了探讨. 并提出了1异构化过程的机理.     

维库溴铵的核磁共振法分析

采用1H NMR,13C NMR,DEPT,H-HCOSY,HSQC,HMBC等多种核磁共振分析方法,确证了维库溴铵的结构,对它的1H和13C NMR谱信号进行了归属,并利用ROESY确定了其相对构型,为其结构鉴定提供了重要依据.     

土壤胡敏酸的^13C核磁共振研究

胡敏酸(HA)是土壤有机质的重要组分,其结构性质与土壤形成和肥力特性有密切关系,长期以来一直是土壤化学研究的难点和重点之一。NMR是研究HA结构的有效手段。自Bar-ton和Schnitzer(1963)首次用~1H NMR研究土壤有机质以来,国外已先后应用~1H、~(13)C NMR和CP-MAS-~(13)C NMR等对土壤及其它来源的HA进行了许多研究,并取得引人注目的进展。但在国内,这方面研究还刚刚开始。本文应用~(13)C NMR方法对东北几种主要耕作土壤以及泥炭和猪粪的HA进行了结构表征,为土壤腐殖酸化学的基础研究提供了资料。     

苯并咪唑萘酰亚胺类化合物的合成与结构确证

本文合成并分离提纯了1位和4位单取代的苯并咪唑萘酰亚胺(NBI)类化合物1~4,对化合物1的紫外-可见光谱、红外光谱、质谱、核磁共振谱(包括1H NMR、13C NMR、DEPT、1H-13C HSQC、1H-13C HMBC、1H-1HCOSY多种NMR技术)进行了详细解析,对其所有的1H和13C NMR信号进行了归属,并使用了GIAO和CSGT两种方法量化计算核磁位移,通过多种波谱学技术确证了化合物的结构。     

膜荚黄芪苷元的结构

从膜荚黄芪的根中分得膜荚黄芪皂苷甲,皂苷乙和皂苷丙.膜荚黄芪皂苷甲是主要成分.药理试验有降压和抗炎作用、皂苷甲经Smith氧化降解得到膜荚黄芪苷元1.用IR,~1HNMR,~(13)C NMR,MS和化学降解证明其结构为1.根据镧系位移试剂的~1H NMR,1的C_(20)和C_(24)的构型分别确定为S和R.     

新喜树碱衍生物的核磁共振谱分析与结构鉴定

以20(S)-喜树碱(CPT)为起始原料,对其进行结构修饰,合成了一种新的喜树碱衍生物CPT-A.并利用1D(~1H、~(13)C和DEPT135)和2D(异核单量子相关谱和异核多碳相关谱)核磁共振(NMR)技术对该化合物进行了结构确定,详细归属了CPT-A~1H和~(13)C NMR谱的化学位移,喜树碱骨架的指认结果与文献报道基本一致,并发现喜树碱骨架6位碳与取代基苯环3’位碳的化学位移相同,谱峰完全重叠,这在~(13)C谱中是不常见的.研究结果可为喜树碱类天然产物的发现和结构鉴定提供NMR数据支持和方法指引.     

Phebalosin的全合成

以间苯二酚和D,L-苹果酸为原料,经Pechmann反应、Reimer-Tiemann反应、Darzens缩合反应及Wittig反应合成了Phebalosin,总收率1.3%,其结构经~1H NMR和~(13)C NMR表征.     

Dications of fluorenylidenes. Contribution of magnetic and structural effects to the antiaromaticity of fluorenylidene dications with cyclic substituents

The antiaromaticity of fluorenylidene dications 1-5, which contain cyclic cationic substituents, has been examined using magnetic criteria, NICS and magnetic susceptibility, and by structural criteria, HOMA. The magnetic criteria, including proton chemical shifts, strongly support the antiaromaticity of the fluorenyl ring system of these dications. HOMA values are a very insensitive measure of structural effects in polycyclic ring systems because they reflect the inability of the fused ring systems to respond to changes in aromaticity/antiaromaticity. Finally, in these systems, the interaction between the ring systems appears to occur primarily through a type of hyperconjugation, as demonstrated by a decrease in the bond lengths for the bonds connecting the ring systems. In conjunction with the evaluation of magnetic effects, the quality of the calculation of (1)H and (13)C NMR shifts was assessed by comparison with experimental data. The calculation of (13)C NMR shifts was excellent in all methods examined, but the quality of (1)H NMR shifts was substantially poorer in calculations using the IGLO method, basis set DZ or II. The CSGT method gives a superior correlation between experimental and calculated (1)H NMR shifts.     

Preparation and NMR characterization of C70H10: cutting a fullerene pi-system in half

Three isomers of C70H10 were prepared by Zn(Cu) reduction of C70. Three chromatographic bands were identified as C70H10 species by MALDI-FT mass spectrometry, and these compounds were isolated by repeated HPLC treatments. The major isomer (2) was characterized by 1H and 13C NMR, while the minor isomers 3-4 were isolated in such small quantities that only 1H NMR analysis was possible. 1H-coupled and 1H-decoupled 13C NMR of 2 established a 7,8,19,26,33,37,45,49,53,63-substitution pattern. This assignment was confirmed by HMBC and DFQ-COSY experiments. This structure is completely reasonable, as we found that 2 results exclusively from reduction of the 7,19,23,27,33,37,44,53-C70H8 that is formed in the course of the Zn(Cu) reduction of C70.     

(s)-多沙唑嗪的核磁共振理论和实验研究

报道了(s)-多沙唑嗪的1H、13C、DEPT、1H-1H COSY等的NMR波谱数据, 并对1H、13C NMR信号进行了指认. (s)-多沙唑嗪分子中含有9个季碳原子, 其中绝大部分通过常规实验的方法难以指认. 应用量子化学规范不变原子轨道(GIAO)的Becke-3-Lee-Yang-Parr(B3LYP)和Hartree-Fock(HF)方法, 分别在6-21G基组下计算了标题化合物的13C NMR化学位移值. 计算结果表明, 理论计算数据与实验结果吻合较好, 可以帮助对(s)-多沙唑嗪季碳原子NMR位移信号进行指认.     

Chemical inequivalence behavior of the protons attached to the same carbon in ethylene-propylene copolymer（EPC）

Six ethylene-propylene copolymer samples with different structural parameters were analyzed by ^1H NMR,^13C NMR and ^1H-^13C COSY in this paper.With the aid of the ^1H-^13C COSY spectra of ethylene-propylene copolymer,the chemical inequivalence behavior of the protons attached to the same carbon in the ethylene-propylene copolymer could be observed. Four basic types of chemical bonds were divided,and two kinds of main conformations were proposed to explain this phenomenon. Based on the calculation of conformation distribution,it can be proved that the explanation of this phenomenon was reasonable.     

取代芳基吡唑和取代芳基异噁唑结构的核磁共振波谱表征

用1 H,13 C NMR和多种二维核磁共振谱表征了本系列化合物的结构,完成了1 H和13 C NMR 谱带的归属,测定了氟原子对各质子和碳原子的偶合常数,探讨了影响偶合常数大小的因素.     

Tautomerism and 1H, 13C and 15N NMR spectral assignments of some nitro derivatives of malonic acid diamide

Because of its reactivity, malonic acid diamide (1) was initially identified as an alternative precursor for the development of a new class of high-density insensitive energetic materials possessing low sensitivity to thermal decomposition and detonation by impact. Nitration of 1 was studied under different conditions and led to three different tautomeric forms (2-4) of nitromalonic acid diamine. Using stronger oxidation conditions the oxadiazole 5 was generated in one step. We report the full 1H, 13C and 15N NMR structural characterization of these compounds in DMSO together with thermal, infrared, mass spectrometric and x-ray analysis. Experimental data obtained for 4 are compatible with an enol-imine form. Our interpretation is consistent with calculated 1H and 13C NMR spectra (ACD).     

南中国海星骨海绵Stelletta sp.中的三萜化合物

最近,我们又从采自广西涠洲岛海域的星骨海绵Stelletta sp.中分离得到3个黄色三萜色素1,2和3(见下式).通过IR,UV,MS和1D NMR,2D NMR等方法测定了它们的结构,并对化合物1的所有C和H进行了指认.同时,通过X射线单晶衍射分析测定了化合物1的立体化学结构.初步的药理实验表明,这3个化合物对P388肿瘤细胞均有很强的抑制活性,ED₅₀值依次为0.01,0.5和1.0μg/mL,提示Stelletta属海绵中的这类三萜具有很好的药用开发前景.     

Molecular structure, IR and NMR spectra of 2,6 distyrylpyridine by density functional theory and ab initio Hartree-Fock calculations

Vibrational frequencies and gauge including atomic orbital (GIAO) 13C NMR and 1H NMR chemical shift values of 2,6 distyrylpyridine (C21H17N) in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (B3LYP) with 6-31G(d) basis set. These methods are proposed as a tool to be applied in the structural characterization of 2,6 distyrylpyridine (C21H17N). The title compound has C2v point group, thus providing useful support in the interpretation of experimental IR data. In addition, obtained results were related to the linear correlation plot of experimental 13C NMR, 1H NMR chemical shifts values and IR data.     

巴比妥酸与芳香醛的固相反应研究

固相有机化学反应作为绿色化学的重要组成部分是近年来发展起来的新领域 [1,2 ] .固相有机化学反应中 ,反应物分子受晶格的控制 ,运动状态受到很大限制 ,因此表现出比溶液更高的反应效率及反应选择性[3～ 6] .巴比妥酸具有生理活性 ,且有较高的化学反应活性 ,尤其是 C5位的氢 ,由于受相邻两个羰基的吸电子作用而具有较强的酸性 ( p H=4.0 0 ) .因此 ,巴比妥酸与芳香醛易发生 Knoevenagel型缩合反应 ,生成 C5取代的衍生物 - 5 -亚烃基巴比妥酸 .这类缩合反应在溶液中很容易发生 [7,8] ,近年来又发现在蒙脱土 KSF存在下 [9] 及无载体条件下…