脱氢松香酸甲酯类衍生物的合成

以脱氢松香酸甲酯为原料, 经溴代、硝化、还原、重氮化等步骤合成了6种12位取代的脱氢松香酸甲酯衍生物, 研究了12位上不同取代基对它们紫外、荧光性质的影响; 然后再分别以得到的12-氯脱氢松香酸甲酯和12-溴脱氢松香酸甲酯为起始物, 经双硝化、氧化、脱异丙基硝化等步骤合成了一系列重要的脱氢松香酸甲酯卤代硝化衍生物, 并对12-氯脱氢松香酸甲酯、12-溴-13,14-二硝基脱氢松香酸甲酯的单晶进行了X射线衍射表征.     

一些含氮杂环的脱氢松香酸甲酯衍生物的合成

以歧化松香为原料,将其纯化得到脱氢松香酸,用硫酸二甲酯酯化后,通过12位溴代、7位氧化、脱异丙基硝化等步骤,得到了3个重要的中间体.该3个中间体分别经过亲核取代、还原关环反应后,得到了一些脱氢松香酸甲酯含氮杂环衍生物;产物结构经红外光谱、核磁共振谱、质谱和元素分析进行了表征.     

离子液体中12-苯甲酰基脱氢松香酸甲酯的合成

以离子液体[bmim]Br/AlCl3作为绿色反应介质,通过脱氢松香酸甲酯芳环上的Friedel-Crafts酰基化反应,合成了12-苯甲酰基脱氢松香酸甲酯,最佳合成条件为:脱氧松香酸甲酯、[bmim]Br、AlCl3、苯甲酰氯的摩尔比1:4:8:8,反应温度40℃,反应时间2h.用IR、MS、NMR和元素分析等方法对目标产物进行了分析和表征.结果表明,该合成方法具有反应条件温和、反应时间短及环境友好等优点.     

脱氢松香酸酯氧化反应混合产物的二维核磁共振谱分析

采用二维核磁共振波谱中全相关谱(TOCSY)成功区分了脱氢松香酸甲酯(Ⅰ)和7-羰基脱氢松香酸甲酯(Ⅱ)混合产物中各化合物的氢信号,分析鉴定了混合物中两种甲酯结构,并对混合物氢信号进行了归属。该方法简便易行,适合快速判断反应历程并区分相近结构的混合物。     

3,4-二氨基呋咱基氧化呋咱的制备及晶体结构研究

首次通过3-氨基-4-氯肟基呋咱在热作用下脱HCl、[4 2]关环反应制备了新型呋咱(氧化呋咱)类含能化合物3,4-二氨基呋咱基氧化呋咱(DAFF),并培养出了DAFF单晶.用X射线单晶衍射、元素分析和红外光谱对其分子结构进行了表征.测试结果表明:DAFF晶体属三斜晶系,空间群P1,a=0.6400(4)nm,b=1.0609(8)nm,c=1.4634(7)nm,α=83.53(5)°,β=87.27(4)°,γ=77.74(5)°,V=0.9645(11)nm3,Z=4,Dc=1.737g?cm-3,F(000)=512,μ(MoKα)=0.149mm-1;R1=0.0568,wR2=0.1137.DAFF分子不共面,三环面扭曲,面间夹角为27.18(1.99)°和30.48(2.07)°,晶体中存在分子内和分子间氢键.     

新型脱氢松香基苯并咪唑类衍生物的合成及其氯离子识别性能

以脱氢松香酸甲酯为原料, 经溴代、双硝化、还原、关环等步骤合成了五个新型脱氢松香基苯并咪唑类衍生物(6a～6e). 其结构用1H NMR和13C NMR进行了确证. 对6a～6e进行了阴离子识别研究, 并对其结构与氯离子识别能力的关系进行了讨论.     

3,4-双(3',5'-二硝基苯-1'-基)氧化呋咱的合成

设计并合成了新化合物3,4-双(3',5'-二硝基苯-1'-基)氧化呋咱(4).以苯甲腈为起始原料,经加成、重氮化、分子间二聚得到3,4-二苯基氧化呋咱(3),3经HNO3/H2SO4硝化合成了4,其结构经1H NMR,IR和元素分析表征;初步考察了加成、重氮化、缩合环化、硝化等反应的主要影响因素,确定了适宜的反应条件.     

3,4-二硝基呋咱的合成

以乙二醛为起始原料,常压法制备3,4-二氨基呋咱(DAF),收率56.4%,纯度98.4%.采用"一步法"氧化工艺,以50%H2O2为氧化剂,H2SO4起始浓度56.9%,于35℃反应3.5 h,由DAF合成了3,4-二硝基呋咱(DNF),收率62.5%,纯度99.8%.DNF的结构经13C NMR,IR,MS和元素分析表征.讨论了DAF氧化成DNF的反应历程.     

5(4H)-吡啶酮并氧化呋咱及其核苷衍生物的合成及结构表征

设计了一个新化合物——5(4H)-吡啶酮并氧化呋咱(4H,5H-[1,2,5]噁二唑[3,4-b]吡啶-5-酮-1-氧化物),对它的合成方法及四乙酰核糖核苷衍生物的合成进行了研究.合成产物及中间体经1HNMR、质谱和元素分析进行了结构鉴定.     

3,4-双(3,′5′-二硝基苯-1′-基)氧化呋咱的合成

设计并合成了新化合物3,4-双（3′,5′-二硝基苯-1′-基）氧化呋咱（4）。以苯甲腈为起始原料,经加成、重氮化、分子间二聚得到3,4-二苯基氧化呋咱（3）,3经HNO3／H2SO。硝化合成了4,其结构经^1H NMR,IR和元素分析表征;初步考察了加成、重氮化、缩合环化、硝化等反应的主要影响因素,确定了适宜的反应条件。     

EPA甲酯和DHA甲酯标准样品的制备和结构解析

从鱼油中分离制备得到二十碳五烯酸（EPA）甲酯和二十二碳六烯酸（DHA）甲酯,采用红外光谱、质谱、核磁共振波谱等手段对EPA甲酯和DHA甲酯的结构进行表征,提供了不饱和脂肪酸甲酯标准物质研制基础。样品的红外光谱（IR）、质谱（MS）、核磁共振谱图（1HNMR、13CNMR）所给出的结构信息与EPA甲酯和DHA甲酯的化学结构式相符,并通过DEPT谱和I3C-1H COSY化学位移相关谱（HMBC）对各共振峰进行了指认,样品的谱图数据与文献报道基本一致。     

四萜Methyl Sartortuoate 的分离和NMR归属

从采自海南岛三亚的扭曲肉芝软珊瑚Sarcophyton tortuosum中分离得到3个新四萜和1个已知四萜methyl sar-tortuoate (1). 利用HMQC, ¹H-¹HCOSY, HMBC等二维NMR方法首次对methyl sartortuoate (1)的所有¹H, ¹³C NMR信号进行了完全的归属.     

E/Z-焦脱镁叶绿酸-a 甲酯131-酮肟的合成及其烷(酰)基化反应

以焦脱镁叶绿酸-a 甲酯(MPP-a)为起始原料,通过E环羰基与盐酸羟胺反应,生成Z/E顺反结构的焦脱镁叶绿酸-a 甲酯酮肟异构体,分离后与酰卤和卤代烷反应,分别生成Z或者E型O-烷酰基酮肟和O-烷基酮肟.所合成新的二氢卟吩衍生物均经UV, IR, 1H NMR, 13C NMR及元素分析证实其结构.     

Synthesis of methyl 12-benzoyldehydroabietate in ionic liquid

In the presence of the ionic liquid [bmim]Br/AlCl₃ as green reaction medium, methyl 12-benzoyldehydroabietate was synthesized through Friedel-Crafts acylation reactions on the aromatic ring of methyl dehydroabietate. The optimum synthetic conditions of the target product were found to be as follows: molar ratio of methyl dehydroabietate to [bmim]Br to AlCl₃ to benzoyl chloride 1:4:8:8, reaction temperature 40°C, reaction time 2 h. The target product was analyzed and characterized by means of IR, MS, NMR and elemental analysis. The results show that this novel method has the advantages of mild condition, short reaction time and environmental benignity. __________ Translated from Chemistry, 2008, 71(2): 138–143     

Magic-Angle-Pulse Driven Separation of Degenerate 1H Transitions in Methyl Groups of Proteins: Application to Studies of Methyl Axis Dynamics

Dynamics of protein side chains is one of the principal determinants of conformational entropy in protein structures and molecular recognition events. We describe NMR experiments that rely on the use of magic-angle pulses for efficient isolation of degenerate ¹H transitions of the I=3/2 manifold of ¹³CH₃ methyl groups, and serve as ‘building blocks’ for the measurement of transverse spin relaxation rates of the fast- and slow-relaxing ¹H transitions – the primary quantitative reporters of methyl axis dynamics in selectively {¹³CH₃}-methyl-labelled, highly deuterated proteins. The magic-angle-pulse driven experiments are technically simpler and, in the absence of relaxation, predicted to be 2.3-fold more sensitive than previously developed analogous schemes. Validation of the methodology on a sample of {¹³CH₃}-labeled ubiquitin demonstrates quantitative agreement between order parameters of methyl three-fold symmetry axis obtained with magic-angle-pulse driven experiments and other established NMR techniques, paving the way for studies of methyl axis dynamics in human DNAJB6b chaperone, a protein that undergoes exchange with high-molecular-weight oligomeric species.     

Complete assignment of 1H and 13C NMR spectra of some alpha-arylthio and alpha-arylsulfonyl substituted N-methoxy-N-methyl propionamides

The complete assignments of the 1H and 13C NMR spectra of the some alpha-arylthio and alpha-arylsulfonyl substituted N-methoxy-N-methyl propionamides, bearing methoxy, methyl, chloro, and nitro as substituents at the phenyl ring are reported.     

Anti-babesial compounds from Curcuma xanthorrhiza

Anti-babesial ingredients, (12R)- and (12S)-12,13-dihydro-12,13-dihydroxyxanthorrhizols, were isolated from Curcuma xanthorrhiza. The structures were established by the extensive NMR techniques. The assignments of (1)H NMR data of (12R)-12,13-dihydro-12,13-dihydroxyxanthorrhizol was revised, and (12S)-12,13-dihydro-12,13-dihydroxyxanthorrhizol was isolated as a pure form for the first time. The IC(50) of the active compounds were compared with that of commercial drug, diminazene aceturate (Ganaseg). IC(50) values of Ganaseg, (12R)-, and (12S)-12,13-dihydro-12,13-dihydroxyxanthorrhizols were 0.6 microg mL(-1), 8.3 microg mL(-1) and 11.6 microg mL(-1), respectively.     

乙基二茂铁与乙酰丙酸甲酯的缩合反应

以多聚磷酸-浓硫酸-甲醇为催化剂和环已烷为溶剂,由乙基二茂铁与乙酰丙酸甲酯缩合合成4,4-双（乙基二茂铁基）成酸甲酯,转化率73%,产率84%。正交实验法获得的适宜反应条件：乙基二茂铁55mmol,乙酰丙酸甲酯75mmol,浓硫酸3.0mL,环已烷20mL,甲醇11mL。通过元素分析、IR、^1H NMR和^13C NMR确证了缩合产物的结构。     

The effect of an unsymmetric branched branch on the 13C NMR chemical shifts of main chain carbons in polyethylene

The ¹³C NMR spectra of copolymers of ethylene with 4‐methyl‐1‐hexene and 4‐methyl‐1‐pentene, respectively, were compared. The 4‐methyl‐1‐hexene/ethylene copolymer, which contains an unsymmetric 2‐methylbutyl branch, exhibits two distinct ¹³C NMR peaks for each of the pairwise methylenes spaced one, two, and three carbons from the backbone methine. The chemical shift differences for these pairwise methylenes are 57.4 Hz, 18.7 Hz, and 4.3 Hz, respectively, with chemical shift differences decreasing with increasing distance from the asymmetric carbon. The frequency differences for carbons farther from the branch were not distinguishable. The magnitude of the chemical shift difference also varies with temperature, with the first and second methylene carbon chemical shift differences decreasing with increasing temperature. The third carbon is almost unaffected by temperature variations. In contrast, the 4‐methyl‐1‐pentene/ethylene copolymer exhibits a single peak for each of the pairs of methylenes in the branch's vicinity. This is the first reported observation of a branched branch affecting the chemical shifts of main chain carbons in polyethylene containing short chain branches. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1210–1213, 2000     

南海黄蜂海绵中系列长链甲基酮成分分析

从中国南海海绵Spheciospongia Vagabunda乙酸乙酯萃取部分中分离出一组混合物,应用^13HNMR,^13CNMR,H-HCOSY和GC／MS等光谱分析技术对它们的结构进行了分析,主要为一些长链甲基酮化合物。共鉴定出二十四碳烯-2-酮异构体、二十四碳二烯-2-酮和二十四碳烯-2-酮等14种化合物,其中4种化合物的双键位置有待于进一步确定。