The supramolecular material (DB18C6)KC₆₀ is a fulleride with novel magnetic properties.We discover that the magnetic behaviour is directly linked to the orientational ordering of C₆₀ molecule in (DB18C6)KC₆₀ by ¹³C NMR study.

The two-dimensional Nuclear Overhauser Effect Spectroscopy (NOESY)technique was successfully applied to investigate the structure and stereochemistry problems of organic compounds.In this paper, the configurations, conformations and stereochemistry of isomeric compounds 1-6, derivatives of cyclopropane 7, 8 were researched by using NOESY.The structures of compounds 5-8 were simulated by computer molecular modelling, their results were the same as NOESY.

Nuclear magnetic resonance spectroscopy is a powerful technique that provides info rmation on biochemical status and phy siological processes both in vitro and in vivo. The characteristics of energy metabolism and phospholipid pathw ay of mouse S180 sarcoma during growth was studied by ³¹P mag netic resonance spectroscopy (MRS).The results showed that with the increase of tumor volume, (1)Pi and PME peak intensities increase;(2)PCr content decreases and oftend isappeares in the latter phase;(3)β-NTP (usually presenting ATP)peak falls more solwly than PCr peak;(4)PDE shows no constant changes;(5)PCr/Pi and β-NTP/Pi ratios both decrease, and PCr/Pi decreases faster than β-NTP/Pi;(6) PME/β-NTP ratio increases;(7)tumor pH decreases, and is correlated with tumor sizes, PCr/Pi,β-NTP/Pi and (PCr+β-NTP)/Pi ratios.The biology reated to the changes of these parameters was discussed.The spectrum appears to reflect the degree of hyposia of the remaining viable cells, and the metabolic alterations required to sustain ATP synthesis as the oxygen supply diminishes.Increase in the PMEs (mainly PC)is primarily due to the increase of membrane synthesis and cellular proliferation and the increase in PC levels would be accounted for a decrease in the CTP:PC cytidyly ltransferase.

This paper deals with the chemical structure of a benzoyl-substituted xanthone-C-glycoside isolated from the roots of Polygala caudata (Polygalacese)studied by means of NMR spectral analysis.With the aid of 2D NMR techniques (including ¹H-¹H COSY, ¹H-13 CCOSY and HMBC), the full assignments of ¹H and ¹³C NMR spectral data were presented.

Green Tea Polyphenols(GTP) consist of four components, EGCG(-)-epigallocatechin gallate, ECG(-)-epicatechin gallate, EGC(-)epigallocatechin, and EC(-)epicatechin, all of which have the structure of gallate group or pyrogallol group.In alkaline solution, they will be autooxidized to produce different semiquinone free radicals.We investigated the ESR spectroscopy of the pyrogallol GTP, and the four components of GTP respectively, analyzed the possible structure of responsible semiquinone free radical.The ESR signals of the four components are related to the simple unit of pyrogallol, and the ESR signals of GTP are related to their four components according to their respective quantity attribution.

The Tuberostemoenone 1 and Tuberostemonone 2 were isolated from the roots of Stemona tuberosa Tour of the north part of China.In this paper, the 2D NMR gradient inverse techniques(GCOSY, GNOESY, GHM QC and GHMBC)were successfully applied to determine the structures of compounds 1 and 2.Tuberostemoenone 1 is a new alkaloid with novel skeletone.All of the ¹H and ¹³C NMR chemical shifts of compounds 1, 2 were assigned by 2D NMR, and their relative configurations were discussed.The structures of compounds 1, 2 were simulated by computer molecular modelling, their results were the same as 2D NMR.

The characteristics of energy metabolism of mouse brain during acute ischemia was studied using ³¹P NMR.After the ligation of two-sided common carotid artery along with vagus, PCr/Pi、β-ATP/Pi ratios decreased dramatically,and PCr/Pi ratio decreased faster,at the same time brain cells suffered acidosis.Reperfusion after 5min ischemia can partly reverse the injury caused by ischemia.

The phase properties of selective pulses in combination with PFG has been studied theoretically and experimentally.The results show that:for symmetric and antisymmetric shaped pulses, by using selective single PFG spin-echo(SPFGSE) and selective double PFG spin-echo (DPFGSE), pure in-phase magnetization can be obtained in their whole excitation bandwidth.However, for other shaped pulses, the magnetization without phase distortions can only be obtained by using DPFGSE.Moreover, using doubly-selective SPFGSE, neither symmetric (orantisy mmetric) nor non-symmetric shaped pulses can provide pure in-phase magnetization.

The patterns of ¹H and ¹³C chemical shifts in acetylenic compounds (Including acylic、alicylic、conjugative、aromatic and heterocyclic compounds) were system atically discussed.The π-electron circulation model is not reliable.The deformation and variation of density of electron clouds around nuclei is a reasonable model.

All of the carbon signals of ajugasterone C(1)were labeled as compared with the carbon signals of rhapontisterone(2) and ponasterone A(3), respectively.The mistakes, which were made in the belonging of proton signals of this compound in the literature, were corrected by the techniques of ¹H-¹H COSY and ¹³C-¹H COSY.

Isoflavonoids are recognized to possess broad biological activities, such as cardiovascular, estrogenicity and so on.3-Pheny l-4(¹H)-quinolinone derivatives are isosteres of isoflavonoids and they have similar spatial structures.So perhaps they can exhibit similar activities.5- Chloro-6-fluro-3-phenyl-4-(¹H)-quinolinone derivatives and 7-chloro-6-fluro-3-phenyl-4- (¹H)-quinolinone derivatives were desig ned and synthesized at the same time.It's difficult to separate them due to their similar polarity.Only two isomeres (4a, 4b)were separated. 1, 2, 3 were mix tures due to their similar polarity of the two corresponding isomeres.The structures were confirmed by ¹H NMR and the contents of the mixtures were determined by HPLC.

In this paper ¹H-¹H COSY, ¹H-¹³C HMQC and HMBC 2D NMR techniques were used to analyze and assign the ¹H and ¹³C NMR spectra of a new ly synthesized compound 1-(2-carboxy benzoyl)-thiosemicarbazide(H₃L), The ¹H、¹³C NMR spectra of its copper (I) complex [Cu₂(H₃L)₂Cl₂](H₂O)₃ have also been measured.Its coordination property is briefly discussed, and the structure of the complex is suggested.

An NMR Soft pulse Excitation Unit (SEU) with simplicity, economy as well as high performance has been developed.In addition, problems associated to assembling the main parts of the system are discussed in detail.The SEU operates successfully in conjunction with an MSL-300 NMR spectrometer and has been tested for the excitation of ¹H in frequency of about 300MHz.

The structure and the performance of L-band VCO and the resonating cavity are described in this paper.I ts osillating frequency can be tunned in the range of 0.9-1.07GHz, and its output power is more than 10mW.It can operate in scan-frequency mode by using a saw tooth generator.The sample cavity is a square-gap resonator.When a cylindrical sample is inserted into the cavity, the resonating frequency changes only a little.The microwave energy is fed to the cavity by magnetic coupling.While changing the distance between the coils and the cavity the coupling degree can be changed.