This note describes the hindered rotation isomerism of steroidal alkaloid epi-pachysamine A (la, 1b). By DEPT technique, ¹H, ¹³C HETCOR, ¹H, ¹H NOESY; the ¹³C NMR data of cpi-pachysamine A as a double hindered rotation isomer were assigned as Table 1.

Based on the atomic coordinates determinated by X-ray diffraction and the principal values of ¹³C-NMR chemical shifts, we introduced an approach to calculate the chemical shifts of orientated PET. The direction of drawing axis of PET was parallel to the direction of magnetic field. The calculated results fit the experimental data very well. Thus, we get the conclusion that the main direction of molecular chain is parallel to the drawing axis.

The ¹H and ¹³C NMR spectra of acetylate of strychnolactone (Ib) were assigned with J-resolved, ¹H-¹H COSY and ¹³C-¹H COSY data. Its stable and dominant conformation in solution was also discussed.

The ¹³C-NMR spectra of eight unknown amino acids, oligo peptide-estrogenic steroids have been studied. The features of the spectra peaks were discussed. The formation of these two kinds of new compounds was confirmed on the basis of ¹³C-NMR.

The ¹H and ¹³C NMR spectra of fibroin from He Nan B. mori and Liao Ning A. pernyi (yellow and artificial white cocoon) in trifluoroacetic acid were recorded on Bruker AM-500 NMR spectrometer. The NMR spectral lines of main amino acid residues in silk protein have been obtained. The results show that the amount of amino acids in B. mori and A. pernyi is different, but the NMR spectrum of fibroin from A. pernyi yellow cocoon is similar to that of artificial white cocoon.

Electron spin resonance spectra were observed during the enzymatic reduction of 2, 4, 6-Trinitrotoluene (TNT) respectively by rat hepatic and lens microsomes or mitochondria in anaerobic conditions at room temperature. With the evidence of ESR simulation of computer, the spectra indicated that TNT anion radical was present and its parameters are:g=2.0048±.0005, A (Npara)=1.215 mT, A (Northo)=0.800±.010 mT, A (H)=0.122±.020 mT, with 20mW of microwave power and 100 kHz of modulation frequency. The hyperfine splitting constants of TNT anion radical implied that the unpaired electron density in TNT was mainly distributed in para-nitro group.

8, 2'-o-cyclo-Ara-A is the key intermediate for the synthesis of Ara-A. There is a few reports on the NMR of this compound, only H-1' chemical shifts and coupling constants were reported, but no ¹³C-NMR data reported. ¹H and ¹³C NMR spectra of 8, 2'-o-cyclo-Ara-A were assigned by ¹H-¹H COSY, ¹³C-¹H COSY and NOE-DIFFERENCE techniques. The conformation of sugar ring was further confirmed.

¹H-and ¹³C-NMR spectra of hydrogenated polybutadiene and hydrogenated styrene-butadiene copolymers were examined in this paper on the JEOL FX-90Q and Bruker AM-300 NMR spectrometers. Well resolved spectra and new structural information have been obtained. The kind of CH or CH₂ of each peak is determined by the DEPT technique. Chemical shifts of relevant carbon atoms in the triads were calculated using Grant-Paul and Lindeman-Adams empirical methods. The effect of phenyl group on α, β and γ carbon atoms has been considered. New assignments of 28 groups of peaks in aliphatic carbon atom region are given and confirmed by the correlation between the peak intensity and the composition of the model copolymers. The calculated chemical shift values are essentially consistent with experimental results.

In this paper, the results of the solvent effect of crystal violet and leuco crystal violet by ¹H NMR are reported.
In strong organic acids, all the methyl peaks shift to downficld. In the substituted benzene solvents, all the methyl peaks shift to upfield. There arc linear relationships between the methyl chemical shifts of CV and LCV and the Hammett and the modified Hammett substituent constant. The use of electronic mobility and the linear relationship between the substituent constant a and a-are discussed.

With the method of ESR saturation power point we have detected the hair of 573 cases of healthy, pulmonary cancer, oesophageal cancer, as well as silicosis, pulmonary tuberculosis related with pulmonary cancer, and cardiovascular disease, mean while compared with their clinical diagnosis. The results show that the positive rate is 1.69%, 85.42%, 90.48%, 20.0%, 27.27% and 0% respectively. There is an obvious distinction between pulmonary cancer, oesophageal cancer and healthy person (P<0.001). ESR saturation power point elevates sharply after treatment of pulmonary cancer, 71.43% are between 7.9 to 24.0 (mW), after treatment of oesophageal cancer, 71.23% are between 7.9 to 19.9 (mW). All patients with cardiovascular disease were examined to be negative, i. e above 10.0 (mW).

This article deals with the ¹H NMR of N, N-dimethyl formamide (DMF) in a mixed solvent of benzene and carbon tetrachloride. It has been found that the chemical shifts of the resonance absorption lines of the two methyl groups in N, N-dimethyl formamide (DMF) and that of benzene in the mixed solvent move upficld gradually, as the mole fraction of benzene in the mixed solvent increases. And the rates of upficld shifts of the resonance absorption lines of the two methyl groups are different. △δ of α-CH₃ is larger than that of β-CH₃.The chemical shifts of the two methyl groups in DMF and benzene in the mixed solvent can be schemed with a linear equation (δ=A + BX), where X is the mole fraction of benzene in the mixed solvent. The correlation coefficients R are approximately equal to-1.

It is difficult to distinguish the configuration of z, z¹-6, 6¹,7.3a¹-diligustilide by 1D-NMR due to its complexity. In this paper, the configurations of this compound have been elucidated by 400 MHz ¹H-¹H COSY and ¹H-¹H NOESY. In addition, from 2D-NMR experimental result, its structure and configuration were unambiguously determined.

¹³C NMR of a series of cis-Pt (diphos) X₂ complexes was studied. The results showed that X ligand and R alkyl have considerable effect on the chemical shift of bridge carbon (C₁). The existance of conformational isomers of some compounds was confirmed and the conformational characteristics of platinum complexes was discussed.

We presented a NMR probe for single crystal measurements in the article. The probe employed a single coil double tuned both for proton and a heteronucleus, whose resonant frequencies covered a range from 90MHz to 110MHz, therefore it could perform crosspolarization (CP) experiments associated with high power proton decoupling. A simple but effective goniometer mechanism ensured the sample to rotate precisely about the three axes which were orthogonal with one another. This probe was applied for the measurements of chemical shift tensors in single crystals. We also presented, for an example, the results for DGO (2NH₂CH₂COOH. H₂C₂O₄)in the work.

Currently, the approximate spin-density, Tl-, T2-weighted density MR Imaging are widely used in Clinical MRI. But unfortunately, because the density deferences between human soft tissues and tumors are not large enough, it's difficult to use these methods to distinguish different kinds of tumors. On the other hand, a large number of publications about " in vitro" NMR relaxation time measurments since 1970's have shown, that the NMR relaxation time of tumors are obviously different from that of human tissues, and it can be used to distinguish tumors.
The saturation recovery multi spin-echo method has been used to carry out the pure Spin-Lattice Relaxation Time Imaging. Using this method, one can also measure the in vivo Tl value point by point and the mean value of a special region, by means of ROI special software. Before doing the imaging experiments, the computer simulation of the physical-mathematical model has been done on VAX-11/785 and Micro VAX-Ⅱ systems.

The self-diffusion coefficients of polystyrene (PS) dissolved in CCl₄ and in CCl₄+D₃COD at θ condition were measured by the spin echo pulsed field gradient method. The dependence of the measured self-diffusion coefficient on concentration and molecular weight was proved basically to follow the scaling law of the rcptation model by de-Gennes.