Medical chemistry is one of the important basic medicines.Faced with the rapid development of education,Medical chemical education reform or innovation should also keep vigorous.In this paper,we discuss how to innovate and improve the quality and effect of experiment in the process of medical chemistry experiment and lay a solid foundation for continued study.

A newly developed topological vector of atom Y_C, equilibrium electro-negativity of atom q_e, molecular structural information parameter[N_H~i(i=α, β)] and γ calibration parameter were used to describe the local chemical microenvironment of 63 acyclic alcoholic compounds. Quantitative structural spectrum relationships (QSSR) was systematically made on relationship between ~(13)C NMR chemical shifts of 353 carbon atoms and their molecular structure descriptors. By partial least square regression(PLS), the statistical results indicated that the model correlation coefficient and standard error were 0.9915 and 2.4827, respectively. And the average absolute error was only 2.01×10~(-6) between the calculated and experimental chemical shifts for 353 carbon atoms. To validate the estimation stability for internal samples and the predictive capability for external samples of resulting models, leave-molecule-out(LMO) cross validation(CV) and external validation were performed. Compared with the reported result, not only the number of descriptors employed in this study was much fewer, but also the calculation was much easier.

OBJECTIVETo study the chemical constituents from the antioxidant fraction of Neo-Taraxacum siphonathum.

METHODVarious chromatographic techniques were used to isolate and purify the constituents. The structures were elucidated on the basis of chemical evidence and spectral analysis.

RESULTTen compounds were isolated and identified from Neo-T. siphonathum, caffeic acid (1), chlorogenic acid (2), quercetin (3), luteolin (4), quercetin-3-O-beta-D-glucopyranoside (5), quercetin-3-O-alpha-D-arabinofuranoside (6), quercetin-3-O-alpha-D-arabinopyranoside (7), luteolin-7-O-beta-D-glucopyranoside (8), beta-sitosterol (9) and daucosterol (10).

CONCLUSIONCompounds 1-10 were isolated from this plant for the first time.

Caffeic Acids ; chemistry ; isolation & purification ; Chlorogenic Acid ; chemistry ; isolation & purification ; Glucosides ; chemistry ; isolation & purification ; Luteolin ; chemistry ; isolation & purification ; Magnetic Resonance Spectroscopy ; Quercetin ; chemistry ; isolation & purification ; Sitosterols ; chemistry ; isolation & purification ; Taraxacum ; chemistry

Objective:To investigate the clinical value of three-dimensional arterial spin marker imaging(3D-ASL) for evaluating collateral circulation compensatory status in patients with cerebral infarction.Methods:A total of 24 patients with cerebral infarction who were treated at Wenzhou Hospital of Traditional Chinese Medicine Affiliated to Zhejiang University of Chinese Medicine from September 2017 to January 2019 were examined by 1.5-T high-field MR scanner.The changes of cerebral blood flow(CBF) between the infarcted area and the contralateral normal area were compared when the labeled delay time(PLD)=1.5s and PLD=2.5s, and the patients were divided into the group with strong collateral circulation compensation and the group with weak collateral circulation compensation according to the difference in lesion area measured by 3D-ASL(PLD=1.5s and 2.5s). The changes of national institutes of health stroke scale(NIHSS) score and Bathel index at admission and 15 days after admission were compared.Results:3D-ASL measurement of PLD=1.5s showed that the CBF value in the infarcted area was (33.70±20.83)mL/(100g×min), which was significantly lower than that in the contralateral normal area(PLD=1.5s)[(49.93±13.13)mL/(100g×min)]( t=3.229, P<0.05). When PLD=2.5s, ASL measurement results showed that the CBF value in the infarcted area increased significantly[(58.26±23.50)mL/(100g×min) vs.(33.70±20.83)mL/(100g×min)]( t=3.831, P<0.05), and the CBF value in the contralateral normal area also increased significantly[(68.29±14.03)mL/(100g×min) vs.(49.93±13.13)mL/(100g×min)]( t=4.681, P<0.05). At this time, the CBF value in the infarcted area was still significantly lower than that in the contralateral normal area[(58.26±23.50)mL/(100g×min) vs.(68.29±14.03)mL/(100g×min)]( t=1.795, P<0.05). On the day of admission, the BI index of patients in the weak collateral circulation compensation group(12 cases) was significantly higher than that in the strong collateral circulation compensation group(12 cases)[(90.42±10.50) vs.(67.92±27.57)]( t=2.642, P<0.05), and the NIHSS score was significantly lower than that in the strong collateral circulation compensation group[(1.25±1.01) vs.(3.83±3.62)]( t=2.378, P<0.05). After 15 d of admission, there were no significant differences in BI index and NIHSS score between the two groups(all P>0.05). Conclusion:3D-ASL with different delay time can effectively and intuitively reflect collateral circulation compensation of patients with cerebral infarction, and it has very important reference value for the evaluation of patients' disease and the formulation of clinical treatment plan.