| Objective 1. Salidroside is a phenylpropanoid glycoside isolated from Rhodiola rosea L., a traditional Chinese medicinal plant, and has displayed a broad spectrum of pharmacological properties, such as resisting anoxia, microwave radiation and fatigue, improving oxygen lack, and postponing ageing and so on. In recent years, salidroside has been used in such special posts as diver, astronaut, pilot and mountaineer to enhance the ability for survival in adverse environment. Furthermore, many researches revealed that it has the activities of preventing cardiovascular disease and resisting cancers. On the other hand, the wild resource of which was on the edge of exhaustion. Up to now,the report of salidroside modified through the glycosly moiety or aryl ring was very few either in domestic or in overseas.Therefore,in this paper salidroside and its analogues were synthesised in order to discover compound which had more efficacy.2. To observe the protective effects of salidroside and its analogues on hypoglycemia and serum limitation-induced injury in PC12 cells.3. To investigate the free radical scavenging activities of 20 different glucosides by 2, 2-diphenyl-1-picrylhydrazyl (DPPH·).Methods 1. This paper attempted to prepare salidroside and its analogues with O-acetobrome-sugar(glucose and galactose) as donor which synthesised from inexpensive sugars(glucose and galactose), the different substituted of benzyl alcohol and phenylethyl alcohol as aglycone.The entire reaction route included the building of monosaccharide donor moiety and the synthesis of glucoside.This work mainly involved the protection of hydroxyl acetylated,the activation of anomeric carbon,the formation of the bond of glucoside, deacetylation, debenzylation. And the formation mechanism of glucosyl bond was simply discussed.2. PC12 cells were cultured under hypoglycemia and serum limitation environment to establish a hypoglycemia and serum limitation model in PC12 cell line. MTT assay was used to detect the celluar viability after incubation.3. Cultured PC12 cells were pre-incubated with different concentrations(60μmol/L, 300μmol/L, 1000μmol/L) of salidroside and its analogues for 24h, after which hypoglycemia and serum limitation was applied to the cells for 24h, phase contrast microscope observation and MTT assay were used to identify the effect of salidroside and its analogues against hypoglycemia and serum limitation induced injury.4. Spectrum scanning was used to analyze the characteristic absorbance of DPPH·. Microplate quantification of DPPH·was used to quantify antioxidative capability (AC) of salidroside and its analogues . AC represents the amount (μg) of DPPH·scavenged by each milliliter of the samples.Results 1. 20 target compounds were synthesised.2. The results of MTT assay indicated that hypoglycemia and serum limitation could evoke significant cytotoxicity to the cultured PC12 cells, with the incubation time increased, the cell viability decreased.3. Morphalogical observation and MTT assay showed that salidroside and its analogues could protect cultured PC12 cells against hypoglycemia and serum limitation-induced cell viability decrease.4. The highest absorbance of DPPH·was shown on microplate reader at wavelength of 517 nm. The higher the sample concentrations used, the higher the free radical-scavenging effect. The absorbance decreased as the result of DPPH·color change from purple to yellow. The IC50 (μg DPPH·/ml) of the 20 glucosides was afforded.Conclusions 1. The structures of all the compounds that we synthesized were confirmed by IR,1H NMR and elemental analysis, the configuration of the glucosyl bonds were confirmed by coupling constants of the anomeric protons of hydrogen spectrum asβconfiguration.2. Salidroside and its analogues may protect cultured PC12 cells against hypoglycemia and serum limitation-induced injury.3. Microplate quantification has the advantages of less reagents used, high throughput, as well as simultaneous multi-sample analysis. The synthesis compounds all have the efficiency of scavenging DPPH ? radical. |
PDF Full Text Request