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Resolution of Rac‐Bambuterol via Diastereoisomeric Salt Formation with o‐Chloromandelic Acid and Differences in the Enantiomers' Pharmacodynamical Effects in Guinea Pigs and Beagles 下载免费PDF全文
Jie Wu Fei Liu Shanping Wang Hongjun Wang Qing Liu Xinghan Song Junxiao Li Ling Xu Wen Tan 《Chirality》2016,28(4):306-312
In this study an enantioseparation method for rac‐bambuterol (5‐(2‐(tert‐butylamino)‐1‐hydroxyethyl)‐1,3‐phenylene bis(dimethylcarbamate)) via diastereoisomeric salt formation with o‐chloromandelic acid was developed. The enantiomeric excess (ee) values and chemical purities of the desired products were confirmed by high‐performance liquid chromatography (HPLC) using chiral stationary phase and reverse‐phase HPLC analyses, respectively. The ee values and the chemical purities both exceeded 99%. Animal experiments showed that (R)‐bambuterol was a potent inhibitor for histamine‐induced asthma reactions. (S)‐bambuterol was ineffective in relaxing the airways. Both enantiomers increased heart rates in beagles. Therefore, replacing rac‐bambuterol with (R)‐bambuterol could be beneficial for asthma patients. Chirality 28:306–312, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
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Liu Yang Tan Juan Ou Shuangyan Chen Jun Chen Limin 《Journal of physiology and biochemistry》2019,75(3):391-401
Journal of Physiology and Biochemistry - Adipose tissue has long been considered to be involved in tumor progression. However, the adipocyte-secreted molecular determinants that regulate... 相似文献
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Liu Rongpeng Zeng Wenhui Tan Tingting Chen Tao Luo Qin Qu Dawei Tang Yiyun Long Dingpei Xu Hanfu 《Transgenic research》2019,28(5-6):627-636
Transgenic Research - The silkworm Bombyx mori is a valuable insect that synthesizes bulk amounts of fibroin protein in its posterior silk gland (PSG) and weaves these proteins into silk cocoons.... 相似文献
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Genetic dissection of ethanol tolerance in the budding yeast Saccharomyces cerevisiae 总被引:3,自引:0,他引:3 下载免费PDF全文
Uncovering genetic control of variation in ethanol tolerance in natural populations of yeast Saccharomyces cerevisiae is essential for understanding the evolution of fermentation, the dominant lifestyle of the species, and for improving efficiency of selection for strains with high ethanol tolerance, a character of great economic value for the brewing and biofuel industries. To date, as many as 251 genes have been predicted to be involved in influencing this character. Candidacy of these genes was determined from a tested phenotypic effect following gene knockout, from an induced change in gene function under an ethanol stress condition, or by mutagenesis. This article represents the first genomics approach for dissecting genetic variation in ethanol tolerance between two yeast strains with a highly divergent trait phenotype. We developed a simple but reliable experimental protocol for scoring the phenotype and a set of STR/SNP markers evenly covering the whole genome. We created a mapping population comprising 319 segregants from crossing the parental strains. On the basis of the data sets, we find that the tolerance trait has a high heritability and that additive genetic variance dominates genetic variation of the trait. Segregation at five QTL detected has explained approximately 50% of phenotypic variation; in particular, the major QTL mapped on yeast chromosome 9 has accounted for a quarter of the phenotypic variation. We integrated the QTL analysis with the predicted candidacy of ethanol resistance genes and found that only a few of these candidates fall in the QTL regions. 相似文献