The racemate and the enantiomers of cytosporone E [3-heptyl-4,5,6-trihydroxyphthalide (1)], a metabolite of the endophytic fungus, CR200 (Cytospora sp.), were synthesized. The key steps were (i) Sharpless asymmetric dihydroxylation of an alkene (8) and (ii) HPLC separation of the enantiomers of tert-butyldimethylsilyl ether (12) on a chiral stationary phase. The racemate and enantiomers of cyto...

We propose a new method of incorporating the additional knowledge of accent, gender, and wide-context dependency information into ASR systems by utilizing the advantages of Bayesian networks. First, we only incorporate pentaphone-context dependency information. After that, accent and gender information are also integrated. In this method, we can easily extend conventional triphone HMMs to cover...

liquiritigenin is a chiral flavonoid present in plant based food, nutraceuticals, and traditional medicines. it is also an important ingredient present in licorice. the purpose of this study is to explore the pharmacological activity of racemic liquiritigenin utilizing several in vitro assays with relevant roles in colon cancer and diabetes. where possible, the pure enantiomers were tested to i...

maintaining dignity and respect is among patients’ most fundamental rights. the importance of patient dignity, the status quo, patients’ needs, and a shortage of survey studies in this area were the underlying incentives for conducting this study. this was a cross-sectional descriptive study in which data were collected through patient dignity inventory (pdi). the questionnaire was completed by...

The antimicrobial activities of the isomers and enantiomers of pinene were evaluated against bacterial and fungal cells. The agar diffusion test showed that only the positive enantiomers of the α- and β-isomers of pinene were active. The minimal inhibitory concentration (MIC) and minimal microbicidal concentration (MMC) of these monoterpenes were also determined, confirming that the positive en...

Antifungal drug ketoconazole causes severe drug-drug interactions by influencing gene expression and catalytic activity of major drug-metabolizing enzyme cytochrome P450 CYP3A4. Ketoconazole is administered in the form of racemic mixture of two cis-enantiomers, i.e. (+)-ketoconazole and (-)-ketoconazole. Many enantiopure drugs were introduced to human pharmacotherapy in last two decades. In the...

Methods for the enantiomeric quantitative determination of 3 chiral pesticides, paclobutrazol, myclobutanil, and uniconazole, and their residues in soil and water are reported. An effective chiral high-performance liquid chromatographic (HPLC)-UV method using an amylose-tris(3,5-dimethylphenylcarbamate; AD) column was developed for resolving the enantiomers and quantitative determination. The e...

We investigated the enzyme kinetic basis for the stereoselective disposition of R- and S-omeprazole (OME) and racemic OME in human liver microsomes. OME is primarily metabolized by the hepatic cytochrome P450 enzyme system (CYP2C19 and 3A4). The metabolism of each enantiomer and pseudoracemic OME was studied using unlabeled and (13)C(7)-labeled enantiomers. The enantiomers inhibited each other'...

Proton pump inhibitors omeprazole and lansoprazole contain chiral sulfur atom and they are administered as a racemate, i.e. equimolar mixture of S- and R-enantiomers. The enantiopure drugs esomeprazole and dexlansoprazole have been developed and introduced to clinical practice due to their improved clinical and therapeutic properties. Since omeprazole and lansoprazole are activators of aryl hyd...

In recent years there has been considerable interest in the synthesis and separation of enantiomers of organic compounds especially because of their importance in the biochemistry and pharmaceutical industry. High-performance liquid Chromatography is a very useful method for the direct separation of enantiomers. However, about 30−40 years ago, commercially available chiral stationary phases wer...