Computational chemical analysis

In this system, the computational chemical analysis targeted the productivity of superoxide from a keto-enol rearrangement to study chemiluminescence intensity in analytical chemistry. Superoxide is toxic in vivo. The partial charge was therefore related to biologic activities, such as toxicity (rat oral LD50), the efficacy of the steroids as an endermic liniment, and the contraction index of blood vessel by steroids. 

Hanai T. Computational chemical analysis of the sensitivity of phenacylesters and steroids in chemiluminescence detection. Jpn Chem Program Exchange J, 2001 13 123-8. 

Hanai T. Quantitative computational chemical analysis of the sensitivity of chemilulminescence detection. J Liq Chrom Rel Technol. 2002 25 2425-31. 

General computational chemical analysis of liquid chromatographic retention is performed without solvents in the calculation. Generally, mixed solvents with and without pH-controlled ions are present as the eluent components in liquid chromatography. At present, these solvent systems cannot be handled by computational chemical calculations. The measurement of direct interactions, however, reveals the different strengths of molecular interactions between an analyte and the packing material surface. The difference in molecular interaction energy values can be used as a relative retention time. 

T. Hanai, K. Koizumi, T. Kinoshita, R. Arora and F. Ahmed, Prediction of pKa values of phenolic and nitrogen-containing compounds by computational chemical analysis compared to those measured by liquid chromatography,/. Chromatogr., A, 1997, 762, 55-61. 

T. Hanai, R. Miyazaki, A. Koseki and T. Kinoshita, Computational chemical analysis of the retention of acidic drugs on a pentyl-bonded silica gel in reversed-phase liquid chromatography,/. Chramatagr. Set, 2004, 42, 354-360. 

T. Hanai, H. Hatano, N. Nimura and T. Kinoshita, Computational chemical analysis of chiral recognition in liquid chromatography, selectivity of iV-(R)-l-(a-naphthyl)ethylaminocarbonyl-(R or 5 )-valine and N-(5 )-l-(ot-naphthyl)ethylaminocarbonyl-(R or 5 )-valine bonded amino-propyl silica gels. Anal Chim. Acta, 1996, 332, 213-224. 

T. Hanai, Computational chemical analysis of enantiomer separations of derivatized amino acids in reversed-phase liquid chromatography, Internet Electron.]. Mol. Des., 2004, 3, 379-386. 

T. Hanai, log nK Chromatography and computational chemical analysis for drug discovery, Curr. Med. Chem., 2005, 12, 501-525. 

T. Hanai, Y. Inoue, T. Sakai and H. Kumagai, Computational chemical analysis of the highly sensitive detection of bromate in ion chromatography,/. Chem. Inf. Comput. Set, 1998, 38, 885-888. 

The possibility of computational chemical analysis of molecular interactions can be understood from the analysis of simple model compounds. Ion-ion interactions were studied for the combination of an ammonium ion (cation) with an acetate ion (anion) by MM2 calculations. The calculated ion-pair formation energy values are as given in Table 2.3. 

A computational chemical analysis using the MM2 program was applied to analyze the retention mechanism of benzoic acid on the guanidine phases. The methyl-bonded phase was used as the blank phase to measure... 

T. Hanai, Computational chemical analysis of the molecular recognition of graphitic carbon, presented at the 21st International Symposium on Capillary Chromatography and Electrophoresis, Park City, 1999. 

The model chiral phases, iV-(tert-butylaminocarbonyl)-(5 )-valylaminobutane (Phase 1) and (J )-l-(a-naphthyl)ethylaminocarbonyl-glycylaminobutane (Phase 2) are shown in Figure 8.1. Phase 1 was used for the enantioseparation of N-acetylamino acid methylesters and [R]- and (5)-4-nitrobenzoyl amino acids, but Phase 2 could not separate these enantiomers. The enantiomer selectivities of N-(5 )-l-(a-naphthyl)ethylaminocarbonyl-(5)-valylaminobutane (Phase 3), N-(5 )-l-(a-naphthyl)ethylaminocarbonyl-(P)-valylaminobutane (Phase 4), N-[R]-1-(oc-naphthyl)ethylaminocarbonyl-(R)-valylaminobutane (Phase 5), and N-[R)-l- a-naphthyl)ethylaminocarbonyl-(5 )-valylaminobutane (Phase 6), which all have two chiral centers, were examined by computational chemical analysis. The structures of model Phases 3-6 are also shown in Figure 8.1. 

The above results indicate that mimic ion-exchange liquid chromatography is feasible compared to using an immobilized-HSA column. The computational chemical analysis of molecular interactions using the mimic ion exchanger is practical for the rapid screening of drug candidates. 

The analytical method described here can predict the relative sensitivity detected by chemiluminescence reactions using luminol, and computational chemical analysis can help to predict sensitive detection in liquid chromatography. The reaction mechanisms of other compounds under similar conditions should be the same as those described for the above compounds. Further computational chemical study will clarify the reaction mechanisms of chemiluminescence and their sensitivity differences. 

R 54 T. Hanai, Chromatography and Computational Chemical Analysis for Drug Discovery , p. 501... 

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