Nakanishi’s method

Nakanishi s method is based on the splitting of CD waves when two chromopho-res on a chiral molecule are close in space (the dibenzoate rule). Such is the case with dibromobenzoates of sugars which have a 1,2 or 1,3 relationship. In the first version of the method, saponins were permethylated, methanolyzed with acid and the liberated OH positions were p-bromobenzoylated (44). As terminal sugars are fully methylated and UV transparent, they need not be considered. Branched sugars (two substitutions at least) 3deld di-or tri-benzoates with exciton-split CD curves. The difference in Ae values of the two extrema of split CD curves is directly related to the respective positions of the benzoates (1, 2 eq-eq = 1, 2 eq-ax = 62 1, 2 ax-ax = 6 1, 3 eq-eq = 0 1, 3 eq-ax = 16). The sensitivity of circular dichroism makes the method suitable for microassays. Typical analyses are performed on a 100 pg scale (nanomolar levels). 

Figure 36 Gymnocin-B 80 and the lowest-energy conformation of its 10,37-bis(TPP-cinnamate) derivative 81 obtained by Monte Carlo/MMFF94s with Spartan 02. Experimental CD (in MeOFI, c —3.0 x 10 6) 419nm (Ae+11), 414 nm (Ae-15) Boltzmann weighted (at 298 K) average CD calculated by De Voe s method 420 nm (Ae +25), 414 nm (Ae -25). Redrawn from K. Tanaka Y. Itagaki M. Satake H. Naoki T. Yasumoto K. Nakanishi N. Berova, J. Am. Chem. Soc. 2005, 127, 9561-9570.

Loro, K. A., Orlan, R., Zhang, R, Usherwood, P. N. R., and Nakanishi, K. (1993). Anal. Biochem. 215, 38-44. Separation of the sticky pqjtides from membrane proteins by HPLC in a normal-phase system. Author s note. We were unable to solubilize either DGK3M or any of the polyamino acids in the solvent systems reported in their work, suggesting their method may not be completely general. 

T. Yamagaki, Y. Ishizuka, S.-I. Kawahara, H. Nakanishi. Analysis of glycosidic linkages in saccharide compounds by post-source decay fragment methods in matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy. Rap. Comm. Mass. Spec. 1999, /1,527-531. 

N. C. Gonnella, K. Nakanishi, V. S. Martin and K. B. Sharpless, General method for determining absolute configurations of acyclic allylic alcohols, J. Amer. Chem. 

Kasai H, Okazaki S, Hanada T, Okada S, Oikawa H, Adschiri T, Arai K, Yase K, Nakanishi H (2000) Preparation of C60 Microcrystals Using High-Temperature and High-Pressure Liquid Crystallization Method. Chem. Lett. 12 1392-1393. 

Chen S M L, Harada N, Nakanishi K 1974 Long range effect in the exciton chirality method. J Am Chem Soc 96 7352-7354... 

Oltz E M, Nakanishi K, Yagen B, Corley D G, Rottinghaus G E, Tempesta M S 1986 CD additivity in trichothecene benzoates application as a microanalytical method for trichothecene characterization. Tetrahedron 42 2615-2624... 

Ishizuka N., Nakanishi K., Hirao K. Preparaion and chromatographic application of macroporous silicate in a capillary. J. Sol-Gel Sci. Technol. 2000 19 371-375 Ismail M.G.M.U., Nakai Z., Somiya S. Microstructure and mechanical properties ofmullite prepared by the sol-gel method. I. Am. Ceram. Soc. 1987 70 C7-C8 Ito T. Selectively absorbing filter films for color Braun tube. Indust. Mater. 1998 46 52-56 Ito T., Sol-Gel products news sol-gel coating for contrast enhancement of color cathode-ray tubes. J. Sol-Gel Sci. Technol. 2000 18 287... 

Methods in Enzymology, vol. XLI, Carbohydrate Metabolism , Part B, and vol. XLII, Carbohydrate Metabolism , Part C, ed. W. A. Wood, Academic Press, New York and London, 1975 Natural Products Chemistry , ed. K. Nakanishi, T. Goto, S. Ito, S. Natori, and S. Nazoe, Kodansha, Tokyo, and Academic Press, New York and London, 1975. 

Rickman BH, Matile S, Nakanishi K et al (1998) A two-step chemical/chiroptical method for determining absolute configurations of a-hydroxy acids. Tetrahedron 54 5041-5064 Buckingham AD, Fischer P (2006) Direct chiral discrimination in NMR spectroscopy. Chem Phys 324 111-116... 

Kaizaki S. Apphcation in Stereochemical Analysis of Synthetic Compounds, Natural Products and Biomolecules. In Berova N, Woody RW, Polavarapu PL, Nakanishi K, editors. Advances in Chiroptical Methods John WHey Sons Ltd. Inc., New York 2012, pp. 449-471. 

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