80781-23-3Relevant academic research and scientific papers
Regiospecific A,B Capping onto β-Cyclodextrin. Characteristic Remote Substituent Effect on 13C NMR Chemical Shift and Specific Taka-amylase Hydrolysis
Tabushi, Iwao,Nabeshima, Tatsuya,Fujita, Kahee,Matsunaga, Atsuo,Imoto, Taiji
, p. 2638 - 2643 (1985)
A,B-regiospecific (97percent A,B and 3percent A,C) capping of β cyclodextrin was first achieved by the use of m-benzenedisulfonyl chloride.The A,B regiochemistry is ascertained by a remarkable effect of a remote substituent of ring A on the high-field 13C NMR chemical shift of ring B.Further support for the A,B structure is obtained by its specific hydrolysis to disubstituted fragmental sugars catalyzed by Taka-amylase.The novel cap was converted to a series of A,B-disubstituted β-cyclodextrins-diiodo, dideoxy, bis(butylsulfenyl), bis(phenylsulfenyl), andbis((p-tert-butylphenyl)sulfenyl).Characteristic remote chemical shifts in 100 MHz 13C NMR were observed for these A,B derivatives, the C6, C4, and C1 shifts of which were extremely useful for the differentiation of an A,B regioisomer from other regioisomers.Noteworthy is the remarkable chemical shift difference thus produced between C6, C4, and C1 on the A ring and C6, C4, and C1 on the B ring, providing an interesting possibility of spectroscopic determination of clockwise and counterclockwise A,B structure.
