3 alpha,3 'alpha-bis(n-acetoxyphenylcarboxy)-5 beta-cholan-24-oic acid ethane-1,2-diol diesters (n=2-4): C-13 NMR chemical shifts, variable-temperature and NOE H-1 NMR measurements and MO calculations of novel bile acid-based dimers

摘要

Three novel bile acid-based molecular dimers, 3 alpha,3'alpha-bis(n -acetoxyphenylcarboxy)-5 beta-cholan-24-oic acid ethane-1,2-diol diesters (n = 2-4), 1-3, were synthesized from lithocholic acid (3 alpha-hydroxy-5 beta-cholan-24-oic acid) ethane-1,2-diol diester and isomeric n-acetoxybenzoyl chlorides (n = 2-4). Their cleft-type conformational preferences were suggested theoretically by PM3 molecular orbital calculations. Molecular weights determined by the matrix-assisted laser desorption/ionization time-of-flight technique and C-13 NMR chemical shifts of the 1-3 are also presented. Copyright (C) 2000 John Wiley & Sons, Ltd. [References: 27]