Notable chenodeoxycholic acid oligomers—synthesis, characterization, and 7α-OR steric hindrance evaluation

Synthesis and Biological Evaluation of Bile Acid Analogues Inhibitory to Clostridium difficile Spore Germination

“…Primary amide 16b was prepared by acylation of the C3 and C7 alcohols of 1b , followed by conversion to the acid chloride and amidation with ammonia gas (Scheme ). Amides 17b and 18b were synthesized through HATU-mediated coupling of 1b with n -butylamine or pyrrolidine, respectively. Similarly, HATU coupling of 1a with 2-amino-2-methyl-propanol afforded 22a (the corresponding UDCA analogue 22b was not prepared).…”

“…41 followed by conversion to the acid chloride and amidation with ammonia gas (Scheme 2). 42 Amides 17b and 18b were synthesized through HATU-mediated coupling of 1b with nbutylamine or pyrrolidine, respectively. Similarly, HATU coupling of 1a with 2-amino-2-methyl-propanol afforded 22a (the corresponding UDCA analogue 22b was not prepared).…”

Macrocyclic bile acids: from molecular recognition to degradable biomaterial building blocks

“…Dias and coworkers used Yamaguchi type couplings to carry out the direct cyclisation of various bile acid derivatives. [74][75][76][77][78][79][80] Starting from monomers, they observed trimerisation in most cases, although the yields were moderate (32-53%), due to the presence of higher cyclic oligomers and presumably linear compounds. Interestingly, it was not always necessary to protect the C7-and C12-positions.…”

“…76 In fact, when the 7a-hydroxyl was protected via esterification, the increased steric hindrance considerably lowered the yield of the trimer. 79 However, when esterification is carried out with the 12a-hydroxyl, yields increased by approximately 20%. Nevertheless, the highest trimer yields are still obtained from lithocholic acid, using DCC-DMAP coupling, since competitive benzoylation typical of Yamaguchi coupling is not possible.…”

基于胆酸的功能性分子的研究进展

“…cyclocholates 和 cholaphanes 两 种 类 型 [13] . Cyclocho-lates是指几个胆酸分子通过酯键首尾相连形成的环 形分子(图 12(a)) [78] , cholaphanes则是指胆酸分子间通 图 13 与F − 形成氢键的环形胆酸分子 [82] 图 14 羟基被修饰为NH 3 + 的环形胆酸分子 [87] 环形分子与F − 形成了氢键 [82] . Pandy等也得到了类似 的可以通过氢键识别黄素和尿嘧啶的环形分子 [83,84] .…”