13C NMR spectral assignments of 3α,3′α-bis(arylcarboxy)-5β-cholan-24-oic acid ethane-1,2-diol diesters: new lithocholic acid-based molecular clefts

Abstract

3α,3′α‐Bis(arylcarboxy)‐5β‐cholan‐24‐oic acid ethane‐1,2‐diol diesters (1–3) were synthesized by the reaction of an aroyl chloride (aroyl=2,6‐dichlorobenzoyl, 2‐naphthoyl and 1‐pyrenoyl) with lithocholic acid (3α‐hydroxy‐5β‐cholan‐24‐oic acid) ethane‐1,2‐diol diester. The 13C NMR chemical shift assignments of the formed molecular clefts 1–3, pyrene‐1‐carboxylic acid methyl ester (4) (used as model compound) and 1‐pyrenoyl chloride (5) are based on literature data and 13C DEPT‐135, 1H,13C HMQC and 1H,13C HMBC experiments. The molecular weights of 1–3 were determined by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. Copyright © 1999 John Wiley & Sons, Ltd.

Bile Acids as Building Blocks of Supramolecular Hosts

“…We have synthesized 2,2'-bipyridine-4,4'-dicarboxylates ( 29a - d , Figure 18 ) [ 114 ] of four bile acid methyl esters from 2,2'-bipyridine-4,4'-dicarboxylic acid and corresponding bile acid methyl esters by Yamaguchi [ 52 ] reaction. Distinct from our other synthesized bile acid-based dimers [ 84 , 85 , 97 , 98 , 99 ], the most favoured conformation of 29a , obtained from the semi-empirical PM3 calculations, is open (∫-type) structure. Most probably this is caused by the lack of aromatic rings in the heads of the dimer which would stabilize the cleft-type conformation.…”

“…We have synthesized lithocholic acid-based molecular clefts and investigated their conformational preferences and Ag + -cation binding properties both experimentally by NMR measurements and theoretically by MO calculations [ 84 , 85 , 97 , 98 , 99 ]. The structures and yields of these open dimers 22a-i , 23a-c are presented in Figure 12 .…”

“…MALDI-TOF is another broadly used technique in the determination of molecular masses of the bile acid derivatives. It has been used in the determination of molecular masses of lithocholic acid-piperazine diamide and lithocholic acid ethane-1,2-diol diester and their derivatives ( Scheme 4 and Figure 12 ) [ 85 , 97 , 98 , 99 ], bile acid-based chiral dendrons ( Figure 17 ) [ 112 ], 2,2'-bipyridine-4,4'-dicarboxylates of bile acid methyl esters ( 29a - d , Figure 20 ) [ 114 ], and bile acid-based polymers [ 116 ].…”

3α,3′α-Bis(n-acetoxyphenylcarboxy)-5β-cholan-24-oic acid ethane-1,2-diol diesters (n = 2-4):13C NMR chemical shifts, variable-temperature and NOE1H NMR measurements and MO calculations of novel bile acid-based dimers

“…8,9 We report syntheses, 13 C NMR spectral assignments, variable-temperature 1 H NMR spectroscopic data and 2D 1 H, 1 H NOESY and PM3 molecular orbital studies of three novel dimers having an ethane-1,2-diol joint, lithocholic acid-based fingers and isomeric acetoxybenzoic acid (2-acetoxy in 1, 3-acetoxy in 2 and 4-acetoxy in 3)-derived finger tips. 8,9 We report syntheses, 13 C NMR spectral assignments, variable-temperature 1 H NMR spectroscopic data and 2D 1 H, 1 H NOESY and PM3 molecular orbital studies of three novel dimers having an ethane-1,2-diol joint, lithocholic acid-based fingers and isomeric acetoxybenzoic acid (2-acetoxy in 1, 3-acetoxy in 2 and 4-acetoxy in 3)-derived finger tips.…”

Bile Acid-Piperazine Diamides: Novel Steroidal Templates in Syntheses of Supramolecular Hosts: Isomeric Pyridine-n-carboxy Containing Dimers and a Cholaphane

“…10 One example of the bile acid based cleft type structures is a host molecule which Kohmoto et al have synthesized from 3a-aminocholanoate derivative and naphthalene-1,4,5,8-tetracarboxylic acid dianhydride. 11 We have also prepared some molecular clefts 12,13 and investigated their Ag + -cation binding properties. 13 In this study we have chosen piperazine as a bridging group for our lithocholic acid derivatives because piperazine has metal complexing capabilities and it is a good hydrogen-bond acceptor, which makes its derivatives interesting for supramolecular complexation chemistry.…”