Novel bile acid conjugates with aryl/alkenyl linker: Synthesis and characterization

Eight potential precursors for the design of bile acid derived receptors viz. 2,6-bis[dimethyl(3α-hydroxy-5β-cholan-24-amidoethyl)ammonio-methyl]naphthalene dibromide (1), 3,3′-bis[dimethyl(3α-hydroxy-5β-cholan-24-amidoethyl)ammoniomethyl]biphenyl dibromide (2), 3,3′-bis[dimethyl(3α,7α,12α-trihydroxy-5β-cholan-24-amidoethyl)ammoniomethyl]biphenyl dibromide (3), 4,4′-bis[dimethyl(3α-hydroxy-5β-cholan-24-amidoethyl)ammoniomethyl]stilbene dibromide (4), 4,4′-bis[dimethyl(3α,7α,12α-trihydroxy-5β-cholan-24-amidoethyl)ammoniomethyl]stilbene dibromide (5), allyl-dimethyl(3α,7α,12α-trihydroxy-5β-cholan-24-amidoethyl)ammonium bromide (6), 1,4′-bis[dimethyl(3α-hydroxy-5β-cholan-24-amidoethyl)ammonio]but-2-ene dibromide (7), 1,4′-bis[dimethyl(3α,7α,12α-trihydroxy-5β-cholan-24-amidoethyl)ammonio]but-2-ene dibromide (8) have been synthesized in moderate to almost quantitative yields, and their structures have been characterized by 1H, 13C, 13C DEPT-135, PFG 1H, 13C HMQC, and PFG 1H, 13C HMBC NMR spectra. Their molecular weights and elemental compositions have been determined by ESI-TOF mass spectrometry and elemental analyses. trans to cis isomerization of stilbene (4, 5) and 2-butenylene (7, 8) derivatives have also been studied.