Abstract
The first symmetrical bilirubin analog with CO2H groups replaced by SO3H, 8,12-bis-(2-sulfo-ethyl)-3,17-diethyl-2,7,13,18-tetramethyl-(10H,21H,23H,24H)-bilin-1,19-dione, was synthesized from methyl (2,4-dimethyl-5-ethoxycarbonyl-1H-pyrrol-3-yl) acetate in nine steps via the sulfonic acid analog of xanthobilirubic acid (XBR) and isolated as its disodium salt. The sulfonic acid group was introduced at an early stage of the synthesis by reaction of an intermediate, ethyl 4-(2-bromoethyl)-3,5-dimethyl-1H-pyrrole-2-carboxylate, with sodium sulfite. The disodium bilirubin disulfonate exhibits NMR spectroscopic properties rather similar to those of the parent carboxylic acid, mesobilirubin-XIIIα; however, its UV/Vis spectra are blue-shifted and broadened relative to those of the parent compound. Like mesobilirubin, the disulfonate displays a positive exciton chirality circular dichroism spectrum, albeit with weaker Cotton effects, in a buffered aqueous solution (pH = 7.4) containing a 2:1 molar ratio of human serum albumin.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
