ORGN 205 |
| Bilirubin IXa, the yellow pigment of jaundice, is able to adopt a ridge-tile shape due to the formation of intramolecular hydrogen bonds. The shape of bilirubin IXa causes it to be lipophilic, due to the hydrogen bonds engaging the polar components of bilirubin IXa. When the carboxylic acid groups of bilirubin are converted to esters, the hydrogen bonds are disrupted thereby altering the shape and polarity of the molecule. This fascinating interplay between polarity, shape and hydrogen bonding, led us to design and synthesize simpler models of bilirubin. One-half of bilirubin was prepared with an alkanoic chain attached to position nine (semirubin). The [2]-semirubin series is interesting: its short alkyl chain affects the entire molecule, especially when the ester group is converted to an acid with or without an a-keto group. Various [2]-semirubins are studied by 1H NMR, UV-vis spectroscopy (Beers Law) and VPO measurements. X-ray crystal structures were also obtain for most of the [2]-semirubin series.
|
|
Molecular Recognition and Self-Assembly
8:00 AM-12:00 PM, Monday, 27 March 2006 Georgia World Congress Center -- C302, Oral
Division of Organic Chemistry |