Hexoses: Difference between revisions
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<table width='500' align='right' cellpadding='5'><tr><td rowspan='2'> </td><td bgcolor='#eeeeee'><Structure load='open chain glucose.pdb' size='490' frame='true' align='right' caption='' scene='Hexoses/Glucose_fischer/1' /></td></tr><tr><td bgcolor='#eeeeee'><center><scene name='Hexoses/Glucose_fischer/1'> (Initial scene)</scene></center></td></tr></table> | <table width='500' align='right' cellpadding='5'><tr><td rowspan='2'> </td><td bgcolor='#eeeeee'><Structure load='open chain glucose.pdb' size='490' frame='true' align='right' caption='' scene='Hexoses/Glucose_fischer/1' /></td></tr><tr><td bgcolor='#eeeeee'><center><scene name='Hexoses/Glucose_fischer/1'> (Initial scene)</scene></center></td></tr></table> | ||
The figure to the left contains glucose drawn as a Fischer projection structure. When drawing a Fischer projection the most oxidized group, in this case the aldehyde group, is is positioned at the top, all horizontal bonds project to the front of the plane of the screen and all vertical bonds project behind the plane of the screen. The structure shown to the right in the Jmol applet is drawn in this same conformation, but the structure gives the appearance of being 3D. The applet shows the glucose molecule circling back on itself, so that carbon #6, (green) circles around to meet the aldehyde carbon, C#1 (orange). | The figure to the left contains glucose drawn as a Fischer projection structure. When drawing a Fischer projection the most oxidized group, in this case the aldehyde group, is is positioned at the top, all horizontal bonds project to the front of the plane of the screen and all vertical bonds project behind the plane of the screen. The structure shown to the right in the Jmol applet is drawn in this same conformation, but the structure gives the appearance of being 3D. The applet shows the glucose molecule circling back on itself, so that carbon #6, (green) circles around to meet the aldehyde carbon, C#1 (orange). Projecting this 3D structure on to a 2D surface gives the Fischer projection structure. In order to observe that the hydroxyl groups on the chiral carbons overlay on the two structures, rotate the Jmol structure upward so that C#1 moves to the back of the screen. When you do that, you will see that the hydroxyl groups on the chiral carbons are on the same sides of the carbon chain as where they are in the 2D structure. | ||
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== Terms Defined in Wikipedia == | == Terms Defined in Wikipedia == | ||
{{Reflist}} | {{Reflist}} | ||
Revision as of 00:05, 28 October 2011
The objective of this article is to illustrate and visualize the structures and concepts of glucose (aldohexose[1]) and fructose (ketohexose[2]) that are difficult to visualize and illustrate by viewing two dimensional structures in textbooks.
GlucoseGlucose
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The figure to the left contains glucose drawn as a Fischer projection structure. When drawing a Fischer projection the most oxidized group, in this case the aldehyde group, is is positioned at the top, all horizontal bonds project to the front of the plane of the screen and all vertical bonds project behind the plane of the screen. The structure shown to the right in the Jmol applet is drawn in this same conformation, but the structure gives the appearance of being 3D. The applet shows the glucose molecule circling back on itself, so that carbon #6, (green) circles around to meet the aldehyde carbon, C#1 (orange). Projecting this 3D structure on to a 2D surface gives the Fischer projection structure. In order to observe that the hydroxyl groups on the chiral carbons overlay on the two structures, rotate the Jmol structure upward so that C#1 moves to the back of the screen. When you do that, you will see that the hydroxyl groups on the chiral carbons are on the same sides of the carbon chain as where they are in the 2D structure.