6-De-oxy-α-l-talopyran-ose
Acta Crystallographica. Section E, Structure Reports Online
|January 5, 2011
Summary
X-ray crystallography revealed the α-pyran-ose form of C(6)H(12)O(5) in a chair conformation. The crystal structure features a 3D hydrogen-bonded network, with each molecule donating and accepting four hydrogen bonds.
Area of Science:
- Carbohydrate Chemistry
- Crystallography
- Structural Chemistry
Background:
- Understanding the three-dimensional structure of carbohydrates is crucial for elucidating their biological functions.
- The α-pyran-ose form is a common cyclic structure for monosaccharides.
- Hydrogen bonding plays a significant role in stabilizing crystal structures and influencing molecular interactions.
Purpose of the Study:
- To determine the crystal structure of the title compound, C(6)H(12)O(5).
- To elucidate the conformation of the six-membered ring and the hydrogen bonding network.
- To establish the absolute configuration of the compound.
Main Methods:
- X-ray crystallography was employed to analyze the crystal structure.
- The compound was synthesized using l-fucose as a starting material to determine absolute configuration.
Main Results:
- The compound C(6)H(12)O(5) crystallizes in the α-pyran-ose form.
- The six-membered ring adopts a chair conformation.
- A three-dimensional hydrogen-bonded network was observed, with each molecule acting as both a hydrogen bond donor and acceptor for four bonds.
Conclusions:
- The study successfully determined the detailed crystal structure of C(6)H(12)O(5).
- The findings highlight the importance of hydrogen bonding in the molecular assembly of this carbohydrate.
- The established absolute configuration provides essential stereochemical information.
Related Concept Videos
02:44Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
02:04Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
Diols are compounds with two hydroxyl groups. In addition to syn dihydroxylation, diols can also be synthesized through the process of anti dihydroxylation. The process involves treating an alkene with a peroxycarboxylic acid to form an epoxide. Epoxides are highly strained three-membered rings with oxygen and two carbons occupying the corners of an equilateral triangle. This step is followed by ring-opening of the epoxide in the presence of an aqueous acid to give a trans diol.
01:24Other Glycolytic Pathways
The pentose phosphate pathway (PPP) operates in parallel with glycolysis, facilitating the metabolism of both pentoses and glucose. This pathway consists of two distinct phases: the oxidative and non-oxidative phases. While it does not directly generate ATP, the intermediates formed during the process can integrate into glycolysis, contributing to cellular energy metabolism when required.Oxidative Phase: NADPH ProductionThe oxidative phase of the pentose phosphate pathway is primarily...
01:14Alkylation of β-Diester Enolates: Malonic Ester Synthesis
Malonic ester synthesis is a method to obtain α substituted carboxylic acids from ꞵ-diesters such as diethyl malonate and alkyl halides.
01:14Dehydration of Aldols to Enals: Base-Catalyzed Aldol Condensation
This lesson delves into the aldol condensation catalyzed by bases, where aldols undergo dehydration to enals. As shown in Figure 1, the β-hydroxy aldehyde formed in a base-catalyzed aldol addition reaction dehydrates on heating to yield an unsaturated carbonyl product, which is commonly referred to as an enal.
01:20Energy-requiring Steps of Glycolysis
Glucose is the source of nearly all energy used by organisms. The first step of converting glucose into usable energy is called glycolysis. Glycolysis occurs in the cytosol of the cell over two phases: an energy-requiring phase and an energy-releasing phase. Over the first three steps, glucose is converted into different forms and attached to two phosphate groups donated by two ATP molecules, resulting in an unstable sugar. In the next two stages, the unstable sugar splits into two sugar...