142 research outputs found
2-Deoxy-2,3-O-isopropylidene-2,4-di-C-methyl-β-l-arabinose
X-ray crystallography unequivocally confirmed the stereochemistry of the C atom at position 2 in the carbon scaffold of the title molecule, C10H18O4. The pyranose ring exists in a chair conformation with the methyl group on the C atom in the 2 position in an equatorial configuration. The absolute stereochemistry was determined from the starting material. The crystal structure consists of O—H⋯O hydrogen-bonded chains of molecules running parallel to the b axis
2,3-O-(S)-Benzylidene-2-C-methyl-d-ribono-1,4-lactone
The crystal structure of the title compound, C13H14O5, establishes (i) the (S) – rather than (R) – configuration at the acetal carbon and (ii) that both the acetal and the lactone form five- rather than six-membered rings; the absolute configuration is determined by the use of 2-C-methyl-d-ribono-1,4-lactone as the starting material. The compound consists of hydrogen-bonded chains of molecules running along the a axis; there are no unusual packing features. Only classical hydrogen bonding has been considered
tert-Butyl 2-deoxy-4,5-O-isopropylidene-d-gluconate
The relative configuration of tert-butyl 2-deoxy-4,5-O-isopropylidene-d-gluconate, C13H24O6, an intermediate in the synthesis of 2-deoxy sugars, was determined by X-ray crystallography, and the crystal structure consists of chains of O—H⋯O hydrogen-bonded molecules running parallel to the a axis. There are two molecules in the asymmetric unit. The absolute configuration was inferred from the use of d-erythronolactone as the starting material
(4S,5R,6R)-Methyl 4-hydroxy-4,5-isopropylidenedioxy-4,5,6,7-tetrahydro-1,2,3-triazolo[1,5-a]pyridine-3-carboxylate. Erratum
Corrigendum to Acta Cryst. (2009), E65, o610–o611
3-O-Benzhydryl-2,5-dideoxy-2,5-imino-2-C-methyl-l-lyxono-1,4-lactone
The title bicyclic lactone, C19H19NO3, is an intermediate in the synthesis of chiral α-methylprolines and branched C-methyl pyrrolidines; the absolute configuration was determined by the use of d-erythronolactone as the starting material. It exhibits no unusual crystal packing features, and each molecule acts as a donor and acceptor for one C—H⋯O hydrogen bond
6-Deoxy-α-l-talopyranose
X-ray crystallography showed that the title compound, C6H12O5, crystallizes in the α-pyranose form with the six-membered ring in a chair conformation. The crystal structure exists as a three-dimensional hydrogen-bonded network of molecules with each molecule acting as a donor and aceptor for four hydrogen bonds. The absolute configuration was determined by the use of l-fucose as starting material
1-Deoxy-d-galactitol (l-fucitol)
1-Deoxy-d-galactitol, C6H14O5, exists in the crystalline form as hydrogen-bonded layers of molecules running parallel to the ac plane, with each molecule acting as a donor and acceptor of five hydrogen bonds
6-Azido-6-deoxy-α-l-galactose (6-azido-l-fucose) monohydrate
Although 6-azido-6-deoxy-l-galactose in aqueous solution is in equilibrium between the open-chain, furanose and pyranose forms, it crystallizes solely as 6-azido-6-deoxy-α-l-galactopyranose monohydrate, C6H11N3O5·H2O, with the six-membered ring adopting a chair conformation. The structure exists as hydrogen-bonded chains, with each molecule acting as a donor and acceptor of five hydrogen bonds. There are no unusual crystal packing features and the absolute configuration was determined from the use of 1-azido-1-deoxy-d-galactitol as the starting material
Moving biochemistry and molecular biology courses online in times of disruption: Recommended practices and resources ‐ a collaboration with the faculty community and ASBMB
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163423/2/bmb21354_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163423/1/bmb21354.pd
Socioeconomic factors affecting access to preferred place of death : a qualitative evidence synthesis
- …