Arabinopyranose

The importance of the configuration and conformation of the saporous group cannot be overstressed. This is demonstrated by the correct prediction that /3-L-arabinopyranose tastes sweet because of its similar configuration... 

When Shallenberger and coworkers attempted to explain the sweetness of /8-D-fructopyranose, they intuitively assigned the anomeric 2-hydroxyl group as AH and the oxygen atom of the 2-(hydroxymethyl) substituent as B. This assignment has since been supported by Lindley and Birch. It was shown that 1,5-anhydro-D-mannitol (15, 2-deoxy-D-fructopyranose ) and jS-D-arabinopyranose (22) (in both of which, one of the AH or B units... 

P212121 Z = 4 Dn = 1.540 R = 0.032 for 1,051 neutron intensities at 123 K. This was an experiment similar to that of the partially deuterated / -L-arabinopyranose already described. The results here were also negative. The room-temperature, neutron-diffraction structure of the un-deuterated compound had been determined previously.11... 

Ci3H1809 1,2,3,4-Tetra-O-acetyl-a-D-arabinopyranose (TARABP)318 C13H1809 1,2,3,4-Tetra-0-acetyl-/ -D-arabinopyranose (TACARP01)318 C15H20O12 Methyl 1,2,3,5-tetra-0-acetyl-/ -D-galactofuranuronate... 

Calcium bis(2-amino-2,3,4-trideoxy-L-gZycero-pentarate) (calcium di-L-glutamate), tetrahydrate D-Arabinono-1,4-lactone Calcium L-arabinonate, pentahydrate Strontium L-arabinonate, pentahydrate Barium D-ribose 5-phosphate, pentahydrate 2-Deoxy-D-en/thro-pentose j8-DL-Arabinopyranose... 

CjHjoO, Ca2+ Cl-2 4 H20 a-L-Arabinopyranose calcium chloride, tetrahydrate ALARCA 38 420... 

The variety of control mechanisms of xylanase synthesis is demonstrated by examples of the synthesis of xylanase induced by xylose (38,74,75). To a list of low-molecular weight xylanase inducers one can add 4-thioxylobiose (80,81) and 4-O-p-D-xylopyranosyl-L-arabinopyranose (73,77). 

The formation of 2,3,4-tri-0-acetyl-5-5-ethyl-5-thio-L-arabinose diethyl dithioacetal (67) when a-L-arabinopyranose tetraacetate (57) was treated o) th ethanethiol in the presence of either zinc chloride or boron trichloride was rationalised by the sequence of reactions shown subsequent work (see below) suggests that an orthoester may be inter-... 

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