257603-84-2Relevant academic research and scientific papers
Synthesis and conformational investigation of methyl 4a-carba-D-arabinofuranosides
Callam,Lowary
, p. 8961 - 8972 (2007/10/03)
The synthesis of carbasugar analogues of methyl α-D-arabinofuranoside and methyl β-D-arabinofuranoside (3 and 4) is reported. The route developed involves the conversion of D-mannose into a suitably protected diene (13), which is then cyclized via olefin metathesis. The resulting cyclopentene (14) is stereoselectively hydrogenated to provide an intermediate that can be used for the synthesis of both targets. Through the use of NMR spectroscopy, we have probed the ring conformation of 3 and 4, as well as the rotamer populations about the C4-C5 and C1-O1 bonds. These studies have demonstrated that there are differences in ring conformation between these carbasugars and their glycoside parents (1 and 2). However, only minor differences are seen in the rotameric equilibrium about the C4-C5 bond in 3 and 4 relative to 1 and 2. In regard to the C1-O1 bond, NOE data from 3 and 4 suggest that the favored position about this bond is similar to that in the glycosides; that is, the methyl group is anti to C2. However, confirmation of this preference through measurement of 3JC,C between the methyl group and C2 or C4a was not successful.
Total synthesis of both methyl 4a-carba-D-arabinofuranosides.
Callam,Lowary
, p. 167 - 169 (2007/10/03)
[reaction: see text] The total synthesis of methyl 4a-carba-alpha-D-arabinofuranoside (1) and methyl 4a-carba-beta-D-arabinofuranoside (2) has been achieved starting from D-mannose (5). Key transformations included a ring-closing metathesis of diene 11 em
