✍ Scribed by Stéphane Caron; Andrew I. McDonald; Clayton H. Heathcock
No coin nor oath required. For personal study only.
In our effort towards the preparation of squalene synthase inhibitor zaragozic acid A (squalestatin S l, 1) [1-3], we have employed ketone 2, a 1,6-anhydropyranose [4]. As our need for larger quantities of ketone 2 increased, we realized that we needed an improved synthesis of this compound. Although the overall yield from /3-D-galactose pentaacetate (4) was acceptable (30%), the number of steps was large and the synthesis required the use of air-sensitive reagents such as sodium hydride, LiAIH 4 and AICI 3 on rather large scale. We report herein an improved procedure for the preparation of ketone 2.
In his study of the dehydration of the hexoses, Angyal showed that the 1,6anhydrofuranoses were formed as the major product [5]. Since the 1,6-anhydropyranose Corresponding author.
📜 SIMILAR VOLUMES
1,2-Anhydro sugar derivatives are important intermediates for the synthesis of oligosaccharides' and polysaccharides2, and also for chemical modification of monosaccharides3. The synthesis of I,2-anhydro-o-manno-4, -o-gluco-5, and -D-galactopyranose6 derivatives by an intramolecular S,2 reaction of
The synthesis of the isomeric 1,6-anhydro-3-0-benzyl-2-deoxy-2,4-di-Cmethyl-P-D-hexopyranoses and their spectral characterisation are described. 1,6-Anhydro-3-O-benzyl-2-deoxy-4-O-mesyl-2,4-di-C-methyl-~-D-galactopyranose undergoes ring-contraction on solvolysis.