A New Preparative Synthesis of 1-D-6-O-(2-Amino-2-Deoxy-D-glycopyranosyl)-chiro-Inositol 1-Phosphate and 1,2-Cyclic Phosphate

Abstract

A convenient preparative synthesis of 1‐D‐6‐O‐(2‐amino‐2‐deoxy‐α‐D‐glycopyranosyl)‐chiro‐inositol 1‐phosphate (III) and ‐1,2‐cyclic phosphate (IV) using D‐chiro‐inositol as starting material is reported. Compound III has been previously found to behave as type P inositolphosphoglycans (the putative second messengers of insulin‐like growth factor I) in organotypic cultures of chicken embryo. The synthesis of III and IV, now reported, considerably improves previous synthesis of III and permits the effective preparation of these substances for biological investigation.

Synthesis of New Hexosaminyl D‐ and L‐chiro‐Inositols Related to Putative Insulin Mediators

“…The methyl ether group of L ‐quebrachitol was cleaved as previously reported9 to give L ‐ chiro ‐inositol. Treatment of L ‐ chiro ‐inositol with the bifunctional protecting agent 1,3‐dichoro‐1,1,3,3‐tetraisopropyldisiloxane (TIPDSCl 2 ) under carefully controlled experimental conditions1c gave a mixture of silylated derivatives that was directly submitted to conventional benzoylation to give compounds 1a (36%), 1b (22%), and 1c (15%). Removal of the silyl protecting group in 1a afforded diol 2 in 90% yield.…”

“…1a,1b,1d,1e There is no general consensus, however, regarding the structure of P‐type chiro ‐inositol‐containing IPGs 4d. Previously, we synthesized a variety of compounds with the structural motifs IV − VIII 1c,1g,1h because we found incidentally that some of them behaved as P‐type IPGs in inducing cellular differentiation in cultures of chicken embryo,4 but there is no solid experimental evidence for the presence of these structural motifs in the family of naturally occurring P‐type IPGs. On the contrary, assuming that chiro ‐inositol‐containing GPIs are biosynthesized by the same pathway as their myo ‐inositol counterparts, it has been reasoned that their chiro ‐inositol moieties would have the 1‐ L configuration 5.…”

Synthesis of galactosaminyl d-chiro-inositols

“…While several differentially protected 8 chiro-inositols have been synthesized, [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] we sought a general strategy for the syntheses of a complete set of penta-O-benzyl-D D-chiro-inositols, each with a different unprotected hydroxyl group for glycosylation. Since chiro-inositol has a C 2 axis of symmetry, the set consists of only three different penta-O-benzyl-chiro-inositols: 8, 9, and 10.…”

A Study on the Influence of the Structure of the Glycosyl Acceptors on the Stereochemistry of the Glycosylation Reactions with 2‐Azido‐2‐Deoxy‐Hexopyranosyl Trichloroacetimidates

“…The stereoselectivity of these glycosylations also seemed to be somehow dependent on the structure of the acceptor. In the case of the D ‐ chiro ‐inositol derivatives, where a series of pseudodisaccharides were required having the α1→1 glycosidic linkage, the reaction of acceptors 5 , 6 and 7 with 2‐azido‐2‐deoxy‐ D ‐glucopyranosyl trichloroacetimidates, afforded anomeric mixtures containing a considerable amount of the β‐anomers 11c,g,h. By contrast, the α1→2 glycosidic linkage in the same D ‐ chiro series and the α1→3 glycosidic linkage in the L ‐ chiro series11i as well as the α1→6 glycosidic linkage in the D ‐ myo series11b,e were formed with fair to good stereoselectivity under similar experimental conditions.…”