191488-25-2Relevant academic research and scientific papers
Simple and Efficient Routes to Optically Active chiro- and allo-Inositol Derivatives from myo-Inositol
Sureshan, Kana M.,Watanabe, Yutaka
, p. 493 - 496 (2004)
Efficient routes for the gram scale syntheses of optically active chiro- and allo-inositol derivatives from readily available 1,2:4,5-di-O- isopropylidene-myo-inositol (1) are described. Both D and L forms of these isomeric inositols could be synthesized from enantiomers of 1. One-pot methodology for the simultaneous synthesis of both chiro and allo has also been developed. The possible selectivity for the cleavage of trans-ketal in presence of the cis is an added advantage for the syntheses of a variety of protected derivatives for phosphoinositol syntheses. These routes provide synthetically flexible 1,2:4,5-di-O-isopropylidene-chiro-inositol and 1,6:3,4-di-O- isopropylidene-allo-inositol which are difficult to achieve otherwise.
Efficient syntheses of optically pure chiro- and allo-inositol derivatives, azidocyclitols and aminocyclitols from myo-inositol
Sureshan, Kana M.,Ikeda, Kyoko,Asano, Naoki,Watanabe, Yutaka
, p. 4072 - 4080 (2008/09/20)
Efficient routes for the syntheses of optically pure and hitherto unknown l-chiro- and d-allo-inositol derivatives, azido- and aminocyclitols of l-chiro-configuration, diazido- and diaminocyclitols of d-allo-configuration from economically viable myo-inositol are described. These routes provide access to synthetically flexible 1,2:4,5-di-O-isopropylidene-chiro-inositol and 1,6:3,4-di-O-isopropylidene-allo-inositol, which are otherwise difficult to synthesize directly from their parent inositols. A one pot methodology that allows rapid access to both chiro- and allo-inositol derivatives has also been developed. Investigations on the glycosidase inhibitory properties of these novel azido- and amino-inositols unraveled the potentials of these classes of compounds as novel class of glycosidase inhibitors. Both d and l forms of these cyclitols could be synthesized from myo-inositol in gram scales and hence by exploiting the difference in reactivities of cis- and trans-ketals, a variety of protected derivatives, which are useful for the synthesis of unnatural phosphoinositols and natural products, can be synthesized.
Resolution of synthetically useful myo-inositol derivatives using the chiral auxiliary O-acetylmandelic acid
Sureshan, Kana M.,Kiyosawa, Yoko,Han, Fushe,Hyodo, Sayuri,Uno, Yuhki,Watanabe, Yutaka
, p. 231 - 241 (2007/10/03)
Efficient methods for the resolution of various myo-inositol derivatives have been developed using O-acetylmandelic acid (OAM) as the chiral auxiliary. Various methods of introduction of the chiral auxiliary have been compared. DCC mediated coupling betwe
A simple and practical resolution of 1,2:4,5-di-O-isopropylidene-myo-inositol
Sureshan, Kana M.,Yamasaki, Toru,Hayashi, Minoru,Watanabe, Yutaka
, p. 1771 - 1774 (2007/10/03)
An efficient method for the resolution of 1,2:4,5-di-O-isopropylidene-myo-inositol has been developed. The diketal was converted to diastereomeric 3,6-di-O-mandelates by the reaction with (S)-O-acetylmandeloyl chloride. Both the diastereomers could be separated by sequential crystallization in multi-gram quantities. The enantiomers of the diol were obtained by removal of the chiral auxiliaries. Also the trans-isopropylidene was cleaved efficiently to obtain another pair of chiral diols.
Synthesis of the enantiomers of myo-inositol 1,2,4,5-tetrakisphosphate, a regioisomer of myo-inositol 1,3,4,5-tetrakisphosphate
Mills, Stephen J.,Potter, Barry V. L.
, p. 1279 - 1286 (2007/10/03)
Routes for the synthesis of racemic myo-inositol 1,2,4,5-tetrakisphosphate DL-Ins(1,2,4,5)P4 5ab and the chiral antipodes D- and L-myo-inositol 1,2,4,5-tetrakisphosphate 5a and 5b, respectively, are described. For the synthesis of racemate 5ab, 3,6-di-O-benzoyl-1,2:4,5-di-O-isopropylidene-myo-inositol 7ab is prepared in two steps from myo-inositol. The ketals are hydrolysed under acidic conditions to give DL-1,4-di-O-benzoyl-myo-inositol 8ab. Phosphitylation of compounds 8ab using chloro(diethoxy)-phosphine in the presence of base, followed by oxidation and a three-step deprotection strategy, gives DL-Ins(1,2,4,5)P4 5ab. The chiral tetrakisphosphates 5a and 5b are synthesized using a different route. The 4,5-isopropylidene group of DL-3,6-di-O-benzyl-1,2:4,5-di-O-isopropylidene-myo-inositol 13ab are selectively removed under mild acidic conditions to give diol 14ab. p-Methoxybenzylation at the 4,5-positions followed by acid hydrolysis of the cis-isopropylidene ketal affords cis-diol 16ab. Selective coupling of (S)-(+)-O-acetylmandelic acid with diol 16ab at the equatorial hydroxy group provides two diastereoisomers 18 and 19, which are separated by chromatography. Basic hydrolysis of the individual diastereoisomers provides the enantiomers 16a and 16b. Acidic hydrolysis gives D- and L-3,6-di-O-benzyl-myo-inositol 20a and 20b, respectively. Phosphitylation and oxidation of tetraols 20a and 20b gives the fully blocked derivatives, which are deprotected to give tetrakisphosphates 5a and 5b, respectively. The absolute configuration of compound 20a is established by a chemical method. DL-1,2:4,5-Di-O-isopropylidene-myo-inositol 12ab is coupled to (S)-(+)-O-acetylmandelic acid to give a mixture of bis-esters 26 and 27 and crystallisation of the mixture of diastereoisomers affords pure isomer 27. Basic hydrolysis gives the pure enantiomer 12a (for which the absolute configuration is known) and benzylation followed by acid hydrolysis gives tetraol 20a with the same physical properties as compound 20a prepared by a different route described previously. D-Ins(1,2,4,5)P4 5a is a potent mobiliser of intracellular Ca2+ ions in permeabilised platelets, while L-Ins(1,2,4,5)P4 5b is inactive.
