182075-57-6Relevant articles and documents
Stereo- and regiospecificity of yeast phytases-chemical synthesis and enzymatic conversion of the substrate analogues neo- and L-chiro-inositol hexakisphosphate
Adelt, Stephan,Podeschwa, Michael,Dallmann, Guido,Altenbach, Hans-Josef,Vogel, Guenter
, p. 44 - 67 (2007/10/03)
Phytases are enzymes that catalyze the hydrolysis of phosphate esters in myo-inositol hexakisphosphate (phytic acid). The precise routes of enzymatic dephosphorylation by phytases of the yeast strains Saccharomyces cerevisiae and Pichia rhodanensis have been investigated up to the myo-inositol trisphosphate level, including the absolute configuration of the intermediates. Stereoselective assignment of the myo-inositol pentakisphosphates (D-myo-inositol 1,2,4,5,6-pentakisphosphate and D-myo-inositol 1,2,3,4,5-pentakisphosphate) generated was accomplished by a new method based on enantiospecific enzymatic conversion and HPLC analysis. Via conduritol B or E derivatives the total syntheses of two epimers of myo-inositol hexakisphosphate, neo-inositol hexakisphosphate and L-chiro-inositol hexakisphosphate were performed to examine the specificity of the yeast phytases with these substrate analogues. A comparison of kinetic data and the degradation pathways determined gave the first hints about the molecular recognition of inositol hexakisphosphates by the enzymes. Exploitation of the high stereo- and regiospecificity observed in the dephosphorylation of neo- and L-chiro-inositol hexakisphosphate made it possible to establish enzyme-assisted steps for the synthesis of D-neo-inositol 1,2,5,6-tetrakisphosphate, L-chiro-inositol 1,2,3,5,6-pentakisphosphate and L-chiro-inositol 1,2,3,6-tetrakisphosphate.
Efficient synthesis of enantiopure conduritols by ring-closing metathesis
Jorgensen,Iversen,Paulsen,Madsen
, p. 4630 - 4634 (2007/10/03)
Two short synthetic approaches to enantiopure conduritols are described starting from the chiral pool. In both cases, the cyclohexene ring is assembled via ring-closing olefin metathesis. The terminal diene precursers for the metathesis reaction are prepared either from octitols or from tartaric acids. The former route involves a new method for selective bromination of the primary positions in long-chain carbohydrate polyols. Subsequent reductive elimination with zinc then generates the diene. The latter route uses a highly diastereoselective addition of divinylzinc to tartaric dialdehydes for preparation of the dienes.
Enzymatic desymmetrisation of conduritol D. Preparation of homochiral intermediates for the synthesis of cyclitols and aminocyclitols
Patti, Angela,Sanfilippo, Claudia,Piattelli, Mario,Nicolosi, Giovanni
, p. 2665 - 2670 (2007/10/03)
From meso-conduritol D tetraacetate four homochiral partial derivatives, namely (+)-(1R,2R,3S,4S)-1-hydroxy-2,3,4-triacetoxy-5-cyclohexene, (-)-(1R,2R,3S,4S)-2-hydroxy-1,3,4-triacetoxy-5-cyclohexene, (-)-(1R,2R,3S,4S)-1-benzyloxy-3,4-diacetoxy-2-hydroxy-5-cyclohexene and (+)-(1R,2R,3S,4S)-3,4-diacetoxy-1,2-dihydroxy-5-cyclohexene, have been prepared through enzymatic reactions catalysed by one of the following lipases: from porcine pancreas, from Mucor miehei and from Candida cylindracea. These compounds are of potential utility in the synthesis of cyclitols and aminocyclitols. As an example, the preparation of the previously unreported (+)-conduramine C-4 is also reported.
