196859-37-7Relevant academic research and scientific papers
Xylopyranoside-based agonists of D-myo-inositol 1,4,5-trisphosphate receptors: Synthesis and effect of stereochemistry on biological activity
Rosenberg, Heidi J.,Riley, Andrew M.,Marwood, Rachel D.,Correa, Vanessa,Taylor, Colin W.,Potter, Barry V.L.
, p. 53 - 66 (2007/10/03)
The synthesis of a series of tetrahydrofuranyl α- and β-xylopyranoside trisphosphates, designed by excision of three motifs of adenophostin A is reported. The synthetic route features improved preparations of allyl α-D-xylopyranoside and its 2-O-benzyl ether, and gives access to four diastereoisomeric trisphosphates, which show a range of abilities to mobilise Ca2+ from the intracellular stores of hepatocytes. A comparison of the potencies of the four trisphosphates provides useful information relating to the effects of stereochemical variation on the recognition of carbohydrate-based trisphosphates by D-myo-inositol 1,4,5-trisphosphate receptors. 1-O-[(3′S,4′R)-3-hydroxytetrahydrofuran-4-yl] α-D-xylopyranoside 3,4,3′-trisphosphate (8) is the most active member of the series with a potency close to Ins(1,4,5)P3; a β-linked analogue, 1-O-[(3′R,4′S)-3-hydroxytetrahydrofuran-4-yl] β-D-xylopyranoside 3,4,3′-trisphosphate, is ca. 20-fold weaker than Ins(1,4,5)P3, and the other compounds are much less active. While no compound attained a potency close to that of adenophostin A, we believe that 8 represents the minimal structure for potent Ca2+-releasing activity in this type of carbohydrate-based analogue.
Molecular dynamics-based models explain the unexpected diastereoselectivity of the sharpless asymmetric dihydroxylation of allyl D- xylosides
Moitessier, Nicolas,Maigret, Bernard,Chretien, Francoise,Chapleur, Yves
, p. 995 - 1005 (2007/10/03)
The catalytic asymmetric dihydroxylation of several allyl 2-O-benzyl-α- D-xylosides with AD-mix β and PYR(DHQD)2 shows almost no diastereofacial selectivity if the 3- and 4-OH groups are unprotected or acetylated. Acetal, benzyl ethers and benzoyl esters enhance the diastereoselectivity, in the opposite sense to that predicted by the 'AD mnemonic', which is completely lost using AD-mix α. In an attempt to understand this behaviour, computational studies of the asymmetric dihydroxylation (AD) of olefins using Sharpless' and Corey's catalysts have been carried out using molecular dynamics. A three-step algorithm was developed taking advantage of the enzyme-like behaviour of catalyst-olefin systems and applied using an ESFF force field. To validate our approach, the first sampling step procedure was then refined and performed using a modified CVFF force field. This led to a U-shaped model in good agreement with that proposed by Corey for the AD of allyl 4-methoxybenzoates, which brings to the fore a role for the methoxy group. This model also accounts for the observed enantioselectivity of styrene dihydroxylation. When applied to the AD of allyl xylosides using AD- mix β, our model accounts well for the observed diastereoselectivity. Both synthetic and modelling results confirmed that aromatic groups on the olefin could be involved in π-π stacking interactions with the aromatic rings of the catalyst and should be important, if not a prerequisite, to achieve high enantio- and diastereoselectivity.
Total synthesis, from D-xylose, of chiral, ring-contracted 1D-myo-inositol 1,4,5-trisphosphate and 1,3,4,5-tetrakisphosphate analogues with C-2 excised
Jenkins, David J.,Potter, Barry V. L.
, p. 41 - 50 (2007/10/03)
A route to chiral, cyclopentane-based congeners of the second messenger 1D-myo-inositol 1,4,5-trisphosphate and its enigmatic metabolite 1D-myo-inositol 1,3,4,5-tetrakisphosphate, starting from D-xylose, is described.Reaction of allyl α-D-xylopyranoside 7 with 2,2,3,3-tetramethoxybutane gave a 1:1 mixture of the 2,3- and 3,4-butanediacetal-protected derivatives 8 and 9.The latter was converted in four steps into 2-O-benzyl-3,4-bis-O-(p-methoxybenzyl)-D-xylopyranose 15, which on reduction with sodium borohydride gave 2-O-benzyl-3,4-bis-O-(p-methoxybenzyl)-D-xylitol 16.Swern oxidation followed by samarium(II) iodide-mediated pinacol coupling gave a 1:3 mixture of 1L-1,2,3,4/5-1-benzyloxy-2,3-dihydroxy-4,5-bis-(p-methoxybenzyloxy)cyclopentane 18 and 1L-1,2,4/3,5-3-benzyloxy-1,2-dihydroxy-4,5-bis-(p-methoxybenzyloxy)cyclopentane 19.The identity of the latter was confirmed by conversion into known compounds, and further elaboration gave the target compounds, 1D-1,2,4/3,5-cyclopentanepentaol 1,3,4-trisphosphate 5 and 1D-1,2,4/3,5-cyclopentanepentaol-1,2,3,4-tetrakisphosphate 6.
