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Charles Brenner - One of the best experts on this subject based on the ideXlab platform.

  • Di-, tri- and tetra-5'-O-phosphorothioadenosyl substituted Polyols as inhibitors of Fhit: Importance of the α-β bridging oxygen and β phosphorus replacement
    BMC Chemical Biology, 2001
    Co-Authors: James M Varnum, Wojciech J. Stec, Janina Baraniak, Renata Kaczmarek, Charles Brenner
    Abstract:

    Background The human FHIT gene is inactivated early in the development of many human cancers and loss of Fhit in mouse predisposes to cancer while reintroduction of FHIT suppresses tumor formation via induction of apoptosis. Fhit protein, a diadenosine polyphosphate hydrolase, does not require hydrolase activity to function in tumor suppression and may signal for apoptosis as an enzyme-substrate complex. Thus, high affinity nonhydrolyzable substrate analogs may either promote or antagonize Fhit function, depending on their features, in Fhit + cells. Previously synthesized analogs with phosphorothioadenosyl substitutions and "supercharged" branches do not bind better than natural substrates and thus have limited potential as cellular probes. Results Here we link adenosine 5'- O -phosphates and phosphorothioates to short-Chain Polyols to generate a series of substrate analogs. We obtain structure-activity data in the form of in vitro Fhit inhibition for four types of analog substitutions and describe two compounds, inhibitory constants for which are 65 and 75-fold lower than natural substrates. Conclusions The best Fhit inhibitors obtained to date separate two or more 5'- O -phosphoromonothioadenosyl moieties with as many bond lengths as in AppppA, maintain oxygen at the location of the α-β bridging oxygen, and replace carbon for the β phosphorus.

  • Di-, tri- and tetra-5'-O-phosphorothioadenosyl substituted Polyols as inhibitors of Fhit: Importance of the α-β bridging oxygen and β phosphorus replacement
    BMC Chemical Biology, 2001
    Co-Authors: James M Varnum, Wojciech J. Stec, Janina Baraniak, Renata Kaczmarek, Charles Brenner
    Abstract:

    The human FHIT gene is inactivated early in the development of many human cancers and loss of Fhit in mouse predisposes to cancer while reintroduction of FHIT suppresses tumor formation via induction of apoptosis. Fhit protein, a diadenosine polyphosphate hydrolase, does not require hydrolase activity to function in tumor suppression and may signal for apoptosis as an enzyme-substrate complex. Thus, high affinity nonhydrolyzable substrate analogs may either promote or antagonize Fhit function, depending on their features, in Fhit + cells. Previously synthesized analogs with phosphorothioadenosyl substitutions and "supercharged" branches do not bind better than natural substrates and thus have limited potential as cellular probes. Here we link adenosine 5'-O-phosphates and phosphorothioates to short-Chain Polyols to generate a series of substrate analogs. We obtain structure-activity data in the form of in vitro Fhit inhibition for four types of analog substitutions and describe two compounds, inhibitory constants for which are 65 and 75-fold lower than natural substrates. The best Fhit inhibitors obtained to date separate two or more 5'-O-phosphoromonothioadenosyl moieties with as many bond lengths as in AppppA, maintain oxygen at the location of the α-β bridging oxygen, and replace carbon for the β phosphorus.

Sudarat Issarapanacheewin - One of the best experts on this subject based on the ideXlab platform.

  • hydrogen generation by photocatalytic reforming of potential biofuels Polyols cyclic alcohols and saccharides
    Journal of Photochemistry and Photobiology A-chemistry, 2018
    Co-Authors: Julia Kennedy, Hasliza Bahruji, Michael Bowker, Philip Rosser Davies, Emir Bouleghlimat, Sudarat Issarapanacheewin
    Abstract:

    Abstract We have studied hydrogen gas production using photocatalysis from C2-C5 carbon Chain Polyols, cyclic alcohols and mono and di-saccharides using palladium nanoparticles supported on a TiO2 catalyst. For many of the Polyols the hydrogen evolution rate is found to be dictated by the number of hydroxyl groups and available α-hydrogens in the structure. However the rule only applies to Polyols and cyclic alcohols, while the sugar activity is limited by the bulky structure of those molecules. There was also evidence of ring opening in photocatalytic reforming of cyclic alcohols that involved dehydrogenation and decarbonylation of α C C bond.

Michael Bowker - One of the best experts on this subject based on the ideXlab platform.

  • hydrogen generation by photocatalytic reforming of potential biofuels Polyols cyclic alcohols and saccharides
    Journal of Photochemistry and Photobiology A-chemistry, 2018
    Co-Authors: Julia Kennedy, Hasliza Bahruji, Michael Bowker, Philip Rosser Davies, Emir Bouleghlimat, Sudarat Issarapanacheewin
    Abstract:

    Abstract We have studied hydrogen gas production using photocatalysis from C2-C5 carbon Chain Polyols, cyclic alcohols and mono and di-saccharides using palladium nanoparticles supported on a TiO2 catalyst. For many of the Polyols the hydrogen evolution rate is found to be dictated by the number of hydroxyl groups and available α-hydrogens in the structure. However the rule only applies to Polyols and cyclic alcohols, while the sugar activity is limited by the bulky structure of those molecules. There was also evidence of ring opening in photocatalytic reforming of cyclic alcohols that involved dehydrogenation and decarbonylation of α C C bond.

James M Varnum - One of the best experts on this subject based on the ideXlab platform.

  • Di-, tri- and tetra-5'-O-phosphorothioadenosyl substituted Polyols as inhibitors of Fhit: Importance of the α-β bridging oxygen and β phosphorus replacement
    BMC Chemical Biology, 2001
    Co-Authors: James M Varnum, Wojciech J. Stec, Janina Baraniak, Renata Kaczmarek, Charles Brenner
    Abstract:

    Background The human FHIT gene is inactivated early in the development of many human cancers and loss of Fhit in mouse predisposes to cancer while reintroduction of FHIT suppresses tumor formation via induction of apoptosis. Fhit protein, a diadenosine polyphosphate hydrolase, does not require hydrolase activity to function in tumor suppression and may signal for apoptosis as an enzyme-substrate complex. Thus, high affinity nonhydrolyzable substrate analogs may either promote or antagonize Fhit function, depending on their features, in Fhit + cells. Previously synthesized analogs with phosphorothioadenosyl substitutions and "supercharged" branches do not bind better than natural substrates and thus have limited potential as cellular probes. Results Here we link adenosine 5'- O -phosphates and phosphorothioates to short-Chain Polyols to generate a series of substrate analogs. We obtain structure-activity data in the form of in vitro Fhit inhibition for four types of analog substitutions and describe two compounds, inhibitory constants for which are 65 and 75-fold lower than natural substrates. Conclusions The best Fhit inhibitors obtained to date separate two or more 5'- O -phosphoromonothioadenosyl moieties with as many bond lengths as in AppppA, maintain oxygen at the location of the α-β bridging oxygen, and replace carbon for the β phosphorus.

  • Di-, tri- and tetra-5'-O-phosphorothioadenosyl substituted Polyols as inhibitors of Fhit: Importance of the α-β bridging oxygen and β phosphorus replacement
    BMC Chemical Biology, 2001
    Co-Authors: James M Varnum, Wojciech J. Stec, Janina Baraniak, Renata Kaczmarek, Charles Brenner
    Abstract:

    The human FHIT gene is inactivated early in the development of many human cancers and loss of Fhit in mouse predisposes to cancer while reintroduction of FHIT suppresses tumor formation via induction of apoptosis. Fhit protein, a diadenosine polyphosphate hydrolase, does not require hydrolase activity to function in tumor suppression and may signal for apoptosis as an enzyme-substrate complex. Thus, high affinity nonhydrolyzable substrate analogs may either promote or antagonize Fhit function, depending on their features, in Fhit + cells. Previously synthesized analogs with phosphorothioadenosyl substitutions and "supercharged" branches do not bind better than natural substrates and thus have limited potential as cellular probes. Here we link adenosine 5'-O-phosphates and phosphorothioates to short-Chain Polyols to generate a series of substrate analogs. We obtain structure-activity data in the form of in vitro Fhit inhibition for four types of analog substitutions and describe two compounds, inhibitory constants for which are 65 and 75-fold lower than natural substrates. The best Fhit inhibitors obtained to date separate two or more 5'-O-phosphoromonothioadenosyl moieties with as many bond lengths as in AppppA, maintain oxygen at the location of the α-β bridging oxygen, and replace carbon for the β phosphorus.

Julia Kennedy - One of the best experts on this subject based on the ideXlab platform.

  • hydrogen generation by photocatalytic reforming of potential biofuels Polyols cyclic alcohols and saccharides
    Journal of Photochemistry and Photobiology A-chemistry, 2018
    Co-Authors: Julia Kennedy, Hasliza Bahruji, Michael Bowker, Philip Rosser Davies, Emir Bouleghlimat, Sudarat Issarapanacheewin
    Abstract:

    Abstract We have studied hydrogen gas production using photocatalysis from C2-C5 carbon Chain Polyols, cyclic alcohols and mono and di-saccharides using palladium nanoparticles supported on a TiO2 catalyst. For many of the Polyols the hydrogen evolution rate is found to be dictated by the number of hydroxyl groups and available α-hydrogens in the structure. However the rule only applies to Polyols and cyclic alcohols, while the sugar activity is limited by the bulky structure of those molecules. There was also evidence of ring opening in photocatalytic reforming of cyclic alcohols that involved dehydrogenation and decarbonylation of α C C bond.