title: Hantupeptins B and C, cytotoxic cyclodepsipeptides from the marine cyanobacterium Lyngbya majuscula

authors: Tripathi, Ashootosh

subjects: Lyngbya majuscule

abstract: Hantupeptins B (2) and C (3) were isolated, along with the previously reported hantupeptin A (1), from the marine cyanobacterium, Lyngbya majuscula, collected from Pulau Hantu Besar, Singapore. Their structures were elucidated by interpretation of extensive 1D and 2D NMR spectroscopic data. Compounds 2 and 3 are cyclic depsipeptides consisting of five α-amino/hydroxy acid residues, including phenyllactic acid, proline, N-methyl-valine, valine, N-methyl-isoleucine, and a β-hydroxy acid unit with different degrees of unsaturation at the terminal end of each molecule. The absolute configurations of the common amino acids and phenyllactic acid were determined by the advanced Marfey’s and chiral HPLC analyses, respectively. The complete stereochemistry of 3-hydroxy-2-methyl-7-octynoic acid moiety in hantupeptin A was elucidated by a combination of homonuclear J-resolved 2D NMR experiments and by Mosher’s method. Hantupeptins B and C showed moderate in vitro cytotoxicity when tested against MOLT-4 (leukemic) and MCF-7 (breast cancer) cell lines.

text: Hantupeptins B and C, cytotoxic cyclodepsipeptides from the marine cyanobacterium Lyngbya majuscula Hantupeptins B (2) and C (3) were isolated, along with the previously reported hantupeptin A (1), from the marine cyanobacterium, Lyngbya majuscula, collected from Pulau Hantu Besar, Singapore. Their structures were elucidated by interpretation of extensive 1D and 2D NMR spectroscopic data. Compounds 2 and 3 are cyclic depsipeptides consisting of five α-amino/hydroxy acid residues, including phenyllactic acid, proline, N-methyl-valine, valine, N-methyl-isoleucine, and a β-hydroxy acid unit with different degrees of unsaturation at the terminal end of each molecule. The absolute configurations of the common amino acids and phenyllactic acid were determined by the advanced Marfey’s and chiral HPLC analyses, respectively. The complete stereochemistry of 3-hydroxy-2-methyl-7-octynoic acid moiety in hantupeptin A was elucidated by a combination of homonuclear J-resolved 2D NMR experiments and by Mosher’s method. Hantupeptins B and C showed moderate in vitro cytotoxicity when tested against MOLT-4 (leukemic) and MCF-7 (breast cancer) cell lines.

year: 2010-02

title: A Bakhtinian homecoming: Potentials and pitfalls for dialogic pedagogy in a contemporary world

authors: White, Elizabeth Jayne

subjects: Bakhtin

abstract: Bakhtin allows us to approach acts as the embryo or seeds of becoming – as existential -  rather than the products of objectified being based on valued knowledge- in doing so he provides a rich research landscape for investigating metaphoricity.

text: A Bakhtinian homecoming: Potentials and pitfalls for dialogic pedagogy in a contemporary world Bakhtin allows us to approach acts as the embryo or seeds of becoming – as existential -  rather than the products of objectified being based on valued knowledge- in doing so he provides a rich research landscape for investigating metaphoricity.

year: 2011

title: Keynote address: Dr. Catherine Love

authors: Love, Catherine

subjects: Maori

abstract: This keynote address for the National Māori Graduates of Psychology Symposium 2002 addresses the history and current state of psychology in New Zealand, with particular attention to issues affecting Maori.

text: Keynote address: Dr. Catherine Love This keynote address for the National Māori Graduates of Psychology Symposium 2002 addresses the history and current state of psychology in New Zealand, with particular attention to issues affecting Maori.

year: 2003